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Equipment Discussions >> ATM, Optics and DIY Forum

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kfrederick
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Why no CHiefs intrest???
      #5597500 - 12/31/12 08:10 AM

So all you experts Here is your question .Why no interest in the Ed Jones Chief design ? I have said about how easy to have a unobstructed large telescope with two small lens. No pro interested .Ed is not building any that I know of . Mike did a design for me but does not seem excited So what is wrong here .I have two A 20 f8 and a 17 f9 . My 17 has some improvements that helpes it sets up fast and works Great . I am a Amateur I do not know optical like these .So why no one interested in a much better way . I could care less what any one uses and am not here saying this to be braging .All I am reporting is this works great Easy two lens . Zemax says my 17 should work unreal

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cheapersleeper
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Re: Why no CHiefs intrest??? new [Re: kfrederick]
      #5597550 - 12/31/12 09:03 AM

I am under the impression that the tolerances for placement of the correcting lenses is critical to the point that I would not be able to construct a structure that would allow initial alignment and then hold that alignment.

Regards,
Brad


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kfrederick
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Re: Why no CHiefs intrest??? new [Re: cheapersleeper]
      #5597576 - 12/31/12 09:23 AM Attachment (47 downloads)

Correct the placement of the secondary and lens and focuser and laser target is in one box .The math is crazy hard and I had no clue . Dave O work can not be under stated . He saved my project .

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cheapersleeper
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Re: Why no CHiefs intrest??? new [Re: kfrederick]
      #5597582 - 12/31/12 09:29 AM

If your project, with your experience, needed "saving," then it's not for me.

B


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NHRob
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Re: Why no CHiefs intrest??? new [Re: cheapersleeper]
      #5597733 - 12/31/12 11:04 AM

I have been interested but, would prefer a focal ratio of < f/8. It seems that this would require custom corrector lenses.

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careysub
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Re: Why no CHiefs intrest??? new [Re: kfrederick]
      #5597740 - 12/31/12 11:08 AM

Quote:

So all you experts Here is your question. Why no interest in the Ed Jones Chief design ?




Doesn't Ed have a book on this is the works?

I am interested, but am waiting for his book, so that I can take the full benefit of his insights and designs. (I hope this will encourage Ed in his book project, here is a guaranteed sale.)

(And in the meantime have other, more elementary, projects I have not gotten to yet.)


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jgraham
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Re: Why no CHiefs intrest??? new [Re: careysub]
      #5597779 - 12/31/12 11:30 AM

"I have said about how easy to have a unobstructed large telescope with two small lens."

Hmmmm, I usually can't use 'lenses' and 'easy' in the same sentence, particularly if those lenses need to be tilted and aligned to an optical axis without clear reference points. It is a neat design, but beyond what I can do with the simple tools I have.


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Ed Jones
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Re: Why no CHiefs intrest??? new [Re: cheapersleeper]
      #5597944 - 12/31/12 01:07 PM

There are several ATMs I know of working on Chiefs. It isn't necessary to make a CNC machined housing. I've built all mine with a drill press and hand tools, they are posted on the spiderless group. There aren't many ATM lens makers and the larger size Chiefs need custom lenses. However there are some Chief designs under 10 inches that can use off-the-shelf lenses.

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NHRob
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Re: Why no CHiefs intrest??? new [Re: Ed Jones]
      #5597971 - 12/31/12 01:28 PM

Ed,
I was thinking of an 8" Chief. Could an f/8 or faster Chief be made with off-the-shelf lenses?
Rob


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Mike I. Jones
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Re: Why no CHiefs intrest??? new [Re: NHRob]
      #5598351 - 12/31/12 04:54 PM

Kevin slightly misinterpreted me on Chiefs. I was happy to do his apochromatic Chief design, tolerancing and 3D plots for his machinist, and excited to hear about how good the finished telescope worked. But it's not on my personal bucket list. I have a 10" f/27 Maksutov, 8" Rosin astrograph and 8" apochromatic triplet and new kind of scope to do first. If I have any energy left after those, I want to do an 8" Herrig, maybe a big Schupmann, and 24" modified Dall-Kirkham, then I'll probably quit and just enjoy the scopes.
Mike


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Ed Jones
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Re: Why no CHiefs intrest??? new [Re: NHRob]
      #5598429 - 12/31/12 05:32 PM

Rob,
Actually I think so. I haven't worked a design yet but I found a lens combination in my latest Zemax catalog (or else I just missed it before) that might work for an 8 inch F/8 maybe F/7. Stay tuned, I post it on spiderless.


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NHRob
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Re: Why no CHiefs intrest??? new [Re: Ed Jones]
      #5598488 - 12/31/12 06:12 PM

Hi Ed,

Great. I'll look there.

Thx.


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kfrederick
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Re: Why no CHiefs intrest??? new [Re: NHRob]
      #5598663 - 12/31/12 08:01 PM

Not sure why we cheer on New Years .Another year gone .Any way Happy loss of another year.Bucket list telescopes would be a good post . I have mine.

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MKV
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Reged: 01/20/11

Re: Why no CHiefs intrest??? new [Re: kfrederick]
      #5598707 - 12/31/12 08:27 PM

Quote:

Not sure why we cheer on New Years .Another year gone .Any way Happy loss of another year.Bucket list telescopes would be a good post . I have mine.



K, every day is a New Year gone by. Something to think about.

Mladen


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Mark Harry
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Re: Why no CHiefs intrest??? new [Re: Mike I. Jones]
      #5599214 - 01/01/13 08:58 AM

Just because you have a new observatory, doesn't mean you have to fill it!
M.


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kfrederick
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Re: Why no CHiefs intrest??? new [Re: MKV]
      #5599238 - 01/01/13 09:14 AM

The intent of this post was to get some ideas why the big boys are not all over this . And to state there are NO problems with this design . Dave O did a great paper explaining a 10 inch I hope he will post it . This is not about People or telescopes .It is about the design and all the ways it can be done .

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polaraligned
professor emeritus


Reged: 12/26/08

Re: Why no CHiefs intrest??? new [Re: kfrederick]
      #5599267 - 01/01/13 09:41 AM

At the focal ratios you are talking about, the CO should be a moot point. So what is to be gained? Seems an optimized Newt would be a lot easier to build and perform just as well.

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Mike I. Jones
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Re: Why no CHiefs intrest??? new [Re: polaraligned]
      #5599359 - 01/01/13 10:52 AM

There are definite advantages to a Chief, some of which can be borrowed from Ed Turco's recent thread on optimized Newts vs. Apos:
1. Eyepiece is located farther down the tube and more convenient.
2. Less of the light path crosses through itself, thus reducing in-tube convection effects. The path from the primary to the secondary shares part of the path of the incoming parallel light, and an even smaller portion is common between the primary and secondary path, and the secondary to L1.
3. The cost for the two small corrector lenses is less than a full-aperture 1/20 wave optical window for a 17" to 20" optimized Newt.
4. Ghost reflections are essentially absent, as all optics are operated off-axis.
5. Commercial lenses can be used for smaller instruments, further reducing cost.

The disadvantages of a Chief that I see limiting or prohibiting it from commercial interest are:
1. Alignment sensitivity
2. Structural stiffness required to maintain alignment over all pointing angles from near-horizon to zenith.
3. A required skill level in collimation that may not be present in beginning telescope owners, who can barely keep a Newt properly aligned if at all.
4. Requires an Amici or pentaprism to give an image without reversion. By itself, the Chief optical system acts similar to a Cassegrain with an off-center pupil, and gives an inverted image. Using a fold mirror or prism flips the image across one axis, but not the other. It would take a pair of reflections from a pentaprism or pentamirror to restore the image to simple inversion. The Amici prism would give an erect image without inversion.
5. Cost versus benefit/sales volume - Can Chiefs really be commercially made at any useful sales volume or profit margin? Kevin's Chief has set the bar in Chief size and quality that may never be beaten. But could he make an order of, say, 250 units, and make anything like a profit? I would estimate no, it would not be a profitable commercial product.

The Chief does work, and is an admirable project for advanced ATM's like Ed and Kevin, but I'm not seeing it as attractive to a commercial dealer wanting to make a 10% profit margin. I also see it as very intensive post-sale support in trying to work with customers to align their scopes. I could also be completely full of it, and there might be mass-production techniques that haven't been developed yet that could actually give a 10% profit and reasonable cost and delivery.

Mike


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Jeff Morgan
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Re: Why no CHiefs intrest??? new [Re: kfrederick]
      #5599361 - 01/01/13 10:54 AM

Quote:

So all you experts Here is your question .Why no interest in the Ed Jones Chief design ?




Firstly, the premise of your question may not be valid. Adoption of new ideas in telescopes takes some time. Cases in point: Roland Christen was publishing designs and building apochromatic refractors in the early 1980's, yet the scopes did not become wildly popular until late in that decade. IIRC, even into the (very) early 1990's the "wait list" for one of his scopes was barely longer than the fabrication time. Another case in point: John Dobson was building and showing his alt/az Newtonians in the late 1970's. The earliest reference I could find of one appearing at a star party was either 1979 or 1980 Riverside (I can't recall the exact year off the top of my head) where he won a 1st prize award. His scope was (technically) a very small leap yet manufacturers (and amateurs) didn't adopt it in numbers until much later in the 1980's.

I prize the performance of long focus mirrors, and think the Chief would be great. I am very tempted. But I haven't done one yet. Looking at the Chief deign specifically, here is what I see:

1) Every design appears to be "custom". Not only does one have to take into account aperture and focal ratio (like a Newt), but the angles may be different depending upon the ideas of the builder, and the lens prescriptions and tilts change. Very few amateurs today grind their own mirrors, and amateur lens makers could probably be counted on two hands. Meanwhile, in a Newtonian a flat is always a flat, and widely available.

2) To derive these solutions, one must have optical design software. Not only is software cost a hurdle, but I would question my own ability to understand it and derive valid data from it. Not being an optician, I would fear being nothing more than a chimp banging on on a piano. It would not be a happy day to finish a $1,000+ project only to learn it was fatally flawed from the drawing board.

3) I am in the minority in my appreciation for long-focus mirrors. As such, I have a 16" f/7 "laying around" that could be re-purposed. Or, I would seriously consider spending money (or time) to acquire a more suitable one. Most astronomers today have (or want) short mirrors that would be unsuitable to the project.

4) The fabrication challenges probably deter many. I have built many scopes and enjoy working with wood, but even so my shop is relatively simple. And I have no metal working capability or experience beyond a hacksaw, drill press, and a couple of thread taps. Any metal components or optical carriers would have to be farmed out to a custom machinist. Certainly easy to find, but not low-cost.


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kfrederick
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Re: Why no CHiefs intrest??? new [Re: Jeff Morgan]
      #5599468 - 01/01/13 12:10 PM

The key to why a CHief can be very easy to line up .Is EDs way of reflecting the laser off the two mirrors Because it is a large distance . You can set this tilt fast and perfect . Stiffness yes it is needed but very easy to check for flex . The laser needs to be centered on the primary move the telescope and see if it stays there . As for ATM project perfect .proven .So thankfull for the replys

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MKV
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Re: Why no CHiefs intrest??? new [Re: Mike I. Jones]
      #5599597 - 01/01/13 01:13 PM

Quote:

Less of the light path crosses through itself, thus reducing in-tube convection effects



On a different thread (the Herrig) the light crosses its own path three times, but convection effects were never mentioned, IIRC. How damaging are such effects?

Mladen


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Mike I. Jones
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Re: Why no CHiefs intrest??? new [Re: MKV]
      #5599625 - 01/01/13 01:29 PM

Th mutual paths are a lot shorter than for a Newt. I'll let you know when I build my 8" Herrig.

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Ed Jones
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Re: Why no CHiefs intrest??? new [Re: Mike I. Jones]
      #5599806 - 01/01/13 03:17 PM

I agree with you Mike except that I don't find alignment much of a problem. It is a learned skill needing instruction but I can use a simple laser and get dependable results. That's not true with a fast Newt where you need a barlowed laser, a simple laser just isn't accurate enough. Slower systems usually have looser tolerances.

If there is enough demand for a product people want someone will produce it.


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kfrederick
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Re: Why no CHiefs intrest??? new [Re: Ed Jones]
      #5599825 - 01/01/13 03:28 PM

+1

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MKV
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Re: Why no CHiefs intrest??? new [Re: Mike I. Jones]
      #5599829 - 01/01/13 03:30 PM

Quote:

Th mutual paths are a lot shorter than for a Newt. I'll let you know when I build my 8" Herrig.



Yes, Mike, the paths are shorter but there are more of them in this case. I was hoping you could direct me to a study done on the effects of path crossing, rather than tell me to wait for your to build the Herrig - given that the Herrig is last on your bucket list! Gee, then, I guess neither one of us knows how bad this path crossing is, do we? I'll look elsewhere. Thanks.

Mladen


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kfrederick
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Re: Why no CHiefs intrest??? new [Re: MKV]
      #5600174 - 01/01/13 07:18 PM Attachment (20 downloads)

Corrector data Mike work

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kfrederick
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Re: Why no CHiefs intrest??? new [Re: kfrederick]
      #5600188 - 01/01/13 07:26 PM Attachment (34 downloads)

Primary data

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Dave O
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Re: Why no CHiefs intrest??? new [Re: kfrederick]
      #5600328 - 01/01/13 09:01 PM

Quote:

Dave O did a great paper explaining a 10 inch I hope he will post it .




That little document was created for Jack S, and is specific to his CHief; he has added some more information from an actual construction point-of-view (again specific to his design). As far as I am concerned, it is his document now, and he is free to do with it as he likes.


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StarryHost
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Re: Why no CHiefs intrest??? new [Re: Dave O]
      #5600466 - 01/01/13 10:29 PM

Ooops! I just saw this thread. I will dig up the document and publish tonight if I can. The combined effort of several people is represented in it and it should encourage the art of the CHief.

As for me, I've got my long focus Newt now and it's just massive. The CHief is still attractive for me and now that I have my newt, I can go back to stabilizing the problems I had with the mount and CHief's upper OTA.

Kevin's concept of the waterjet upper OTA is I think really good for those of us who are intimidated by field collimation. Ed assures us that the skill is learnable and not necessary every single time, but I am cautious.

I'll post the document in a bit.

Thanks,
Jack Swaton
www.StarryHost.com


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StarryHost
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Re: Why no CHiefs intrest??? new [Re: StarryHost]
      #5600488 - 01/01/13 10:43 PM

OK. Here is The Document...but it is too big to post.

If you want a copy, please email me at jack.swaton@starryhost.com. :-)

This document has contributions by Dave and Mike and Kevin. The document is part narrative and part compilation of emails.

I don't have the time to clean it up anymore right now, but I am saving it for my assured return to the CHief.

Enjoy. If you have questions, I will do my best to answer.

Ed,
If you have feedback for this doc, please by all means let me know.

Best,
Jack Swaton
www.StarryHost.com


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Mike I. Jones
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Re: Why no CHiefs intrest??? new [Re: StarryHost]
      #5600491 - 01/01/13 10:46 PM

Jack,
Could you email it to my Yahoo account?
Thanks,
Mike


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StarryHost
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Re: Why no CHiefs intrest??? new [Re: Mike I. Jones]
      #5600495 - 01/01/13 10:52 PM

Done! The email is winging it's way through cyber space even as we speak.

Jack


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mark cowan
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Re: Why no CHiefs intrest??? new [Re: Mike I. Jones]
      #5600584 - 01/02/13 12:26 AM

Quote:

5. Cost versus benefit/sales volume - Can Chiefs really be commercially made at any useful sales volume or profit margin? Kevin's Chief has set the bar in Chief size and quality that may never be beaten. But could he make an order of, say, 250 units, and make anything like a profit? I would estimate no, it would not be a profitable commercial product.




I'll address that, while noting that yes, just setting up a Newtonian properly defeats a lot of people.

As a mirror maker, there's mostly one surface (the primary) that I'd make any profit on. The other components are farmed out (certainly in the case of Kevin's 17"). There's just not enough return from a long f/ratio primary, even with hyperboloid correction, to make it worth pursuing. Yes, one for myself, cool, I'd like to have it. Try to make them to sell (optics sets or finished scopes), no way. The user support could indeed be a killer.

CO vs no CO? Definitely I come down on the unobstructed side. But I have my own redesign of the Stevick-Paul on my list that's mountable and all mirrors, something I'm make first at a 14" size. It has the advantage...wait for it...that I fiddled around optimizing a new take on the SP that could be supported in a standard sort of dob structure.

I'd like to see the Traveling Chief Road Show. Set that thing up at OSP next fall and there'll be a LOT of interest. But until the eyes meet the EP it's difficult to commit the units that commercial manufacture would require. This is one for the converts, long standing or newly minted from handy materials...

Kevin has done a great thing in making the lens-box assembly available to anybody at about his cost, I think he's right that this simplifies it to the point of ease. Not sure if he's publicized that very much yet - uhm, or if he really intended that and wasn't just talking to me - though we have discussed it. But the $2.5K or so for the 17" lens set (less in qty) is still a stickler, and ya know those probably really do need to be coated for throughput (not reflections) and that's pricey.

This is not in any particular order. But I'd like to see Kevin talk on about his experiences with this thing because he's the one that's been pushing on with it to see the fulfillment of the no-compromise large unobstructed design that this is.

Best,
Mark


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Mike I. Jones
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Re: Why no CHiefs intrest??? new [Re: mark cowan]
      #5600604 - 01/02/13 12:52 AM

+1 from me on that, Mark!

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dave brock
professor emeritus


Reged: 06/06/08

Loc: Hamilton, New Zealand
Re: Why no CHiefs intrest??? new [Re: kfrederick]
      #5600728 - 01/02/13 04:41 AM

Quote:

Why no interest in the Ed Jones Chief design ?




A question for you Kevin.
Would you have your 20" Chief if you didn't have Ed to make the lenses?

Dave


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kfrederick
Carpal Tunnel
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Reged: 02/01/08

Re: Why no CHiefs intrest??? new [Re: dave brock]
      #5600764 - 01/02/13 06:47 AM

There would be no Chiefs with out EDs work. He showed me how to set them up .. Mike came up with the idea for the hyperbolic chief .And the slotted box set up is mine.

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kfrederick
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Re: Why no CHiefs intrest??? new [Re: kfrederick]
      #5600815 - 01/02/13 07:54 AM

Could a CHief be made using a concave secondary mirror?

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kfrederick
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Re: Why no CHiefs intrest??? new [Re: kfrederick]
      #5600823 - 01/02/13 08:00 AM

http://www.gmto.org/ I wonder if the Chief corrector would help these guys TEST there offaxis mirrors. They said how hard it was to have a test for the outside mirrors .

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Mike I. Jones
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Re: Why no CHiefs intrest??? new [Re: kfrederick]
      #5600929 - 01/02/13 10:11 AM

I think Ed's use of a flat secondary is the easiest. The bend angle after the secondary can be set to any value convenient for observing. Its flat surface removes it from any contributions to system aberrations other than tilt misalignment. I haven't built one, but ZEMAX tolerancing tells me Ed's Chief is simpler to align, and more tolerant to structural flexure as the scope is aimed from horizontal to vertical.

Your 17" Apo-Chief has a long-radius convex secondary, which forces your bend angle to a single value. But combined with the hyperboloidal primary, the convex secondary was what allowed the last bit of correction over your FOV.

Kevin, I think the 17" Apo-Chief you have built is one of the most remarkable achievements in ATM history, right up there with Russ Porter's Springfield mount, TCT's like the Stevick-Paul and Schupmann, the Houghton and Schmidt configurations, and the Dobson mount. I would say its design and fabrication may remain unique in history, even with the other Chiefs being built.

I agree with Mark Cowan that it's well worth taking around the country and showing at major star parties. I don't know when, but I do look forward to viewing through it on some still, quiet night with good seeing and transparency.

Mike


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Mike I. Jones
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Re: Why no CHiefs intrest??? new [Re: StarryHost]
      #5600979 - 01/02/13 10:38 AM

WAAOWW! I had no idea Dave went to that much trouble to document Jack's scope. Outstanding writeup!
Mike


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StarryHost
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Re: Why no CHiefs intrest??? new [Re: Mike I. Jones]
      #5600998 - 01/02/13 10:47 AM

Yes,
He has given a ton to this project in time and expertise as have others. I love the giving nature of the folks in this group.

Jack


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kfrederick
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Re: Why no CHiefs intrest??? new [Re: StarryHost]
      #5601108 - 01/02/13 11:40 AM

This 17 needs a good mount so I can take CCD pic .Think A GEM? . The paper Dave did for Jack 10 inch is great . This design uses off the shelf lens and a flat secondary . Daves and Mike work is great about explaining how to make one .Like I said in the top his work cannot be understated . As well as Mike and ED . I am sure as more people build these can will only get better . Thanks for the kind words .

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Jeff Morgan
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Re: Why no CHiefs intrest??? new [Re: mark cowan]
      #5601480 - 01/02/13 03:55 PM

Quote:


As a mirror maker, there's mostly one surface (the primary) that I'd make any profit on.




OK Mark, here is an idea that seems largely forgotten: The Sasian unobstructed Newtonian as published in Sky & Telescope March 1991?

For those not familiar, it used a tilted 6" f/9 paraboloid. The secondary mirror was ground with a torodial surface and mounted to pass light back across the tube to the focuser. Like the Chief it is unobstructed, but does not result in much (if any) length reduction compared to a standard Newtonian. It generally resembles the DGM off-axis Newtonian, but without the waste inherent in creating the daughter mirrors.

That would give you two pieces of glass fabricate and sell (one of them being very unique), and a layout that would be generally familiar to most users. I would imagine support efforts would be quite reasonable.


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Jim Romanski
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Re: Why no CHiefs intrest??? new [Re: kfrederick]
      #5601501 - 01/02/13 04:05 PM

I've been following these Chief threads with great interest. My Dad gave me an old but essentially unused 12.5" F/8 Upco mirror which is 40+ years old. It's in spectacular condition and probably doesn't even need to be coated. He thinks it has a very good figure too. It would be a great candidate for making a Chief since it has 100" focal length and would otherwise make for a very long standard newt.

My problem is time. I'm still finishing the 17.5" dob that my father-in-law started. Then I have an 8" Cave to do some resoration on. Oh and I really want to rebuild the 13.1" Coulter. So the Chief is last in line and I don't know when I'll get started on it.

I would like to know if I can get off the shelf lenses for the project. I might even go ahead and get them now and layout the design. But it'll be sometime before I actually start building it.


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Ed Jones
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Re: Why no CHiefs intrest??? new [Re: Jim Romanski]
      #5601976 - 01/02/13 09:15 PM

Jim,
Yes it may be possible to make a 12.5 inch F/8 Chief. Ross Optical has a 3 inch diameter negative lens of the right focal length. It can be matched up with a 60 mm convex lens (no one makes a matching 3 inch convex lens). I've never tested any Ross Optical lenses so I don't what quality they make but in theory it works.


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mark cowan
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Re: Why no CHiefs intrest??? new [Re: Jeff Morgan]
      #5602191 - 01/02/13 11:50 PM

Quote:

For those not familiar, it used a tilted 6" f/9 paraboloid.




Just a bit small. An awful lot of unobstructed designs don't scale up well, and really (just my opinion) the interesting ones are the ones that do - SP, CHief, Schupmann, and maybe one other that I can't recall offhand...

Best,
Mark


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sqrlman
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Re: Why no CHiefs intrest??? new [Re: Jeff Morgan]
      #5602448 - 01/03/13 07:24 AM

The Sasian unobstructed Newtonian actually used a F12 primary.
I have the original telescope shown here:
http://bhs.broo.k12.wv.us/homepage/alumni/dstevick/unobnewt.htm
The optics need to be remounted in something less flimsy. If anyone is interested in it send me a PM.

Steve


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kfrederick
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Re: Why no CHiefs intrest??? new [Re: sqrlman]
      #5602540 - 01/03/13 08:46 AM

Steve feel free to talk about the telescope as any others .

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tim53
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Re: Why no CHiefs intrest??? new [Re: sqrlman]
      #5602751 - 01/03/13 11:08 AM

Quote:

The Sasian unobstructed Newtonian actually used a F12 primary.
I have the original telescope shown here:
http://bhs.broo.k12.wv.us/homepage/alumni/dstevick/unobnewt.htm
The optics need to be remounted in something less flimsy. If anyone is interested in it send me a PM.

Steve




I remember that scope and article. That would be splendid on a Springfield mounting.

-Tim.


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kfrederick
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Re: Why no CHiefs intrest??? new [Re: tim53]
      #5604605 - 01/04/13 11:33 AM

This will work best is in large sizes the bigger telescope has more HP The improvement can only happen if everything is 100% . Why bother to make one 90% . Go with the hyperbolic primary/ curved secondary and the APO lens then the CHief could be a HDT High Def Telescope . By far the most important part is the primary and having Carl do that was a good move . This can only get better.. Mikes numbers are great . So glad he is here on cloudy nights .

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ed_turco
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Re: Why no CHiefs intrest??? new [Re: kfrederick]
      #5604672 - 01/04/13 12:17 PM

Seems like everyone forgot that Jose Sasian also created a Yolo-like setup with two concave mirrors. He even provided a computer program to assess just about any system. As I remember a 6" Sasian system f/10 I assessed and found this to be as good as a 6" f/10 Newt. And, this system scaled up nicely.

But none of youse guys, (just kidding) would know what to do with an executable DOS program, would you?

By the way, Jose Sasian has a PhD after his name for precisely his work in creating these systems. Quite the man; he kindly talked to me on numerous occasions, though I never built this system.


ed_turco


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MKV
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Re: Why no CHiefs intrest??? new [Re: ed_turco]
      #5604687 - 01/04/13 12:27 PM

Ed, I wrote my own raytrace and optical analysis program in the 1981 on Sharp PC1500 in BASIC and compiled it with on an IBM AT. I also programmed my Epson dot matrix printer for my own proportional width fonts and scientific symbols in BASIC, along with full justification and proportional spacing printing commands. Almost everything people do with spreadsheets today I did with BASIC for many subroutines.Some of us still know what to do with an executable BASIC file.

Mladen


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kfrederick
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Re: Why no CHiefs intrest??? new [Re: ed_turco]
      #5604697 - 01/04/13 12:33 PM

Ed if you have the program feel free to post it .Or any other designs .They are all cool and worth optimizing . Tall order topping a great newt . But a newt has been optimized . Mike was talking about a Hamintonian yolo . A warped Hchericalian with a CCD would be great one surface . And the ccd could go any place . They have one CCD camera that downloads a 8.5 meg pic every second . No eyepiece needed . or ladder or be in the cold .

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tim53
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Re: Why no CHiefs intrest??? new [Re: kfrederick]
      #5604752 - 01/04/13 01:03 PM

Putting a ccd camera at the prime focus of a Newt primary is something I've been wanting to do for a long time. This will work for larger apertures better than smaller ones because the camera doesn't scale up with the aperture, so the CO - if you use a parabolic primary - gets relatively smaller as the aperture increases. The practical upper size limit of such a "camera" system might only be limited by the length of cabling you need to plug the camera in. No more ladders! And if you put another camera at the focus of a finder and a guidescope, no more eyepieces!

I like the machine vision cameras because many of them are very small (Pt Grey fleas are about 1 1/4" cubes. Depending on the camera, you could get up to about 6 megapixel mono or RGB 16-bit digital video at 15fps or so, up to 60 minutes/frame. Only thing they lack is cooling, but you wouldn't need to cool a planetary monitoring camera (like watching for impacts on Jupiter).

-Tim.


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Startraffic
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Reged: 02/12/06

Loc: Lat. 39.143345, Long. -77.1748...
Re: Why no CHiefs intrest??? new [Re: kfrederick]
      #5604794 - 01/04/13 01:24 PM

kfrederick,
I wouldn't say no interest. I have plans under development for a 14.5" f30 Schiefspiegler binoscope on a 16ft trailer observatory. A kissin' cousin of a CHief I believe. The math does hurt my head & I haven't even finished the mirror designs yet. I have the trailer though.

Clear Dark Skies
Startraffic
39.138274 -77.168898

Edited by Startraffic (01/04/13 01:45 PM)


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audioaficionado
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Loc: Medford, Orygun, USA
Re: Why no CHiefs intrest??? new [Re: Startraffic]
      #6036677 - 08/20/13 02:45 PM

Very fascinating ATM you've built Kevin. I'm interested in the concept, but I don't think I could do an ATM anytime soon. This doesn't look like a good first project since I don't have access to a decent workshop. I don't think my 10x12 garden shed would cut it lol.

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Pinbout
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Re: Why no CHiefs intrest??? new [Re: audioaficionado]
      #6036705 - 08/20/13 03:03 PM

that is really no excuse.

I have no shed, I have nothing but metal frame with rotting birch ply that's been outside for 3years, time to replace finally

check it out in this vid. I've built 5-6 scope on it, ok I have another foldable table that helps out while painting...

http://www.youtube.com/watch?v=i43O2BGj0-s


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