Raven911
Carpal Tunnel
Reged: 03/12/05
Posts: 1815
Loc: by Cloudcroft, NM
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It is actually a bit of a vendetta of mine to produce good images using gear that is either obsolete or not what is normally used. Just to show it can be done with things other than a $10,000 dollar mount and $5000 dollar scope.
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http://smg.photobucket.com/albums/v287/Raven911/Astrophotos/
http://www.eye-of-the-raven.blogspot.com/
My list of second-hand and home-made stuff:
Celestron SC6
Celestron C9.25
100mm F6/76mm F4.5/80mm F5/SV NHII 80mm F6 Achros
SBIG ST7/Canon 300D/DSI Pro Mono/Starshoot DSCI
8 inch F7 Newt on Edmund EQ
8 inch F4.5 Project Astrograph
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old_frankland
professor emeritus
Reged: 03/28/05
Posts: 525
Loc: San Francisco Bay Area
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If you simply gotta do color, then I guess you gotta do color. But, if you're interested in seeing and imaging what is out there, especially with modest equipment, don't be so quick to toss imaging in monochrome. Narrow band specifically.
http://www.lafterhall.com/atk16_ic410.html
http://www.lafterhall.com/atk16_b33.html
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Cheers,
Jim
Livermore CA
http://www.lafterhall.com/astro.html
3" APO, 4" ED refractor, 9" SCT, GM8
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revans
Carpal Tunnel
Reged: 09/26/05
Posts: 1517
Loc: Fitchburg, MA
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Its not that I'm at all against narrow band imaging in monochrome with H-alpha... its just that my preliminary attempts just using an LPR filter made me believe that the imaging time was increased exponentially by the addition of the filter... that's the only thing holding me back... because I can't do much more than 30 minutes exposure time right now... but by next summer hopefully longer exposures might be possible... I think your monochromes are top notch... I haven't seen better anywhere...
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Rick Evans
http://www.freewebs.com/revans_01420/
"The universe is there for us to see, but it cannot be understood without learning its language -- mathematics." Galileo Galilei
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old_frankland
professor emeritus
Reged: 03/28/05
Posts: 525
Loc: San Francisco Bay Area
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I typically work with 10 to 20 minute guided exposures when shooting H-alpha and OIII. Frankly, too much can go wrong with a portable setup doing 30+ minute exposures. You lose one of those to a plane passing through, a mount drive hic-up or a bump to the tube, that's a lot of thrown away imaging time. Losing a 10 or 15 minute exposure doesn't hurt so bad.
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Cheers,
Jim
Livermore CA
http://www.lafterhall.com/astro.html
3" APO, 4" ED refractor, 9" SCT, GM8
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revans
Carpal Tunnel
Reged: 09/26/05
Posts: 1517
Loc: Fitchburg, MA
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OK.. but when I say 30 minute exposure what I really mean is ten exposures of 3 minutes each, unguided... doing more than that unguided can drive you crazy 
Rick
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Rick Evans
http://www.freewebs.com/revans_01420/
"The universe is there for us to see, but it cannot be understood without learning its language -- mathematics." Galileo Galilei
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old_frankland
professor emeritus
Reged: 03/28/05
Posts: 525
Loc: San Francisco Bay Area
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Oh, well, that's a horse of a different color.
This one was manually guided, as was B33.
http://www.lafterhall.com/atk16_ngc2264.html
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Cheers,
Jim
Livermore CA
http://www.lafterhall.com/astro.html
3" APO, 4" ED refractor, 9" SCT, GM8
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revans
Carpal Tunnel
Reged: 09/26/05
Posts: 1517
Loc: Fitchburg, MA
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Nice ! It inspires me to get my SXV-7m up and running again as an autoguider. I'm probably not that far from getting everything to work again. I had it working on my Tak EM-200 mount but the short tube refractor can only be mounted on my G11... and so I have to transition the autoguider to a "new" mount. I think it should work OK.. but haven't put much time into it yet... have to connect through the GPUSB box, get MAXIM DL to recognize the camera and mount combo etc... most likely the project will wait until next summer though... until then I'll probably stay unguided or maybe manually guided... unless I find some ambition...
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Rick Evans
http://www.freewebs.com/revans_01420/
"The universe is there for us to see, but it cannot be understood without learning its language -- mathematics." Galileo Galilei
Edited by revans (10/29/09 06:33 PM)
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old_frankland
professor emeritus
Reged: 03/28/05
Posts: 525
Loc: San Francisco Bay Area
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So many cool things to do, so little....well, you know.
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Cheers,
Jim
Livermore CA
http://www.lafterhall.com/astro.html
3" APO, 4" ED refractor, 9" SCT, GM8
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RogerRZ
Whatta you lookin' at?
Reged: 01/09/06
Posts: 2584
Loc: West Collette, NB, Canada
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I would invite those who would like to do photography and think an apo is unaffordable to take a look at a used 80ED. Often seen for sale at less than $300, this will yield pinpoint stars without the need for processing.
It won't pull in as much light for visual use as a 120mm scope, but with a little longer exposure, you will get roughly the same image scale as the bigger scope, and will absolutely lay waste to any this or any achro. This is just my opinion, of course, but I would invite anyone who questions this to do a quick Google search on 80ED+M27 and see what turns up...
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-Roger Pitre-
1 X 7 binocular Astro-Tech Imaging Newtonian MPCC
Starblast guidescope Starshoot autoguider
EQ6 Pro, HEQ5, Canon 50D, 70-200 f/4L
"He's got shoulders on him like a smelt..."--Anonymous
http://www.facebook.com/album.php?aid=10723&id=509325956&l=79d06a1d10
http://ajpobservatory.isgreat.org/
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revans
Carpal Tunnel
Reged: 09/26/05
Posts: 1517
Loc: Fitchburg, MA
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I don't disagree, but I hate to give up the extra aperture as I'd ideally like to image things fainter than M27... I think 120 mm is just about right for what I'd like to do in time... if I'm not successful with narrowband with the achro (and that will take a long time for me to achieve since I don't like to be out there experimenting in the freezing cold of a New England winter surrounded by deep ice and snow... only have enough energy for "sure things" under those conditions.. but hopefully it can be next a next spring or summer project for me). If all else fails then my next target scope would probably be the EON 120 but I may not see one of those for a couple of years... which gives me plenty of time to learn AP... and get my autoguider setup working...
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Rick Evans
http://www.freewebs.com/revans_01420/
"The universe is there for us to see, but it cannot be understood without learning its language -- mathematics." Galileo Galilei
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Raven911
Carpal Tunnel
Reged: 03/12/05
Posts: 1815
Loc: by Cloudcroft, NM
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Too many pics out there from 80ed's. Great little scope, but way too popular. I have had several chances to do this very thing, but went the 6" sct route instead for the extra aperture and the fact that images from them are exceedingly rare. I have an 80mm Stellarvue, but it mostly sees guidescope duty.
Now some flavor of large triplet would perk my interest, but I would probably have to sell one of my children to buy it. There are cheaper knock offs out there (like Orion) but they just don't get me real excited for some reason.
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http://smg.photobucket.com/albums/v287/Raven911/Astrophotos/
http://www.eye-of-the-raven.blogspot.com/
My list of second-hand and home-made stuff:
Celestron SC6
Celestron C9.25
100mm F6/76mm F4.5/80mm F5/SV NHII 80mm F6 Achros
SBIG ST7/Canon 300D/DSI Pro Mono/Starshoot DSCI
8 inch F7 Newt on Edmund EQ
8 inch F4.5 Project Astrograph
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snart
professor emeritus
Reged: 04/07/05
Posts: 596
Loc: Cincinnati, OH
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Quote:
Too many pics out there from 80ed's.
And let's just think why this is? Or more specifically, you should think just exactly why this is...
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Celestron C100ED w/ Moonlite focuser
6" f/9.25 Newtonian - GEM
Meade 10" f/10 Schmidt-Cassegrain
18" f/4.5 Newtonian - Dob
4mm & 5mm TMB SMCs, 6mm, 7mm, 9mm, 12mm UO HD Orthos, 4.8mm, 7mm, 11mm, 16mm, 20mm TV Naglers, 24mm, 32mm, 40mm TV WFs, 55mm TV Plossl.
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cvedeler
Carpal Tunnel
Reged: 12/20/05
Posts: 2164
Loc: Scottsdale, AZ
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Achro's can produce some nice images. They can basically work to get you hooked until you want to get better and better images. Once your standards reach a certain point your equipment becomes the limiting factor. Lance Armstrong on a Wal-Mart bike may be able to beat me hands down, but he wouldn't have ever won the Tour d' France with one. An Achro refractor can produce some pretty nice images, but if you are interested in better and better images, no amount of processing will give you what you can get with a better APO. Of course better gear costs more and so it isn't for everyone. There is something to be said for really just enjoying and getting the most with what you have.
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Chris Vedeler
Astro-Physics 160EDF
Astro-Physics 900GTO
Q453HR / QHY8 CCD camera
Canon 450XSi
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www.aznightsky.com
Scottsdale, AZ
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GlennLeDrew
Pooh-Bah
Reged: 06/18/08
Posts: 1304
Loc: Ottawa, Ontario, Canada
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When imaging extended objects such as nebulae, it's not the linear aperture which matters so much as f/ratio. An 80mm f/5 will record the same image 'density' (to use a term from film days) as can a 300mm f/5. Where the difference lies between these two examples is of course image scale and detail recorded. (And it goes without saying that the larger 'scope will record much fainter stars by virtue of its longer focal length.)
A viable expedient in the war against CA is a minus violet filter. Or for a bit more aggressive taming of the hated blue halos, a pale yellow filter could be tried.
Note that longitudinal CA takes a form where toward shorter wavelengths it grows exponentially. For example, and in a very simplistic way, lets say that in the 10mn interval between 450nm to 440nm CA increases by 10%. It could well be that in the same 10nm interval between 440nm and 430nm CA might increase by 20%. So a cut-off applied at just the bluest end of the spectrum can pay significant dividends in reduction of 'blue bloat', without inflicting any real color cast. Moreover, that small amount of bluest light filtered out of the image will result in almost zero impact on limiting magnitude because it's only going into the out-of-focus 'fuzz' anyway (and which is visible only around the brightest stars to boot).
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Home-made 11X50 right angle bino, 8.1 deg. FOV
Modified 26X100 bino, 3.5 deg. FOV
Home-made Mk II RA bino, using interchangeable objectives and eyepieces
My Gallery
Mediocre minds discuss people. Good minds discuss events. Great minds discuss ideas.
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DonBoy
member
Reged: 09/06/07
Posts: 29
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I have a different slant on the performance of the 120ST for my bag is video AP and I have experienced images as appears in Rick's unprocessed image with my 120ST. My desire is to have live images with the least artifacts, the haloing of chromatic aberration is definitely evident using my 120ST. Before I had the 120ST I was using my C80ED for wider FOVs and picked up the 120ST to give me the same FOV as the C80ED but twice the speed in image capture f/7.5 to f/5. I immediately noticed what appeared to be lower quality images, which was due to the bloating of stars caused by chromatic aberration and resulted in lower detail sharpness. So I picked up a Megrez 110 and my video image quality is back at the level I would want.
The 120ST is a very fine scope when used for the proper application. It just didn't work for my app.
Don
W3DAL
Celestron C8 SCT
Megrez 110
Celestron 80ED
Orion 120ST
iOptron MiniTower
LXD650
Stellacam II
NexImage
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Raven911
Carpal Tunnel
Reged: 03/12/05
Posts: 1815
Loc: by Cloudcroft, NM
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Quote:
Quote:
Too many pics out there from 80ed's.
And let's just think why this is? Or more specifically, you should think just exactly why this is...
I think a lot of it is because everybody says "start with an 80ed. It will be easier."
They are nice, but they have sort of become the Mickey D's of imaging.
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http://smg.photobucket.com/albums/v287/Raven911/Astrophotos/
http://www.eye-of-the-raven.blogspot.com/
My list of second-hand and home-made stuff:
Celestron SC6
Celestron C9.25
100mm F6/76mm F4.5/80mm F5/SV NHII 80mm F6 Achros
SBIG ST7/Canon 300D/DSI Pro Mono/Starshoot DSCI
8 inch F7 Newt on Edmund EQ
8 inch F4.5 Project Astrograph
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Igor
super member
Reged: 04/20/06
Posts: 126
Loc: Croatia
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Has anyone tried to take photos using achro and DSLR but focusing first on red wavelength then green and then blue, throwing out the other two channels which are not focused properly (something like RGB imaging but using bayer matrix as filters) its a lot of work but could be done, right?
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GSO 250/f5 dob
Skywatcher Explorer 130p @ EQ3
Baader modified 350D and bunch of old M42 lenses
Edited by Igor (11/03/09 04:46 AM)
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jayscheuerle
Post Laureate
Reged: 01/16/06
Posts: 4076
Loc: S. Philadelphia, PA
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Aside from the difficulty of focusing that way, you'd be throwing out two thirds of your light! At a certain point, a small apo seems like a wiser choice. - j
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Fight indignorance!
The Green Goblin - 12" of dobsonian excellence!
The PortaBowl-a $100 4.5" f/8 ball-scope YOU can build!
Eero2-a 6" f/5 ball-scope you probably can't. 
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BradC
sage
Reged: 01/31/07
Posts: 448
Loc: St. Louis, MO
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Quote:
Has anyone tried to take photos using achro and DSLR but focusing first on red wavelength then green and then blue, throwing out the other two channels which are not focused properly (something like RGB imaging but using bayer matrix as filters) its a lot of work but could be done, right?
I can't imagine how you'd focus on a specific wavelength with any accuracy if you didn't filter out the other colors.
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My God! It's full of stars!
Zhumell 10" dob - First Light Report
Celestron OptiView 10x50 LPR Binoculars
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