Scott Watson
sage
Reged: 05/26/06
Posts: 354
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The "sad state" thread got me to thinking. I agree with one post that said (paraphrasing), that changes come in quantum jumps with periods of relative stability in between. One can point to Galileo, Newton, Maxwell, Einstein etc. Technolology is much the same way. So, my question is, in the next 10 years, what will the likely breakthroughs be?
Personally, I think that materials science is getting to the point where a thin, inexpensive, carbon-fiber-like mirror will be made for the masses. I also expect that deformable mirrors will become available for the average joe. Al Nagler is making me believe that 100 AFOV should be a common thing.
What are your thoughts?
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perfessor
professor emeritus
Reged: 12/30/07
Posts: 513
Loc: Northern Illinois
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My first thought is, anything Al Nagler comes up with is not "ATM". To the point, what can we ATMers do, that the pros cannot? Fifty years ago, it was primaries at a reasonable price. Twenty-five years ago, big mounts. Now that pyrex is becoming a stumbling block, I hopefully agree that new mirror materials and methods will be developed.
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Tom
"Don't always know what I'm talkin about"
8" f/7
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rboe
Reged: 03/16/02
Posts: 47531
Loc: Phx, AZ
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I was thinking just the other day; what if we replaced the secondary mirror on newtonian with a forth generation light tube - the kind they use in night vision devices? Surplus stuff is making it to the market, ATM'ers like to use surplus stuff to either save a buck or do something wild.
So I see some experiments away from the traditional optics to really push the envelope.
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Ron
NS11GPS
Pronto
16" dob
15X70 Obies
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RossSackett
scholastic sledgehammer
Reged: 08/17/07
Posts: 756
Loc: Memphis, TN
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I've been thinking about the engineering consequences of a big-light mirror revolution. Our current generation of big ultralights is designed around a relatively heavy mirror and low center of gravity. Carbon fiber replica mirrors (or something more exotic) would be so light that the c.g. will be closer to the midpoint of the optical tube, and will require a different structure. The traditional way of handling that would be a double truss with an intermediate ring carrying the altitude trunnions. Probabaly this will make the first generation of the new scopes look rather clunky and retro. I wonder where it will go from there?
Ross
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"A craftsman relies on science when the state of knowledge allows it, tradition and experience when it does not, and makes art whenever he can."
12 scopes from 4.25 to 18" and a 24" in progress. 12 ATM awards. Webpage: http://stardazed.com/ Some more scope pix at http://www.flickr.com/photos/8315630@N04/
Anagrams: Amateur astronomer = A mature moon-starer; Dobsonian maker = Debonair as monk
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kfrederick
scholastic sledgehammer
Reged: 02/01/08
Posts: 783
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maybe refractors that melt diferent glass together to have a single fast lens. or maybe ED JONES is doing it now with his CHief reflector.
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Ed Jones
Pooh-Bah
Reged: 04/06/04
Posts: 1477
Loc: Sin-sin-atti
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I think it will be simple a unobstructed scope in the f/6-f/7 range like the one I brought to Stellafane.
Quote:
Quoting Dick Suiter “If ever a simple-to-make TCT could be designed with good field of view and good central correction, I would say they finally have something.”
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Ed Jones
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jayscheuerle
Post Laureate
Reged: 01/16/06
Posts: 4263
Loc: S. Philadelphia, PA
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Tracking/goto for dobs that's simple and cheap. Not the "train & track" JMI version, but with a real map of the sky, like ServoCat.
Ultralight, grab-n-go, travel dobs in the 12" to 20" range that unchain themselves from symmetrical convention in design. - j
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Fight indignorance!
120ED, 12" f/5 Green Goblin, 6" f/5 Eero2, 4.5" f/8 PortaBowl, 8" f/5 Big Red Ed.
The PortaBowl-a $100 4.5" f/8 ball-scope YOU can build!
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Mark Harry
Post Laureate
Reged: 09/05/05
Posts: 3401
Loc: Northeast
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Simpler, cheaper narrow-band solar scopes? Ed, how about posting your design of the Chief in cloudy nights for those who have "difficulty" logging onto Yahoo? I'm terribly interested and curious about it.
Mark
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So many projects, so little time!
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mconnelley
sage
Reged: 03/14/06
Posts: 281
Loc: Fremont, CA
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Hello:
I've also considered the problem of having a big and really light mirror. Such a mirror would also likely be pretty fast. I think the solution is a Nasmyth Cassegrain layout. This way the eyepiece is close to the ground and the tube (such as it is) will be kept short. All the top end will have to do is support the secondary mirror since the eyepeice, focuser, and finder will be down at the bottom. However, the secondary might be as large as 12" for a 1 m scope, so that's not a trivial amount of weight. The longer focal ratio of the Cassegrain and the additional degree of freedom with the cc of the secondary will lead to some interesting combinations and trade-offs.
Regarding the comment on DMs, I think it'll be a while before many amateurs are using them. A few of us work with DMs professionally and are ATMers, and we don't even have them working on our scopes yet! Getting a DM working on an amateur scope in closed loop would take a lot of work, and wouldn't be particularly useful for many of the things amateurs look at.
First: Nearly all AO systems work in the infrared, but we look in visible light, so you'd need to share the few photons your scope is collecting between the wavefront sensor and your eyeball. Most AO systems work on 4+ m telescopes, which gather a lot of light.
Second: You'd need a REALLY stable mount so that you can lock onto the guide star and track it accurately (you won't want to burn DM stroke following tracking errors). Many DMs are mounted on a tip-tilt mount to offload things like tracking errors from the DM to the tip-tilt mount.
Third: You'd need to add a wavefront sensor to your scope, and bring along the power supplies, drive electronics, and computers to run the system. Hopefully your scope can be made to focus and balance with the wavefront sensor.
Fourth: No AO system I know of can use an extended object (i.e. the planets) as a guide source. The only thing that a conventional AO system would work on that amateurs look at are double stars. Given the time, effort, and money, is it worth it just to be able to split double stars? I'm working (here and there) on a wavefront sensor that could use the planets as the "guide star", and according to my calculations (famous last words) it'll work.
Fifth: Many amateurs with scopes in the ~8" and smaller rangs wouldn't see much benefit from an AO system since smaller scopes are often diffraction limited anyway. Bigger scopes, which are always seeing limited, would see the most benefit, and also gather enough light for the wavefront sensor to work. Also, AO works best in good seeing!
Sixth: Even small DMs are quite expensive (>$10K). The detector(s) in the wavefront sensor are also expensive and can be quite fragile. Some wavefront sensors use an ordinary CCD, and we know how much those cost. Others use APDs (up to 188 at a few $K each). There's a new avalanching CCD technology that looks quite promising, but I have no clue how expensive that'll be. Adding the cost of the power supplies, computer, drive electronics, wavefront sensor optics and other hardware, it's easy to see why these things tend to take many engineers and scientists years and millions of $ to build. Mass production for the amateur market would drive the unit cost down, but there's still the fundamental costs of the DM, the detector, and the optics, so I don't see even a relatively basic AO system for amateurs costing less than $20K-$50K any time soon.
Seventh: AO is a technology, which has it's limitations. It can help correct for seeing, but it won't completely correct for it, and it be able to achieve a high level of correction all of the time. Sometimes the seeing it just too bad and too fast for an AO system to keep up with. The users expectations will have to be adjusted accordingly.
None of these points are show stoppers, just things to consider. I hope that some amateurs will get AO working on their scopes some day soon. I suspect that it'll be someone who works on it professionally, who has the know how, and who has access to the expertise and spare parts to cobble something together in their lab.
Cheers
Mike Connelley
who dabbles with AO and DMs at from time to time....
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Luigi
Postmaster
Reged: 07/03/07
Posts: 5272
Loc: MA
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>>>I'm working (here and there) on a wavefront sensor that could use the planets as the "guide star"<<<
Interesting! Would you mind letting us in on the principal? I'm familliar with AO as I've worked a bit on the MCAO project for Gemini South.
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17.5" f/5 Dob. IM-715 MCT. 120ED. Lunt 60mm Ha.
Zeiss, Leica, Fujinon, Nikon, Pentax, Bushnell bins
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amper
journeyman
Reged: 07/18/08
Posts: 7
Loc: FM29LW
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I'm not sure a "revolution" per se is in the offing, but there are developments that I've been reading about that may make for some very interesting evolutionary improvements. One is the continually dropping price of small-scale CAD machines. Another is things like the very interesting recent discussions that have been taking place here, and on the Yahoo! Groups Astrogrpah group, related to Newtonian telescopes with hyperbolic primary mirrors and coma correctors, similar to the design of the Takahashi Epsilon astrograph. I also think that there seems to be an upswing of interest in binocular telescopes.
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Have: 2x Pentax PIF 7x50
Want to build: 8" f/6 hyperbolic Newtonian binocular telescope
Want to buy: Nikon 20x120 Binoscope, Pentax PIF 10x50
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refractory
Pooh-Bah
Reged: 02/05/05
Posts: 1263
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Giant ultrathin gradient index lenses, for those who like big refractors. Paper-thin glass would revolutionize everything in the 100mm plus range- you could get rid of a lot of the weight of tubes, mountings, etc., both for scopes and binoculars. GRIN Cat correctors might also have a place.
Jess Tauber
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GJJim
scholastic sledgehammer
Reged: 09/09/06
Posts: 907
Loc: Western CO
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I see a shift away from viewing at an eyepiece to equipment that presents an "image" at a remote display. The technologies are here now: cooled video cams, fast computers, and software that can do image processing in near real time.
Would it still be amateur astronomy? I don't know.
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Luigi
Postmaster
Reged: 07/03/07
Posts: 5272
Loc: MA
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The equipment to view an image remotely has been around for some time. 50 years ago my dad had slides of images taken by the Palomar telscope and a projector to show them. Anyway, this remote viewing "revolution" is not ATM driven, it's trickle down from professional and other commercial technologies. I don't think paper thin or gradient lenses will come out of the ATM innovation either. Super light wiffled out mirrors and composite mirrors already exist for space and military applications where there's plenty of money to support the development and manufacture of these technologies.
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17.5" f/5 Dob. IM-715 MCT. 120ED. Lunt 60mm Ha.
Zeiss, Leica, Fujinon, Nikon, Pentax, Bushnell bins
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mark cowan
Vendor (Obsidian Optics)
Reged: 06/03/05
Posts: 2316
Loc: salem, OR
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Right, you can make light-weighted single-crystal silicon mirrors today, if you can afford the substrate and want ultimate performance.  Composite mirrors still have fairly closely held specs and the progress seems quite linear so far...
Best,
Mark
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GJJim
scholastic sledgehammer
Reged: 09/09/06
Posts: 907
Loc: Western CO
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Perhaps you missed the point. Viewing the image at a remote display is only part of the puzzle. The other technologies combined allow a modest aperture (10"-16") telescope to produce images that rival those seen in your dad's Mt. Palomar slides -- in near real time. As I see it this could be the death knell for big Dobs and it would obviate the need for large lightweight mirrors, fancy eyepieces that work at f/3.5, and orchard ladders at star parties.
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rwiederrich
Goldfinger
Reged: 11/17/05
Posts: 8681
Loc: Bremerton Washington
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Quote:
Perhaps you missed the point. Viewing the image at a remote display is only part of the puzzle. The other technologies combined allow a modest aperture (10"-16") telescope to produce images that rival those seen in your dad's Mt. Palomar slides -- in near real time. As I see it this could be the death knell for big Dobs and it would obviate the need for large lightweight mirrors, fancy eyepieces that work at f/3.5, and orchard ladders at star parties.
That day is now.. Live video cameras are sweet.
The update, and stack images, and in short order..you have an image that took film guys hours of precise work to accomplish. You don't even need stacking/image control programs any more....just the camera and a TV. Real time Wonders. No big Dobs needed..just a small simple 8" newt on a good GoTo Mount.
Rob
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www.goldmtobservingcenter.com
A great place for amateur astronomers, and ATM's to come and enjoy their hobby.
http://tech.groups.yahoo.com/group/HomemadeRefractorTelescopes/ My homemade refractor group.
www.vimeo.com/6014031
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kfrederick
scholastic sledgehammer
Reged: 02/01/08
Posts: 783
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i think very big fast optics like f 3.5 or maybe yolo/s or big folded refractors
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GJJim
scholastic sledgehammer
Reged: 09/09/06
Posts: 907
Loc: Western CO
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Quote:
That day is now.. Live video cameras are sweet.
The update, and stack images, and in short order..you have an image that took film guys hours of precise work to accomplish. You don't even need stacking/image control programs any more....just the camera and a TV. Real time Wonders. No big Dobs needed..just a small simple 8" newt on a good GoTo Mount.
I disagree about the need for stacking. Current "live" video cams require too much fussing and focusing and for every "wow" moment there seems to be ten minutes of frustration and fuzzy, off center images. What I'm suggesting is a piece of software between the camera and display that automatically focuses, captures, and stacks multiple images and then updates the display so the viewer only sees "wow" moments.
Again, I'm not sure that constitutes amateur astronomy as most of us know (knew?) it, but it sure seems things are heading in that direction.
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jeffg
member
Reged: 02/13/07
Posts: 69
Loc: Irvine CA
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I agree that we're headed to less visual observing and more CCD/video displays. Combined with smart go-to, autofocusing, auto-centering, and real time image processing. There's also no reason to stay in the visual band either, but move into the UV and IR as the atmosphere bandpass allows. 
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Jeff
14", 10", & 4.25" Dobs
and some other stuff
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Lamb0
Carpal Tunnel
Reged: 07/25/07
Posts: 1587
Loc: Fairbury, Nebraska
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 For the time being, I prefer the Mark 1 eyeball to "live" images and grainy image intensifiers. Perhaps it's more evolution, than revolution. Fast, light weight mirrors, perhaps conical, with parabolic correctors with field flatteners and eyepieces optimized for sub f/4 optics, and the engineering changes to accomodate a 24" f/3 for flat footed viewing would be "nice"!
John 
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cnstarz
professor emeritus
Reged: 12/22/07
Posts: 549
Loc: Kentucky, USA
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I've been following the progress of the LSST, which was featured in the Sept 08 S&T issue, and I think that acquiring and improving data mining software will become a big part of Amature Astronomy's future. That said visual Astronomy will always be an impressive introduction for most people to our hobby but for those who want to go deeper and further information technology will be the ultimate choice.
I know that sounds boring but just like people put together file sharing applications I imagine a person can download a few applications that will allow them to make custom querys of the data these systems gather to produce amazing discoverys.
For example the Galaxy Zoo DiscoveryHanny's Object In the middle of the thread someone launches a query looking for similar blobs in the data... Very interesting.
IMHO
Edited by cnstarz (08/08/08 04:43 AM)
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jayscheuerle
Post Laureate
Reged: 01/16/06
Posts: 4263
Loc: S. Philadelphia, PA
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I thought this question was about ATMing, not revolutions in general astronomy.
? - j
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Fight indignorance!
120ED, 12" f/5 Green Goblin, 6" f/5 Eero2, 4.5" f/8 PortaBowl, 8" f/5 Big Red Ed.
The PortaBowl-a $100 4.5" f/8 ball-scope YOU can build!
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RossSackett
scholastic sledgehammer
Reged: 08/17/07
Posts: 756
Loc: Memphis, TN
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Quote:
I agree that we're headed to less visual observing and more CCD/video displays. Combined with smart go-to, autofocusing, auto-centering, and real time image processing
I certainly hope not: it would give skywatching all the slug-like passive appeal of watching TV. But I think you are right--that course would appeal to a lot of people. It would also expand the market for high-end accessories, and thus become prominent in ads in the astro-mags, which have always had a big impact on the direction of our hobby.
I'll take the mosquitos, dewing, and star-hopping, thank you, and remain a militant visual observer.
Ross
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"A craftsman relies on science when the state of knowledge allows it, tradition and experience when it does not, and makes art whenever he can."
12 scopes from 4.25 to 18" and a 24" in progress. 12 ATM awards. Webpage: http://stardazed.com/ Some more scope pix at http://www.flickr.com/photos/8315630@N04/
Anagrams: Amateur astronomer = A mature moon-starer; Dobsonian maker = Debonair as monk
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tim53
Carpal Tunnel
Reged: 12/17/04
Posts: 2318
Loc: Highland Park, CA
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Mike beat me to it:
Very large aperture Cassegrain and Nazmith dobsonians. Size limit would likely be the vehicle used to transport it.
Spin cast mirrors for the amatuer?
Video-based systems with a small machine vision 16-bit digital camera (not an analog video camera) in place of the secondary. (some of these can already take "video" at frame rates between 200fps to 1fph).
-Tim.
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"In the old days, before the discovery of eruptions, the lava had to be carried by hand down the mountain and thrown on the sleeping villagers. This took a lot of time." - New Yorker Cartoon, ~ 1980
Hatch Observatory details:
http://www.cloudynights.com/ubbthreads/showflat.php?Cat=0&Number=3593949&page=0&view=collapsed&sb=5&o=all&fpart=1&vc=&PHPSESSID=
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Houdini
professor emeritus
Reged: 07/13/07
Posts: 579
Loc: Europe
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Quote:
Size limit would likely be the vehicle used to transport it.
Isn't that the case already ?
Robert
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16" f/4.9 motorized alt-az, 25" f/5 Dobson, 43" f/4 alt-az under construction
Mirror Edge Support Calculator
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Mike I. Jones
Carpal Tunnel
Reged: 07/02/06
Posts: 1671
Loc: Fort Worth TX
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Along the lines of Ed's window scopes, I think a re-emergence of the "camera lucida" with modern well-corrected optics and computerized pointing and tracking would be fun. The idea of comfortable, high-resolution viewing at room temperature while the optics get to freeze, or swelter in a swarm of mosquitoes, and I get to sit in my skivvies with a Corona in hand and Radian, Panoptic or Ethos at my eye, is most appealing.
A good use of the lightweight glass or low-CTE CF mirrors discussed above would be steering flats for indoor scopes. The only optics out in the weather would be a precision BK7 environmental window, and either one or two enclosed optical flats in a heliostat, coelostat or Coude arrangement with pointing and tracking capability. What comes into the house or observatory are simply plane waves, arriving from any chosen direction in the sky, and tracked to arc-second accuracy. One could then place any telescope at the indoor port, limited only by the aperture of the window and flat(s). The indoor telescope would of course remain stationary, as the external mirrors are doing the tracking. Digital imaging would also benefit from an external pointer/tracker system and indoor scope and CCD or DSLR.
If you want low-power RFT viewing, install a short focus ED or apo refractor. If you want high-power planetary viewing, mount a Cassegrain, Mak, Houghton Cass, SCT, whatever at the port.
The only drawback to this is that the flats would have to be larger than the telescope clear aperture. So, the next evolution, if not revolution, in ATM's could be ATM-built ring polishers for making large flats, and flat-testing equipment.
Mike
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56 mirrors, lenses, 16" f/6 Newt, 6" f/10 refractor, TOA-130S, Tinsley 5" f/15 Mak, 6" f/4 RFT, Coronado PST. Still to build: 24" f/10 Modified Dall-Kirkham, 10" f/26 Mak, 8" f/12 apo, spectrohelioscope, Herrig, Schupmann, and others.
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jeffg
member
Reged: 02/13/07
Posts: 69
Loc: Irvine CA
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Ross:
Don't get me wrong, I love looking through the eyepiece under a really dark sky. It's just that looking through any astro magazine, it's the tech gadgets that get everyone drooling.
I've sort of settled on a compromise. Once a month I head to the desert to use my 14" Dob. The rest of the time I settle for go-to and a CCD under my very light polluted skies at home. 
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Jeff
14", 10", & 4.25" Dobs
and some other stuff
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cnstarz
professor emeritus
Reged: 12/22/07
Posts: 549
Loc: Kentucky, USA
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Quote:
I thought this question was about ATMing, not revolutions in general astronomy.
? - j
I dont see the two as mutually exclusive, where general astronomy goes so goes ATMing.
The way I see it the data represents the sky, the software represents the telescope. I realise it's more of a stretch than the OP was looking for 
Cheers,
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Matt
Apogee 50mm BB scope
ETX-60 BB
Meade 70-az
5" DIY Newt (wip)
C6-N on CG-4 GEM
Gallery
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Michael Miles
professor emeritus
Reged: 02/11/05
Posts: 677
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Quote:
I dont see the two as mutually exclusive, where general astronomy goes so goes ATMing.
The way I see it the data represents the sky, the software represents the telescope. I realise it's more of a stretch than the OP was looking for
Cheers,
I like it when the innovation goes the other direction. Recently, a friend sent me a web link telling about professional astronomers using highspeed sensors to capture short moments of excellent seeing on large telescopes. I enjoyed telling him that amatuer astronomers have been doing this for years with web cams and getting fantastic planetary results.
So, here's where I'll make my pitch for ATM future shock. I think we're really heading toward realtime video astronomy. I currently have a 15" 720p monitor that runs on 12v, and I'm planning on using it with my Canon Digital Rebel. I've tried it under my roof, with a previously exposed frame, and am just waiting until I get a cooler night to try it under the stars. The thing that's really cool with the 6mp sensor is that I can zoom in on details and move around to look at the target. Due to a vision problem I've got, I have always preferred color images, so video is the way to go.
The other thing that is on my list is to make everything lighter/quicker for portable use. An ATM buddy of mine has developed a computer that uses a memory card instead of a hard drive, so that makes it very light, and with low power consumption. This would facilitate the stacking/processing that others have mentioned in this thread. Add some light weight next generation lithium batteries to the mix.
If I remember correctly, don't some of the astrophoto processing programs have scripting languages (Maxim, PixInsight)? That might facilitate automating the collection/processing piece.
So, in the future, ads of commercial telescopes for amateurs will not only list aperture and focal length, but they will also list screen size...
Michael
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LXD-75 w/
Stellarvue 102ED
Hardin 10" Newt
Antares 8" Newt
Meade AR-5
Meade N-6
Celestron 102mm refractor
Canon 300D, Meade DSI guiding
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nytecam
Postmaster
Reged: 08/20/05
Posts: 5996
Loc: London UK
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Quote:
I agree that we're headed to less visual observing and more CCD/video displays. Combined with smart go-to, autofocusing, auto-centering, and real time image processing. There's also no reason to stay in the visual band either, but move into the UV and IR as the atmosphere bandpass allows.
Only the visual guys are transfixed in visual - been doing some near-IR via CCDs for over a decade and yes the massive Dob is unnecessary - I'm very happy with my 70mm, 90mm refrs; 90mm Schmidt and 30cm SCT in near-live imaging [below] despite horendous light pollution
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Nytecam 51N 0.1W
Meade 30cm LX200+ETX-70+e-finder+C8+Ha+CaK PSTs SBIG SGS+homebuilt spectrographs
Starlight SXVF_M9+Lodestar CCDs/Canon 300D DSLR/Hitachi HD+Disgo Video Fun cams
My observatory build-ETX-70 imaging-my videos
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Kobayashi
professor emeritus
Reged: 07/10/08
Posts: 742
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Quote:
I dont see the two as mutually exclusive, where general astronomy goes so goes ATMing.
By "general astronomy" do you mean commercial products for amateur astronomers, or research astronomy?
In either case, there are many things going on in research and commercial astronomical instruments that probably won't be popular for ATMs. For example, designing a camera takes considerable expertise and resources. Even multi-million dollar research astronomy projects often buy commercial cameras rather than developing custom designs. Designing a GOTO telescope is easier but that hasn't been a "revolution" in ATM either, unless you count retrofit kits. And of course research astronomers have access to space, which opens up wavelength regions amateurs can't touch for decades to come.
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Kobayashi
professor emeritus
Reged: 07/10/08
Posts: 742
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Quote:
Recently, a friend sent me a web link telling about professional astronomers using highspeed sensors to capture short moments of excellent seeing on large telescopes. I enjoyed telling him that amatuer astronomers have been doing this for years with web cams and getting fantastic planetary results.
Speckle interferometry is a well known technique, invented in the 1960s and used by many research astronomers since.
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cnstarz
professor emeritus
Reged: 12/22/07
Posts: 549
Loc: Kentucky, USA
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Quote:
Quote:
I dont see the two as mutually exclusive, where general astronomy goes so goes ATMing.
By "general astronomy" do you mean commercial products for amateur astronomers, or research astronomy?
In either case, there are many things going on in research and commercial astronomical instruments that probably won't be popular for ATMs. For example, designing a camera takes considerable expertise and resources. Even multi-million dollar research astronomy projects often buy commercial cameras rather than developing custom designs. Designing a GOTO telescope is easier but that hasn't been a "revolution" in ATM either, unless you count retrofit kits. And of course research astronomers have access to space, which opens up wavelength regions amateurs can't touch for decades to come.
Granted some things are impractical, but don't tell these folks ... Audine
You're very perceptive to mention access to space, with all of the competition between Govt's and private enterprise it may be possible sooner than you think. I believe if it can be done some ATM'er will give it a try eventually.
Cheers,
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mark cowan
Vendor (Obsidian Optics)
Reged: 06/03/05
Posts: 2316
Loc: salem, OR
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This thread looks for revolution for Amateur Telescope Makers... So...
Direct drive for GOTO and tracking. Dan Gray ( www.siderealtechnology.com) is reportedly close to rolling this out, and it's a considerable simplification which will surely be copied/adopted by ATMers.
Along that line, non-cogging steppers can be used to eliminate stepping pulses and simplify driving. That's not a revolution, except as a pun.
Personally, I think linear capacitative sensors to replace DSC encoders should become a big thing eventually. You can build them into any shape of structure, they're hugely accurate, don't have to sit on the axes, nonfouling.
Affordable/replicable adaptive optics systems. Matt Tudor's been working on this for some time using paralleled DSPs to do the heavy lifting in real time.
BTW, the "Lucky Imaging" system has a very fast and sensitive camera at its heart. This is a step above capturing video streams and picking out the best frames - it essentially freezes the seeing.
Carry on,
Mark
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rwiederrich
Goldfinger
Reged: 11/17/05
Posts: 8681
Loc: Bremerton Washington
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Quote:
This thread looks for revolution for Amateur Telescope Makers... So...
Direct drive for GOTO and tracking. Dan Gray ( www.siderealtechnology.com) is reportedly close to rolling this out, and it's a considerable simplification which will surely be copied/adopted by ATMers.
Along that line, non-cogging steppers can be used to eliminate stepping pulses and simplify driving. That's not a revolution, except as a pun.
Personally, I think linear capacitative sensors to replace DSC encoders should become a big thing eventually. You can build them into any shape of structure, they're hugely accurate, don't have to sit on the axes, nonfouling.
Affordable/replicable adaptive optics systems. Matt Tudor's been working on this for some time using paralleled DSPs to do the heavy lifting in real time.
BTW, the "Lucky Imaging" system has a very fast and sensitive camera at its heart. This is a step above capturing video streams and picking out the best frames - it essentially freezes the seeing.
Carry on,
Mark
Yes..but is this at all ATM=Amateur Telescope Making/er? Or just fancy electronics being geniously fashioned into just another *application*?
When I think of ATMing..I think of a guy in his garage making the parts (himself) for his DOB..GEM..Fork mount...Newtonian OT...refractive OT...etc etc etc. Not a guy who can assemble nifty electronics. Yes nifty electronics play a big part these days in ATMing..but it seams that we are drifting from Amateur Telescope Making to just assembling purchased componants and calling it so.
Rob
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www.goldmtobservingcenter.com
A great place for amateur astronomers, and ATM's to come and enjoy their hobby.
http://tech.groups.yahoo.com/group/HomemadeRefractorTelescopes/ My homemade refractor group.
www.vimeo.com/6014031
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mark cowan
Vendor (Obsidian Optics)
Reged: 06/03/05
Posts: 2316
Loc: salem, OR
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All being built by amateurs - so yes it's ATM, by definition. Advanced, OK.
Besides, the OP asked and I'm now talking about stuff that's built into amateur scopes, or could/will be. What's "the next revolution?" The electronics side of it has been going on for a long time now.
Look at Mel Bartel's alt-az drive systems. Thousands of hours of coding contributed by many people, all freely available. Plans (schematics, circuit board art) available online to build it yourself. How is that different from machining a gear? It's an electronic gear! With PEC you can get error well down below what any geared system offers.
And beyond that, some of the stuff I mentioned has serious advantages over the existing methods. To appreciate the value of cogless steppers you need to have seen how hard it is to get good torque and precision at the same time from ordinary steppers...
Some people make all kinds of stuff I wouldn't want to - EPs, flats, aluminizing chambers... It goes on and on - but it's hard to call what "a next revolution" could possibly be until it shows up and everybody starts doing it.
Best,
Mark
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rwiederrich
Goldfinger
Reged: 11/17/05
Posts: 8681
Loc: Bremerton Washington
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Quote:
All being built by amateurs - so yes it's ATM, by definition. Advanced, OK.
Besides, the OP asked and I'm now talking about stuff that's built into amateur scopes, or could/will be. What's "the next revolution?" The electronics side of it has been going on for a long time now.
Look at Mel Bartel's alt-az drive systems. Thousands of hours of coding contributed by many people, all freely available. Plans (schematics, circuit board art) available online to build it yourself. How is that different from machining a gear? It's an electronic gear! With PEC you can get error well down below what any geared system offers.
And beyond that, some of the stuff I mentioned has serious advantages over the existing methods. To appreciate the value of cogless steppers you need to have seen how hard it is to get good torque and precision at the same time from ordinary steppers...
Some people make all kinds of stuff I wouldn't want to - EPs, flats, aluminizing chambers... It goes on and on - but it's hard to call what "a next revolution" could possibly be until it shows up and everybody starts doing it.
Best,
Mark
Yes..I supose your right. If the application was designed and built for telescope application and or by ATMs themselves..then I can see your point.
I suppose I was talking about the situation where someone buys an OTA assembly..then the focuser they want, finder and such and assembles it all...places it on a heavely modified mount they pieced together and calls that ATMing.
To some that might be...to me it isn't.
Hey..by the way..did you get my PM?
Rob
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www.goldmtobservingcenter.com
A great place for amateur astronomers, and ATM's to come and enjoy their hobby.
http://tech.groups.yahoo.com/group/HomemadeRefractorTelescopes/ My homemade refractor group.
www.vimeo.com/6014031
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refractory
Pooh-Bah
Reged: 02/05/05
Posts: 1263
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Deja Vu all over again...
I suppose it all depends upon where one wants to draw the line on raws vs. parts vs. finished products/modules. You aren't exactly cooking up your own GLASS- you get that from somewhere else. You don't make your screws (people used to, back in the day), or refine your own metals or mix alloys. Or perhaps you DO? Done any elemental nucleosynthesis lately? Fusion cuisine!
Even Mother Nature uses the same material and processual modules over and over again- much more efficient than having to reinvent or reengineer each time. And she's not above giving up the old and adopting the new when it does a better job of things- even lifting them out of organisms wholesale and plonking them down in others.
Me, I can't wait til we have negative refraction materials to play with, giant lightweight full color photomultipliers, etc., and more open minds generally.
Jess Tauber
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Jeff Morgan
Carpal Tunnel
Reged: 09/28/03
Posts: 2080
Loc: Prescott, AZ
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Quote:
I'll take the mosquitos, dewing, and star-hopping, thank you, and remain a militant visual observer.
Ross
In terms of the electronics, this hardly qualifies as amateur-made anymore than buying a Schmidt-Cass qualifies as ATMing. Sure, a very few highly talented individuals may piece together some devices from ready made components. But no one will be manufacturing silicon wafers in the garage. At least working glass, metal, and wood will remain something accessible to a large slice of the astro-community.
In reading this thread over, I have been coming up with blanks as far as where the hobby can go. I think the Dob/ultralight/portable revolution has gone about as far as it can. Perhaps the pendulum is ready to swing back to fixed installations, added by electronics to get past sky glow. How about:
1) Convenience. Another post refers to "house scopes" or the use of flats to create more ergonomic scopes and/or observatories.
2) Unobstructed reflectors via tilted primaries and toric secondaries. Jose Sasian wrote these up nearly two decades ago. It would seem a challenge, but not insurmountable.
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Jeff Morgan
Prescott, AZ
Wile E. Coyote School of Telescope Making
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Gene Hunter
sage
Reged: 12/29/07
Posts: 292
Loc: SC
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Carbon Fiber mirrors that are cheap, fast and no cooldown time. Also Carbon Fiber Tubes, spiders and the mirror cell will be literally part of the mirror.
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Clear Skies
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gregj888
sage
Reged: 03/26/06
Posts: 318
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Think how much energy we could save if we turned all the light off at night... With the price of energy going up and motion sensors down, the next big thing could be deep sky observing from your drive way...
It's a thought anyway...
greg
PS, not meant as a political statement, just pointing out an interesting possibility...
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mark cowan
Vendor (Obsidian Optics)
Reged: 06/03/05
Posts: 2316
Loc: salem, OR
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Quote:
I suppose it all depends upon where one wants to draw the line on raws vs. parts vs. finished products/modules. You aren't exactly cooking up your own GLASS- you get that from somewhere else. You don't make your screws (people used to, back in the day), or refine your own metals or mix alloys. Or perhaps you DO? Done any elemental nucleosynthesis lately? Fusion cuisine!
Yeah, the Martha Stewart approach to ATMing - first you have to make the sand.  OTOH the John Dobson method runs (and I quote) "Well, first you get the Navy to scuttle a battleship."
But this is just semantics - "my ATM is more ATM than your ATM" - which is kind of silly. I like novel ideas that allow you to build something better or easier or so that it works better, and a lot of dob techniques that have come along in the last 10 years or so are just that - flex rockers, string scopes, spring counterweights, stuff like that. The party isn't over yet.
I've never met anybody that made their own screws, maybe that's before my time. But I prefer to build assemblies with tapped holes whenever possible to avoid extra fasteners. And I'll thread pieces as well, so maybe that qualifies. But no, I don't make the alloys - I just buy them at my local metal scrapyard.
Quote:
Me, I can't wait til we have negative refraction materials to play with, giant lightweight full color photomultipliers, etc., and more open minds generally.
You'll be waiting one heck of a long time for any of those in useful sizes, although the last one is an individual choice probably beyond your control. What exactly is a "full color photomultiplier", if you don't mind my asking?
No offense intended,
Mark
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kim marie
member
Reged: 02/23/07
Posts: 39
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Hi All,
Mind controlled Telescope using a Emotiv headset, controlling ScopeDriver software, to run your telescope.
http://www.emotiv.com/
http://www.aquiladigital.us/scopedriver/
The headsets are not out yet, gives you time to get into a sidereal state.
Regards
Bruce
http://bellsouthpwp2.net/b/r/brucehegerberg/
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Bruce Hegerberg
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RossSackett
scholastic sledgehammer
Reged: 08/17/07
Posts: 756
Loc: Memphis, TN
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Quote:
Mind controlled Telescope using a Emotiv headset, controlling ScopeDriver software, to run your telescope
Anyone else reminded of the movie Wall-E?
It is understandable that in a gear-oriented forum such as this one that our vision of future trends is dominated by developments in electronics and exotic materials.
But the great revolution instigated by Dobson and his merry band wasn't just about big cheap reflectors on a new kind of mount. It was also about a different kind of observing--not imaging by junior scientists with their backyard mini-Palomars, but a sort of passionate visual skywatching that had big emotional, philosophical, and perhaps spiritual impacts on the mind at the eyepiece. "Showing people the universe they live in" became the catch-phrase: astronomy impacting people's lives by forever broadening their worldview.
I can see how the high tech developments discussed so far could appeal to the junior scientist in all us ATMs, but I don't see the potential in any of them to make a real difference in the world beyond our shrinking community of gearheads.
As I see it, the real challenge with be outreach, not equipment, and the lines of growth we've outlined so far won't help much with that. West coast ATM Gil McFarlane's daughter reported on a great experiment at RTMC 2007. She showed her classmates a Hubble photo of Saturn, then let them see the planet with their own eyes through a scope she built herself. The photo had no impact on them; the blurry, shifting view at the eyepiece blew them away.
I sure hope the Dobsonian revolution isn't over, as some seem to think. Brain-controlled imaging platforms may be cool to think about, but I fear such developments just increase our irrelevance and accelerate the demise of our wonderful avocation. It isn't that we shouldn't explore such growth points, but that we need to be careful not to lose what we have in the process.
Just my grumpy POV.
Ross
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"A craftsman relies on science when the state of knowledge allows it, tradition and experience when it does not, and makes art whenever he can."
12 scopes from 4.25 to 18" and a 24" in progress. 12 ATM awards. Webpage: http://stardazed.com/ Some more scope pix at http://www.flickr.com/photos/8315630@N04/
Anagrams: Amateur astronomer = A mature moon-starer; Dobsonian maker = Debonair as monk
Edited by RossSackett (08/14/08 04:07 PM)
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Stefan Rostyne
Pooh-Bah
Reged: 10/19/04
Posts: 1011
Loc: Assenede, Belgium
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I second that!
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Stefan Van de Rostijne
4.5" F4.5 newt 5°widefield/finderscope
8" f/5.6 travel dob
old 12.5" F5 dob (used to look better...)
30 cm f/30 Classic Cassegrain (polishing primary)
23" f/4 dob project
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llanitedave
Humble Megalomaniac
Reged: 09/26/05
Posts: 13776
Loc: Amargosa Valley, NV, USA
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Quote:
Just my grumpy POV.
Ross
I call that wisdom!
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"Since the process of science generates more mysteries than it solves, we can never learn everything, we'll simply generate new ignorance at the speed of knowledge."
"S.O.E." (Sauron's Other Eye), with 16" Royce conical mirror: A permanent work in progress.
10" Homebuilt dob, old Coulter mirror
Under Construction: The "Eye of Sauron" Observatory!
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gregj888
sage
Reged: 03/26/06
Posts: 318
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Ross, "I sure hope the Dobsonian revolution isn't over"
From an ATM perspective, ya I think it's pretty dead. Actually I'm not sure it was ever alive in a broad sense. "Scrap a battleship" for the glass, dumpster dive for some PVC flanges, when's the last time you saw a vinyl record, then find some scrap wood... Ebony Star, aluminum sectors, computer control do-to to my mind are Alt-Az scopes (vs. a "Dob") at least I draw the distinction.
If you mean sidewalk astronomy, I think that's alive and well. We had a "Star Party" here in Portland Monday night for the meteor shower. Along with just looking, there were 30+ scopes setup for public viewing. Just guessing, 500 or so visitors but the number could have been a lot higher.
My "Star Party scope" is a 6" trischiefspiegler (made of re-cycled stuff, shades of John...). I'm grinding the glass for a 4" Dave Groski schiefspiegler for the same use. Still working on the 20" with AO, so have at least one foot firmly in the "mini Palomar" camp.
The 6" gets a lot of attention at the star parties. We could see Io's transit and the turbulence in the bands Monday night. 4" to 8" TCTs seem to be coming back in vogue and might be a place to watch.
Greg
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RossSackett
scholastic sledgehammer
Reged: 08/17/07
Posts: 756
Loc: Memphis, TN
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Greg,
I think you may have missed the point of my rant. So far the discussion has focused on the high-tech side of the hobby, which I am predicting will be lots of fun for us, and have almost no impact outside our narrow circle. As far as "alt-az" vs. Dobs, I think you are in a minority--I think most of us consider Ebony Star and its successors, ServoCats, and trusses useful but incremental improvements on the basic dob pattern, and part of the on-going Dobsonian movement.
I am delighted you had a good turn-out for your public star party--we need more successes like that. Most of the astronomy conventions are having a lousy year, and it is reassuring that outreach is still a draw in some places. Unfortunately not in others, like Memphis.
Do you really think Schiefs and Schups are poised for a breakout? I love the crisp high power images, but they strike me as narrow-niche scopes. It would surprise me, but it could happen. They have been increasing in popularity at Stellafane the last few years, but this year there didn't seem to be very many of them.
Best,
Ross
Edited by RossSackett (08/14/08 03:59 PM)
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RossSackett
scholastic sledgehammer
Reged: 08/17/07
Posts: 756
Loc: Memphis, TN
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p.s. I didn't intend to pick on Bruce's post on brain-controlled scopes--that is a very cool idea! Or a similar idea, detecting eye movements to automatically center the scope on the part of the image that is drawing our attention. This would make guiding and exploring an entirely intuitive process. An innovation like that might re-invigorate visual observing, undermining my earlier thesis on the "two cultures" of passionate visualists vs. backyard Palomar imagers.
Ross
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"A craftsman relies on science when the state of knowledge allows it, tradition and experience when it does not, and makes art whenever he can."
12 scopes from 4.25 to 18" and a 24" in progress. 12 ATM awards. Webpage: http://stardazed.com/ Some more scope pix at http://www.flickr.com/photos/8315630@N04/
Anagrams: Amateur astronomer = A mature moon-starer; Dobsonian maker = Debonair as monk
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gregj888
sage
Reged: 03/26/06
Posts: 318
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Ross,
I didn't draw the Alt-Az/Dob distinction until I spent a little time around John Dobson at a RTMC a few years ago. I wasn't trying to start a fight either but was making a point. The "true Dob" never went very far in the ATM world. The small commertial scopes are much closer to the original. I have the old Gleaning article around here someplace... it's pretty interesting and worth hunting up. That said, I do appriceate what John Dobson really did which was to change attitudes, not really a scope design.
As far as the TCTs, yes. Dave's design is about as easy to make as you get. If the performance is as good as I hear, it should be a winner. Where you have dark sky's, the big scopes win... Where you are limited to the moon and planets, the little TCTs show very very well. They are also cheap to make, easy to transport and store.
This weekend I had the scope halfway taken down and the line reformed... My wife was sleeping in the lawn chair so set it back up and stayed an extra hour or so.
As far as big moves in the hobby, remote scopes seem to be the way the high end is headed. Place the scope in a dark location and maybe, never see it. I have my 10 acres outside of Bend Oregon (about 2 miles south of Argo if that's familiar). I hope to put the 20" there some day. It will have a camera and maybe an AO system, but will also have eye pieces.
Lot's of room in the hobby to go different ways. All good stuff.
Greg
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RossSackett
scholastic sledgehammer
Reged: 08/17/07
Posts: 756
Loc: Memphis, TN
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Greg,
You didn't say it, but I agree with the implication that Dobson himself is something of a "complex" character when it comes to telescope making. He gave us a catalytic design that started an adaptive radiation of big alt-az scopes, each departing farther and farther from his original pattern, but all tracing direct descent from those early "circus cannons." At RTMC, Stella, and the other scopemaker's conventions you still see lots of recently-built 8-10" instruments sticking closely to the original "sidewalk" design, but you never see the really big cardboard tube scopes anymore. Dobson hasn't seemed particularly interested in the new directions dobs have taken, at least when I have seen him in the last few years.
Good luck on that 20"
Ross
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"A craftsman relies on science when the state of knowledge allows it, tradition and experience when it does not, and makes art whenever he can."
12 scopes from 4.25 to 18" and a 24" in progress. 12 ATM awards. Webpage: http://stardazed.com/ Some more scope pix at http://www.flickr.com/photos/8315630@N04/
Anagrams: Amateur astronomer = A mature moon-starer; Dobsonian maker = Debonair as monk
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gregj888
sage
Reged: 03/26/06
Posts: 318
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Ross,
"Complex" maybe less than "character" but that's a good place to leave it. What John Dobson did was to say it's ok the use an alt-az scope for astronomy. Then he proved it to the point that no one could argue. For that, his fame is just and worthy (IMHO, which doesn't count for much:-).
You're right too on the 8" to 10" scope, though most of those builders have purchased their wood ;-)
Greg
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mark cowan
Vendor (Obsidian Optics)
Reged: 06/03/05
Posts: 2316
Loc: salem, OR
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Well, as you say, there's "lot of room in the hobby to go different ways." 
When John introduces his classes to what they're going to build, he makes note of the two (or three) separate parts of the "revolution" - (1) making large mirrors cheaply, (2) making a mount to support them properly, also cheaply, (3) by virtue of (1) and (2), arriving at a working scope of decent size to show a lot of objects in a time frame that most people can handle, with skills most people can tap, regardless of their background. (1) without (2) is no good, nor is the reverse. If the scope never gets finished you don't get to (3) and that's why KISS is so useful in that approach.
You can't really call it a "revolution" in modern times, as for large portable aperture some variant of a dobsonian based design is essential.
The OP said:
Quote:
So, my question is, in the next 10 years, what will the likely breakthroughs be?
Personally, I think that materials science is getting to the point where a thin, inexpensive, carbon-fiber-like mirror will be made for the masses. I also expect that deformable mirrors will become available for the average joe.
Note that neither of these two are explicitly ATM - he's not suggesting people will build their own carbon-fiber mirrors, which strikes me oddly. So far the research that applies here is dedicated to replicated mirrors, which require an inverse curved mandrel to form the carbon-fiber replica on. Not easy at all. And not inexpensive, given that the mandrel is only good for about 10 replications. Spin-casting some sort of epoxy is much more promising for forming cheap accurate paraboloids, and 10 years is probably about the right time frame to see that happen. But it hasn't happened yet in reality except for relatively low surface tolerances, not good enough for visual use.
Deformable mirrors (as in active optics I take it) necessarily has meant for the last 15 years at least extremely expensive fast actuators, coupled with fast hardware to drive them, and though you could spin variations on this - say mylar membranes with some form of electrostatic positioning - it doesn't exist yet. 10 years again would probably see it happen, it's been done (or at least proposed) for space borne applications. Could be cheap. Search the net for projects so far.
Here's one for free, y'all. The metal gallium is an excellent reflector, fairly inexpensive, and melts just a little above room temp. When it freezes out it crystallizes and expands. A thin layer on glass makes a decent mirror though. The proper alloy with any of quite a few other metals (which nobody knows what it would be or even if it could be made) might be able to alter both the melting point and the expansion on freezing to make a material which could be melted at 50 degrees C, spun into a perfect paraboloid on a proper support, and hardened into a world-class mirror, essentially for pocket change. Recoating? Just reheat and respin it. You can build an air-bearing turntable and oven to accomplish this in your garage. Size would be no barrier.
How to solve the alloy issue, or find if it can be solved? A physicist I know who did his PhD dissertation on gallium crystal structure eventually told me he didn't think it could be done. But he wasn't 100% sure.
Beowulf clusters, basically, with adaptive software that tries vast numbers of likely (and unlikely) combinations, predicting structure and phase change. Drawback is that predicting detailed phase change properties from bulk behavior is among the hardest materials science problem around. Possibly flash freezing - if the crystals are smaller than about 50nm and there's no density change on freezing you should have a good optical surface. Gallium supercools easily though and requires seeding to crystallize. Build that into the substrate...
How long to work this one out? I don't know. How fast do you think your desktop PC will be come 2018, hmmm?
Best,
Mark
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Chriske
Kijkerbouw Urania
Reged: 08/15/04
Posts: 2160
Loc: Boechout, Belgium
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Quote:
Size would be no barrier....
Mark
Strong point, mankind is busy poluting the atmosphere so badly we will actually need those large mirrors in a few decades from now...
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Chris
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Ed Jones
Pooh-Bah
Reged: 04/06/04
Posts: 1477
Loc: Sin-sin-atti
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Here's another wacky idea, glass foam. It's very rigid, light weight easily shaped. If somehow you could put a reflecting layer on it you would have an extremely light weight mirror.
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Ed Jones
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Chriske
Kijkerbouw Urania
Reged: 08/15/04
Posts: 2160
Loc: Boechout, Belgium
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wacky....? What about this one..?
We're busy flexing mirrors like Mr Adler told us. Works just fine.
But what would happen if a sheet of plate glass, say 2, 3 or 4 mm thick (assuming it is flat) would be flexed without even grinding and polishing it. (How far) Could a very thin sheet of glass be flexed to a parabola...? And to make things easier heating the glass a bit to make it soft and more willing.
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Chris
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jayscheuerle
Post Laureate
Reged: 01/16/06
Posts: 4263
Loc: S. Philadelphia, PA
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Chris, I'd imagine the supporting ring would have to be a very accurate circle. Could one flex it with a vacuum?
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Fight indignorance!
120ED, 12" f/5 Green Goblin, 6" f/5 Eero2, 4.5" f/8 PortaBowl, 8" f/5 Big Red Ed.
The PortaBowl-a $100 4.5" f/8 ball-scope YOU can build!
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DAVIDG
Carpal Tunnel
Reged: 12/02/04
Posts: 2141
Loc: Hockessin, De
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Quote:
Chris, I'd imagine the supporting ring would have to be a very accurate circle. Could one flex it with a vacuum?
The problem with a vacuum method is that a flat glass plate doesn't form a parabola, it forms a third order curve. This is how Schmidt correctors are made.
On that same idea, it might be possible to have small flexible lens to make actively controlled eyepieces that corrects for atmospheric problems and/or optical problem in the 'scope in real time. One might see something at Stellafane in a year or two, hint, hint
- Dave
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Homemade 'scopes 8"f/7,6" f/5", 6"f/4, 4.25" Schief. 60mm Coronagraph,60mm H-alpha system, 4.25" White-light Solar Newtonian,solar spectroscope, 4" f/12, 4.5" f/16 & 6" f/12 Schupmann Medial refractors, 14 Stellafane awards 7 in optics
Engineering = Taking what you have and making what you need.
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Chriske
Kijkerbouw Urania
Reged: 08/15/04
Posts: 2160
Loc: Boechout, Belgium
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Quote:
One might see something at Stellafane in a year or two, hint, hint
- Dave
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Chris
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RossSackett
scholastic sledgehammer
Reged: 08/17/07
Posts: 756
Loc: Memphis, TN
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Quote:
[...it might be possible to have small flexible lens to make actively controlled eyepieces that corrects for atmospheric problems and/or optical problem in the 'scope in real time. One might see something at Stellafane in a year or two, hint, hint
Dave,
So I shouldn't harvest the liquid prisims from my Canon binocs to hack that motion compensator just yet?
Seriously, for next summer I was thinking of a 24" single pole with motion compensation, active vibration suppression, and automatic collimation adjustment. If you are working on motion and seeing compensation, I'll leave that off 
Ross
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"A craftsman relies on science when the state of knowledge allows it, tradition and experience when it does not, and makes art whenever he can."
12 scopes from 4.25 to 18" and a 24" in progress. 12 ATM awards. Webpage: http://stardazed.com/ Some more scope pix at http://www.flickr.com/photos/8315630@N04/
Anagrams: Amateur astronomer = A mature moon-starer; Dobsonian maker = Debonair as monk
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DAVIDG
Carpal Tunnel
Reged: 12/02/04
Posts: 2141
Loc: Hockessin, De
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Ross,
Keep working on your design. What your doing sounds like mechanical compensation for vibration in the telescope itself. I'm playing around with a real time adaptive optics that will run off a laptop. If I can achieve a 10% or great improvement it the image quality, I think I'll have something.
You build your 'scope and I'll plug in my eyepiece and we'll see how long the line forms to take a look on the 'Hill'.
- Dave
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Homemade 'scopes 8"f/7,6" f/5", 6"f/4, 4.25" Schief. 60mm Coronagraph,60mm H-alpha system, 4.25" White-light Solar Newtonian,solar spectroscope, 4" f/12, 4.5" f/16 & 6" f/12 Schupmann Medial refractors, 14 Stellafane awards 7 in optics
Engineering = Taking what you have and making what you need.
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Michael Miles
professor emeritus
Reged: 02/11/05
Posts: 677
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Quote:
...not imaging by junior scientists with their backyard mini-Palomars...
Actually, I am a Jr. Scientist (working at a scientific research firm), and I am building a mini-Palomar (see my posts) for imaging.
I helped build my first telescope at age 14, and machined my first telescope and mount at 18. I kind of thought the next revolution would be cheap Chinese metal machining tools (certainly was for me). Seems like metal machining is too intimidating from the feedback I've seen elsewhere - too bad.
GOTO and Sky Scout have been a revolution for public astronomy, but they're not normal ATM pastimes.
I'm an ATM because I like designing and building prototypes of my ideas, and it's fun. Hadn't really thought about whether it was socially relevant.
Michael
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LXD-75 w/
Stellarvue 102ED
Hardin 10" Newt
Antares 8" Newt
Meade AR-5
Meade N-6
Celestron 102mm refractor
Canon 300D, Meade DSI guiding
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refractory
Pooh-Bah
Reged: 02/05/05
Posts: 1263
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With regard to Mark Cowan's suggestion of Gallium alloys- if we go nano-scale, with containment? We want to avoid oxidation, and at nano scale crystallization might be avoided (but what about reflective properties?). If the particles were encapsulated (say in silica or some other material) one might avoid oxidation or other chemical changes. Then one could simply coat a surface with a sprayer or something.
Me, I've been thinking about cheap, transparent, tough substrates for ultrathin gradient index lenses. There are diamond coatings for knives and other tools. If one could make an ablatable ultraflat surface (say of dry ice or something that would liquefy when heated) and then coat, you would end up with a diamond sheet. Could this be used on a parabolic mandrel? Then you could have diamond mirrors. If thin enough, it might not fracture the same way as bulk diamond crystals do. Support, flex might be very easy.
Plus telling the girls the scope has diamonds might increase their interest....
Jess Tauber
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Joe Cipriano
Entropy Personified
Reged: 09/03/05
Posts: 3893
Loc: Uh... anyone have a GPS?
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Quote:
...Seems like metal machining is too intimidating from the feedback I've seen elsewhere - too bad.
How about blank machining?
Take one of these, attach a computer-controlled rotary table mounted horizontally on the bed, and program the controller to generate a curve on your blank. I don't know a ton about machining, so I'm not sure if the appropriate glass-grinding bits are currently available, but I'd imagine something could be adapted to the purpose.
A CNC lathe might be better in this application, but you'd need a big lathe to work blank larger than 8".
--------------------
In the Land of Eternal Light Pollution & Great Pizza (Chicago)
SN-6, ED80, WO 66SD
Meade 208xt, SBIG ST-4
D70 (modified)
CGE (way modified)
A Wife who understands (unmodified)
Some other stuff...
The best introduction to astronomy is to think of the nightly heavens as a little lot of stars belonging to one's own homestead.
George Eliot
Edited by Joe Cipriano (08/15/08 02:37 PM)
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Michael Miles
professor emeritus
Reged: 02/11/05
Posts: 677
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My Roboscope buddy here in Raleigh converted a Harbor Freight mini-mill himself to a CNC unit. I think a specialized machine might work better for blank grinding, but you could build one of those with the mill .
How you been Joe - been a while since we've been on a thread together? You were a part of the most recent revolution - fixing up cheap Chinese telescope equipment.
Michael
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LXD-75 w/
Stellarvue 102ED
Hardin 10" Newt
Antares 8" Newt
Meade AR-5
Meade N-6
Celestron 102mm refractor
Canon 300D, Meade DSI guiding
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amper
journeyman
Reged: 07/18/08
Posts: 7
Loc: FM29LW
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Quote:
I helped build my first telescope at age 14, and machined my first telescope and mount at 18. I kind of thought the next revolution would be cheap Chinese metal machining tools (certainly was for me). Seems like metal machining is too intimidating from the feedback I've seen elsewhere - too bad.
The question, at least for me, isn't whether or not machining is too intimidating, it's where do you get access to the machinery and someone to teach you how to use it? After all, it doesn't make sense to invest money in machinery, even cheap machinery from China, if you don't already know how to use it, or have immediate access to a good mentor.
Do schools even have shop classes anymore? Kids these days aren't learning any skilled trades in the public school system that I can see. At 40 years old (well, in December, anyway), I think I may be from the last generation who remembers what its like to actually build something for yourself from scratch. Most of the guys I know don't even own tools, and most of the women can't cook to save their lives!
We've lost far too much practical knowledge already in general society, and modern society is structured such that very few people can afford the time, let alone the money, to pursue even one hobby.
--------------------
Have: 2x Pentax PIF 7x50
Want to build: 8" f/6 hyperbolic Newtonian binocular telescope
Want to buy: Nikon 20x120 Binoscope, Pentax PIF 10x50
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llanitedave
Humble Megalomaniac
Reged: 09/26/05
Posts: 13776
Loc: Amargosa Valley, NV, USA
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I think Michael's on to something. We ARE now in the midst of a revolution in the availability of homebuilt computer controlled CNC machining tools. In theory, one can be programmed to create a part of just about any shape at a very high precision. If this catches on among ATMers, we can end up with some very unusual and beautiful designs.
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"Since the process of science generates more mysteries than it solves, we can never learn everything, we'll simply generate new ignorance at the speed of knowledge."
"S.O.E." (Sauron's Other Eye), with 16" Royce conical mirror: A permanent work in progress.
10" Homebuilt dob, old Coulter mirror
Under Construction: The "Eye of Sauron" Observatory!
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Michael Miles
professor emeritus
Reged: 02/11/05
Posts: 677
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Quote:
... We ARE now in the midst of a revolution in the availability of homebuilt computer controlled CNC machining tools. In theory, one can be programmed to create a part of just about any shape at a very high precision. If this catches on among ATMers, we can end up with some very unusual and beautiful designs.
Hmmm, I've seen professional machining web sites that use online CAD software to place orders for custom parts. I even used one to justify buying my own machine tools (the tools were cheaper). Maybe some of those CNC machining hobbyists can make a few extra dollars wth a similar scheme since their machines are sitting idle most of the time. This could be one of the paths for some of them to turn hobby into profession. For others, it can make the hobby pay for itself.
I'll email my buddy and see if he'd be interested in offering that service.
As an alternative to specialized online CAD software, maybe some freeware software could be offered. Of course, the intellectual property issues could be sticky as to who owns designs, but I think having clear options worked out up front would help.
Interesting idea,
Michael
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LXD-75 w/
Stellarvue 102ED
Hardin 10" Newt
Antares 8" Newt
Meade AR-5
Meade N-6
Celestron 102mm refractor
Canon 300D, Meade DSI guiding
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PrestonE
Pooh-Bah
Reged: 04/29/05
Posts: 1193
Loc: Houston,Texas
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Dave, It's already being done. Take a look at our 20 Inch RC thread and the use of the CNC Router to cut the carbon/aramid fiber spider vanes...
Once my CNC mill is back up and running, I've got a CNC lathe started...
Then we will be rocking...
Regards,
Preston
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A few I enjoy,
and a few more in the works ;<)
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Michael Miles
professor emeritus
Reged: 02/11/05
Posts: 677
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Quote:
...
We've lost far too much practical knowledge already in general society, and modern society is structured such that very few people can afford the time, let alone the money, to pursue even one hobby.
Yea, I kind of agree with you. Recently, I was sitting around with a bunch of guys my age, and we were reminiscing about working on farms in the summer and fixing up cars. One of the more poetic of us remarked that we may be the last generation that could make those claims. Kinda made me sad.
The local community colleges do offer machining classes, but they're all about CNC technology. Pretty soon, only robots and androids will be allowed to sign up for the classes...
Michael
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LXD-75 w/
Stellarvue 102ED
Hardin 10" Newt
Antares 8" Newt
Meade AR-5
Meade N-6
Celestron 102mm refractor
Canon 300D, Meade DSI guiding
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George N
scholastic sledgehammer
Reged: 05/19/06
Posts: 777
Loc: Binghamton & Indian Lake NY
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Quote:
wacky....? What about this one..?
We're busy flexing mirrors like Mr Adler told us. Works just fine.
But what would happen if a sheet of plate glass, say 2, 3 or 4 mm thick (assuming it is flat) would be flexed without even grinding and polishing it. (How far) Could a very thin sheet of glass be flexed to a parabola...? And to make things easier heating the glass a bit to make it soft and more willing.
Not a “wacky idea”, it was tried back in the 1980’s.
I use to work for the US DoD and worked with what was then the giant of the flight simulator industry. At that time flight simulators used large short F/ratio mirrors to put the images into the simulator’s cockpit windows. This company invested millions in an IR&D project lead by a Physics PhD to try and form F/2 or so parabolic mirrors in the 20 to 30 inch size from heated vacuformed thin glass sheets. Even getting close and then going to traditional mirror making was a goal. After spending several years on it, they concluded it wouldn’t work and dropped the project.
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George N
Obsession 20
Optical Guidance Systems 10" F/9 R-C Cass
6" F/5 & 8" F/8 home-made Newts
MI-250 mount
SBIG STL-1301E CCD
Member, International Dark-Sky Association
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George N
scholastic sledgehammer
Reged: 05/19/06
Posts: 777
Loc: Binghamton & Indian Lake NY
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Quote:
......Very large aperture Cassegrain and Nazmith dobsonians. Size limit would likely be the vehicle used to transport it......
-Tim.
About five years back a guy had an ATM 16-inch Ritchey-Chretien at Stellafane that used a third flat mirror to put the focus out the center of the alt/az altitude bearing. The primary was not center cored, and the eyepiece was always located at sit-down height, although the observer would have to move his chair after a large az move. The scope itself was made from pop-riveted square aluminum tubing. I believe the scope won first prize in ‘mechanical’, but poor weather prevented the ‘optical’ contest.
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George N
Obsession 20
Optical Guidance Systems 10" F/9 R-C Cass
6" F/5 & 8" F/8 home-made Newts
MI-250 mount
SBIG STL-1301E CCD
Member, International Dark-Sky Association
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Michael Miles
professor emeritus
Reged: 02/11/05
Posts: 677
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Of course, if we farm out our CAD CNC work, then we won't be ATM'ers anymore, we'll be AT-Designers...
Michael
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LXD-75 w/
Stellarvue 102ED
Hardin 10" Newt
Antares 8" Newt
Meade AR-5
Meade N-6
Celestron 102mm refractor
Canon 300D, Meade DSI guiding
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jayscheuerle
Post Laureate
Reged: 01/16/06
Posts: 4263
Loc: S. Philadelphia, PA
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Quote:
Of course, if we farm out our CAD CNC work, then we won't be ATM'ers anymore, we'll be AT-Designers...
Michael
Which is equally, if not more important.
Almost anybody with a decent set of plans and a modest tool-set can make a dob. The K&B bible is good for this.
But making the scope isn't what starts a revolution. It's innovative design that does that. Of course, unless your innovative design is easy to make, it's never going to gain the momentum to become revolutionary unless a manufacturer picks up on it.
Personally, I'd be more than happy to let an ATMer work up my ATDs, but I couldn't afford to pay someone to execute at the quality level I'd want. So, it takes me 10 times as long to do it myself...  - j
--------------------
Fight indignorance!
120ED, 12" f/5 Green Goblin, 6" f/5 Eero2, 4.5" f/8 PortaBowl, 8" f/5 Big Red Ed.
The PortaBowl-a $100 4.5" f/8 ball-scope YOU can build!
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mark cowan
Vendor (Obsidian Optics)
Reged: 06/03/05
Posts: 2316
Loc: salem, OR
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Quote:
If the particles were encapsulated (say in silica or some other material) one might avoid oxidation or other chemical changes. Then one could simply coat a surface with a sprayer or something.
But it leaves you with needing to make a surface, though. Spinning a metal mirror automatically produces a paraboloid... Solving it and patenting the solution would be worthwhile commercially, anybody can build their stuff for personal use using anybody else's patent for free...and that would be ATM. Also (a small note here) Ga2O3 should be a transparent film (like AlO2), and GaInO3 is transparent. Testing the bulk solid material for oxidation response is easy.
Gallium when liquid oxidizes matte rapidly - here's a patent description for treating the surface of liquid gallium mirrors to prevent this: US Patent 6544353 - Surface chemical treatment for liquid gallium or gallium alloy mirrors. They also find the passivating (modified) oxide layer must have defects smaller than about 40nm to work as a mirror... What is also interesting is the description of cleaning the liquid mirror before treating it to remove all oxides present with hydrochloric or hydrobromic acid  , after which they apply the passivating layer and let it react.
A final note from Wikipedia:
Quote:
One chemist estimated in 2007 that at the current rate of usage, the world's supply of gallium would be exhausted by about the year 2017.
Uh-oh!
Best,
Mark
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refractory
Pooh-Bah
Reged: 02/05/05
Posts: 1263
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NO MORE GALLIUM??!! I guess we better get Rob working on that nucleosynthesis after all! Or we could mine Gallium on Mercury (ironic, or is that ionic?). Mother Nature has kindly blown away her upper crust leaving the core much closer to the surface. My company has first dibs on precious metals (and air conditioned suits..).
Wasn't Ermanno Borra up at Laval working on gallium too, aside from his mercury fume breathing obsession?
HA! Solid mirrors, liquid mirrors- I have you all beat. GAS and PLASMA! We land on the Sun at NIGHT!
Actually some of the recently discovered ionic liquids seem interesting- maybe we could trick them into assuming parabolic monolayers? Then making mirrors would be as easy as blowing bubbles.
One idea that came to mind, from the Sci-Fi Ringworld universe, was a mirror made from a single molecule (as in General Products hulls). The idea here would be to crosslink either a single strand that was coiled zillions of times around itself (like a native basket bottom), or I suppose I can wait till they have large monolayers of graphite.
Now Rob is squirming- Like HAL in 2001 being de-memoried, I can feel it. Daisy, Daisy......
Jess Tauber
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Jeff Morgan
Carpal Tunnel
Reged: 09/28/03
Posts: 2080
Loc: Prescott, AZ
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For those of you old enough to remember that late 1970's, the "experts" said all oil reserves would be exhausted in five or ten years.
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Jeff Morgan
Prescott, AZ
Wile E. Coyote School of Telescope Making
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refractory
Pooh-Bah
Reged: 02/05/05
Posts: 1263
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Well, if you're intent on turning us into the next Venus with greenhouse emissions, we can always mine hydrocarbons on Titan. Nobody will mind if there is a spill along the way, either. Just try not to pick up any chest-busting alien embryos while you're at it, OK Ripley?
Jess Tauber
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jdownie
scholastic sledgehammer
Reged: 02/24/06
Posts: 910
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Post deleted by jdownie
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ATM project - a terrible waste of good Pyrex.
Edited by jdownie (08/17/08 11:51 AM)
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llanitedave
Humble Megalomaniac
Reged: 09/26/05
Posts: 13776
Loc: Amargosa Valley, NV, USA
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The warning, of course, is an indication that we need to support efforts to develop more reserves. This is true for a large number of relatively unknown but vital metal and mineral resources. A lot of people don't like the mining industry, and would be happy (for a short while) if all the mines were shut down, but when society shuts down as a result, they're likely to change their minds.
--------------------
"Since the process of science generates more mysteries than it solves, we can never learn everything, we'll simply generate new ignorance at the speed of knowledge."
"S.O.E." (Sauron's Other Eye), with 16" Royce conical mirror: A permanent work in progress.
10" Homebuilt dob, old Coulter mirror
Under Construction: The "Eye of Sauron" Observatory!
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jayscheuerle
Post Laureate
Reged: 01/16/06
Posts: 4263
Loc: S. Philadelphia, PA
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So the next ATM revolution has to do with oil reserves?...
--------------------
Fight indignorance!
120ED, 12" f/5 Green Goblin, 6" f/5 Eero2, 4.5" f/8 PortaBowl, 8" f/5 Big Red Ed.
The PortaBowl-a $100 4.5" f/8 ball-scope YOU can build!
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Michael Miles
professor emeritus
Reged: 02/11/05
Posts: 677
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Quote:
...Just try not to pick up any chest-busting alien embryos while you're at it, OK Ripley?
Jess Tauber
Actually, chest-bursting aliens adapted to gestating in our biochemistry would imply common origins with earth organisms, and would be VERY interesting scientifically.
Some might argue well worth the lives of a few B-list actors...
Michael Miles (film director)
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LXD-75 w/
Stellarvue 102ED
Hardin 10" Newt
Antares 8" Newt
Meade AR-5
Meade N-6
Celestron 102mm refractor
Canon 300D, Meade DSI guiding
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randtek
Under the radar
Reged: 06/18/05
Posts: 1153
Loc: Central Indiana
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[quote. . . Or a similar idea, detecting eye movements to automatically center the scope on the part of the image that is drawing our attention. This would make guiding and exploring an entirely intuitive process.
Sounds like a cool idea, although it would probably make using averted vision a little tough!
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Randy
Gravity: It's not just a good idea, its the law!
ˇʎɐqǝ uo pɹɐoqʎǝʞ ɐ ʎnq ı ǝɯıʇ ʇsɐן ǝɥʇ sı sıɥʇ 
SkyQuest XT10
Homebuilt Surplus Shed 102mm f8.8 refractor
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refractory
Pooh-Bah
Reged: 02/05/05
Posts: 1263
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Awful hard to tie in Sci-Fi movie aliens to ATMing, BUT there WAS that alien navigator in the derelict spaceship, looking like he was GROWN into the chair. Was what looked like his telescope also grown?
THAT would be a revolution (ATM via ATP....?).
Jess Tauber
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gatorengineer
scholastic sledgehammer
Reged: 02/28/05
Posts: 915
Loc: Hellertown, PA
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I think this one is a softball so lets hit it.
Chinese Cellular Mirror blanks. Lets say a 20 inch blank for $500, that weighs 25 lbs.... And GSO sells a finished mirror for $1800....
After that it will be the version of the atlas with Harmonic drives, like the chronos mount, made in china carries 125 lbs for $2k....
--------------------
20" F5 Dob
16" Dob in pieces
Meade SN 6 F3.6 with MPCC ---
12" Doc Clay Sky Patrol MEADE SCT
12.5" F4 Newt under construction
Siebert 45mm Binoviewers
Lots of binos---
Optics Past - MN-71, Comet Catcher, 8" Stf Mak, 4" B&W triplet, 6"Schmidt newt, 12"LX200, C8, Meade LX10-10", 10" MEADE ACF, SN8, TAL150K, Orion 150MC, Jason 60mm refractor, ATM 6" F8, WO 110FLT, 92mm Off Axis Newt, Televue Genesis, Nikon 20x120 bino's, 15x110 Boarderguards, Kuhne Flaks
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kfrederick
scholastic sledgehammer
Reged: 02/01/08
Posts: 783
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i think it would be cool if people started to make there own optics like in the old days and mirror grinding clubs would start up/ that i what atm i about/ not buying a cheep mirror from over seas and puting it in a tube / grinding a mirror is a lot of fun and if there was a nearby club for help you could have even more fun/ it i great when you use a mirror you made and it works good kevin
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Crab
super member
Reged: 02/23/05
Posts: 111
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Revolution makes me think of a large number of people participating. So I assume that any revolution will involve some simplification and lower cost for the same or better utility.
Strangely enough one possible revolution may be Mel Bartel's scopedrive which has been around for years. I believe that scopedrive has been limited by the requirement of two computers and large full circumference bearings. Combine a small cheap low wattage Intel Atom board with a bluetooth handheld and you now have a compact and affordable electronics package.
Edit to add that the intel board would be headless with no keyboard. Scopedrive would be configured to startup at boot. Mini-itx boards are about 7 inches square and Mel bartel's board is similar in size so this part of the package could be contained within an 8x8x4 inch box attached to the mount. If Intel does a nano sized board then the package could be smaller as there is already a more compact design of Mel's controller board available.
Replace the full circumference bearings with sectors moved by screw driven blocks and you now have an affordable solution that is geared down to the point where stepper vibration is easily controlled. This would require a slip clutch and encoders. Such a mount concept would be a hybrid push-to/go-to. You would push the scope close to the target then activate the go-to so the motors do the fine positioning and tracking. Stiction wouldn't matter this way. It could serve reflectors,refractors and cats. Not as simple as a dob but simpler than an equatorial with flexibility and lower cost for the utility.
Edited by Crab (08/18/08 11:38 AM)
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George N
scholastic sledgehammer
Reged: 05/19/06
Posts: 777
Loc: Binghamton & Indian Lake NY
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Quote:
[quote. . . Or a similar idea, detecting eye movements to automatically center the scope on the part of the image that is drawing our attention. This would make guiding and exploring an entirely intuitive process.
Sounds like a cool idea, although it would probably make using averted vision a little tough!
That’s how the targeting system in the Apache attack helicopter works. The gun points were ever the gunner is looking. The computer system even predicts where the gunner is likely to stop his/her eye movement. If you try and make something similar you will probably get visits from Homeland Security and a bunch of patent infringement law suits.
--------------------
George N
Obsession 20
Optical Guidance Systems 10" F/9 R-C Cass
6" F/5 & 8" F/8 home-made Newts
MI-250 mount
SBIG STL-1301E CCD
Member, International Dark-Sky Association
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jdownie
scholastic sledgehammer
Reged: 02/24/06
Posts: 910
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In general, patents are not an issue for the ATM.
John
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ATM project - a terrible waste of good Pyrex.
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mark cowan
Vendor (Obsidian Optics)
Reged: 06/03/05
Posts: 2316
Loc: salem, OR
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Quote:
Strangely enough one possible revolution may be Mel Bartel's scopedrive which has been around for years. I believe that scopedrive has been limited by the requirement of two computers and large full circumference bearings. Combine a small cheap low wattage Intel Atom board with a bluetooth handheld and you now have a compact and affordable electronics package.
In a nod to cheep ATMing let me point out that that software runs on the ubiquitous $20 laptop (n86 where n is 4 or less) under DOS and requires a parallel port to output the timing signals for the steppers to simple transistor circuitry to drive the 2 or 3 steppers (also handles field derotation).
Ie, one obsolete computer and a handful of parts...
Best,
Mark
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Crab
super member
Reged: 02/23/05
Posts: 111
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My apologies, I was confused by discussions of using a dedicated dos box to control the motors. It does only require one. Using two is a good idea though as it frees you from worry about timing issues when using operating systems newer than dos in order to run more capable planetarium programs.
Old laptops are cheap but their running cost can be high as a laptop draws more juice than some newer boards. I believe that Mel Bartels recommends more than a 486 nowadays when microstepping. Here's a link to the type of board I'm discussing.
http://store.microcom.us/alix1c.html
Run it headless with the software in ramdrive and it is very low power draw. Add that the use of sectors eliminates slewing and the battery requirements drop from that as well. There is already interest in controlling a Bartelized scope using a bluetooth enabled cellphone though I don't know if any progress has been made.
My hope is that the progress in low power computing will lead to the crossing of a threshold where a bartels solution is attractive to large numbers of people. I believe that full circumference bearings will have to be abandoned for this to happen as full bearings involve satisfying a number of requirements which turns out to be somewhat complicated. Sectors may seem more complex but they have the potential to simplify things significantly.
I don't like the idea of using a laptop in the field and this is probably a deterrent to others as well.
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Crab
super member
Reged: 02/23/05
Posts: 111
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In case it isn't obvious the solution that may come about would have all boards and batteries on the scope with no wires off the scope. Scopedrive can also control an electronic focuser so it would be all controls except slewing through a bluetooth handheld.
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mark cowan
Vendor (Obsidian Optics)
Reged: 06/03/05
Posts: 2316
Loc: salem, OR
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Whoa, there are operating systems newer than DOS?  Cheap laptop = nearly disposable. The computing load is very minimal, certainly 586s are everywhere. I see your point though. I'd rather have the main power load be for the motors.
IIRC there's a Linux port available as well, the main requirement is that you have a real-time OS, though there are ways to sort of get mostly around such timing issues in Windows, almost.
In any case, of course you can use different controllers and that wouldn't be a bad thing. My preference for goto/tracking systems includes a planetarium as well. What Mel's system does (I've read the code) is implement the motor phasing control in software and thus allow direct driving of the steppers (with that transistor interface I mentioned).
I'm sorry but I don't what you mean by "full circumference bearings." I agree that all the electronics save the bluetooth I/F can be scope mounted. No reason not to have slewing though. Seeing a full driven scope in action while meandering along a planetarium display is insanely fun.
Best,
Mark
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Crab
super member
Reged: 02/23/05
Posts: 111
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when I looked into bartelizing a scope it would have required gearing the motor down in order to have the recommended amount of motion while tracking if using a roller drive. This is why people are interested in worm gears. When a worm gear is used then slewing is slow. If the scope I was considering was twice as large then roller bearings would have worked within Mel Bartels recommendations. The solution I arrived at was to use sectors and hand slew. I haven't implemented that solution as I have been waiting for low power computers as a laptop in the field is a showstopper for me. So the incentive for using sectors instead of a full circumference drive is that the need for speed while slewing combined with the need for very fine steps while tracking is difficult to satisfy with a roller based drive mechanism when applied to smaller scopes.
When mentioning a full circumference solution I'm talking about the azimuth. The alt is less than a full circle of course.
The board linked above draws between 4 and 5 watts, storage draw included. I haven't found a cheap laptop that gets close to this. Some laptops have built in power saving features that interfere with scopedrive. If you toss your laptop and replace it with a different model then you may have to re-time everything.
Motored slewing if great but one with sectors and hand slewing should make timing the microstepping a forgiving process. Buying a cheap board is simpler than buying a used laptop where documentation may be sparse and everything may not work. The battery most likely won't.
There is a reason that the majority of people haven't bartelized their scopes.Maybe what I'm talking about won't happen but I believe that any revolution will be a down to earth nuts and bolts sort of thing.
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mark cowan
Vendor (Obsidian Optics)
Reged: 06/03/05
Posts: 2316
Loc: salem, OR
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Quote:
There is a reason that the majority of people haven't bartelized their scopes.
Yes there is, it's not simple! To do it right it's best if you designed it that way from the beginning, the balance and particularly the bearings - as you need roller bearings in place of teflon to make it work.
Quote:
When mentioning a full circumference solution I'm talking about the azimuth. The alt is less than a full circle of course.
How does that relate to what you're talking about, though? Sector (worm) drives are just another way of coupling the motor to the axis. Slewing speed with a roller drive and encoders on both axis shouldn't matter as you just hand slew and let it fine tune the position as needed. Microstepping on rollers with gear reduction should suit any size you cared to motorize...
Best,
Mark
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kfrederick
scholastic sledgehammer
Reged: 02/01/08
Posts: 783
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i think the telescopes in the years to come are going to be bigger faster with thiner mirrors
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