cam1936
sage
Reged: 08/01/08
Posts: 297
Loc: Alberta, Canada
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Hey everybody. I'm a Canadian with a decent amount of normal photography experience but absolutely no astrophotography experience. I have always been interested in astronomy and have taken astrophysics courses in university but have absolutely no clue how to go about taking astro photos. Recently I have been taking photos of the stars with my DSLR on a tripod, with and remote shutter switch but I want to shoot through a telescope. I have been trying to research on the internet and have looked at most of the beginner pages on this site but am still completely lost.
I want a telescope that would be decent for planets and also decent for deep sky objects, this is because as a beginner I don't want to specialize too much, so does his mean that I want a telescope with about f/7 or so? Looking at the different types of telescopes I like the look of the refractors as they seem like less maintenance and a bit more beginner friendly which is good for a newbie. So if I want a refractor with an f/7 or so value how would a telescope like this be?
http://www.telescope.com/control/product/~category_id=refractors/~pcategory=telescopes/~product_id=09895
Also, once I have choosen a telescope I would like to have a primary focus set-up. I have a Canon 350 D (a DSLR I’m sure most of you know). What sort of adapter would I need to hook it up right to the end of the scope? Also as far as I have read you need a drive to compensate for the rotation of the earth on long exposures but I have no clue what drive I need or how to check its compatibility with the telescope I choose. And last, what sort of tripod do you need for a telescope? I know I am being pretty broad right here but I am willing to research and I just need someone to start steering me in the right direction. As an end note my budget for telescope, drive, tripod, eyepiece and any other little adapter I need is around $1500 - $2000 CAD (almost at par with USD), would I be able to get a decent setup for that amount?
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sang33ta
scholastic sledgehammer
Reged: 07/08/08
Posts: 767
Loc: UK
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go for something on an eq goto mount. low f=ratio is good for faster imaging but if it's at the expense of focal length you'll find it hard to get close to those planets. An 8" SCT f10 with a focal reducer is what I concider a general do all scope.
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Hioptic 152mm f12.5 Maksutov, CG5-AGT, Meade Super Plossl Set, Casio QV-2900UX
Edited by sang33ta (08/01/08 08:30 PM)
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cam1936
sage
Reged: 08/01/08
Posts: 297
Loc: Alberta, Canada
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so would something like this work for a mount?
http://www.buytelescopes.com/product.asp?t=13&pid=5275&m=
And would this fit on any normal sized telesscope?
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C8-SGT
Nikon 10x50 Action Ex
Canon 350D
Manfrotto tripod
Various EPs and accesories
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Patrick
Postmaster
Reged: 05/16/03
Posts: 8193
Loc: Franklin, Ohio
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Hi Cam1936 and welcome to CN! 1936 stand for anything in particular? 
The Orion ED80 that you've singled out is a great choice for astroimaging, particularly DSO's. For planetary imaging, the focal length is probably a little too short.
Unfortunately planetary imaging and DSO imaging have somewhat different requirements in gear and cameras. For planetary imaging the name of the game is 'beating the seeing'. The
'seeing' is atmospheric turbulance. The way to beat the atmospheric turbulance is to use a camera that takes lots of very short images and then toss the ones out that have bad seeing and combine the remainder to reduce noise and increase the signal to noise ratio. The camera that's best adapted to that kind of imaging is a web cam. I'm not an expert on planetary imaging so can't tell you which cameras are best, but a lot of folks are starting out with a Phillips SPC900N webcam and adding a 1.25" eyepiece adapter.
Light gathering is not really a big issue in planetary imaging, but resolution is important. Larger apertures provide more resolution. Having a long focal length is also important so that the image size will be larger (planets are pretty small objects).
On the DSO side, aperture is not as important, but focal length and f/ratio are. DSO's are faint objects and require much longer exposures to capture them. As a photographer you know that faster f/ratio's let in more light than slower f/ratio's. Telescopes don't have adjustable f/ratio's like a camera lens so when selecting a scope for AP, think faster.
The ED80 at f/7.5 is relatively slow, but you can add an f/6.3 focal reducer which will bring it down to f/4.7, pretty respectable. However, as a planetary scope, the focal length is kind of short at 600mm. 1500 to 2000mm or more would be better. Again, with planetary imaging, exposures are short so tracking is not as important either. With DSO's, tracking is very important.
As far as mounts go, the Celestron CG5-GT would be perfectly adequate for the ED80 refractor, even if you add a second scope to autoguide with. Unguided with the ED80, you should be able to get about a minute of exposure without star trailing. With autoguiding the exposure length can be increased substantially...sky glow from light pollution will probably be more of a limitation than the mounts tracking.
Astrophotography has a pretty steep learning curve, so be prepared for that. Ask as many questions as you like. One reference I highly recommend is A Guide to Astrophotography with a Digital SLR...well worth the cost of the book.
Patrick
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Celestron CPC 1100 XLT
10" f/6 Truss Tube Newtonian
Celestron C6S-GT SCT
AT66ED Refractor
Canon XSi; Meade DSI;SPC900-NC
Vixen GP2 Photo Guider Mount
My Astronomy Pages
The heavens declare the glory of God; the skies proclaim the work of his hands.
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s58y
Postmaster
Reged: 12/12/04
Posts: 5631
Loc: Eastern NY
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<<as a beginner I don't want to specialize too much, so does his mean that I want a telescope with about f/7 or so?>>
As a beginner, you probably do need to specialize in either planetary or DSO imaging at first. The equipment used will be vastly different. The ideal DSO starter rig is a small APO refractor (like the one you mentioned), or even telephoto lenses assuming you start with a DSLR.
I have no idea what an ideal planetary starter rig is, but it definitely doesn't include a DSLR.
The reason you want to start small in DSO imaging is that tracking and guiding, which are perhaps the key difficulties in DSO imaging, will be easier with a shorter focal length scope or lens.
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Hutech 30D, SBIG ST-402 autoguider
SV80S, TV102iis
Old camera lenses: 800mm f/5.6, 180mm f/3.4
AP900, Barndoor tracker
http://www.pbase.com/s58y
http://www.flickr.com/photos/s58y/
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cam1936
sage
Reged: 08/01/08
Posts: 297
Loc: Alberta, Canada
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Wow this was very helpful and you had a very in depth answer patrick, thank-you! No the 1936 dosent stand for anything in particular I just needed to place a number at the end of my name for some site and it stuck. I think I will invest in that book as I have heard good things; but I think you guys will still have to answer many more of my questions haha. The good thing about my viewing location is that, while I live in a city of a million people, my parents have an acerage way outside of the city by the mountains and there is only a small amount of light pollution in the very south westren portion of the sky. I go to thier place most weekends and take my shots there. Another question I now have is about autoguiding. What kind of scope and equipment do you need for that? Is it just something small like a spotter scope to center on a known star (like polaris or something) to calibrate itself and move along with the rotation of the earth? That stand I linked says it has some sort of autoguiding port.
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C8-SGT
Nikon 10x50 Action Ex
Canon 350D
Manfrotto tripod
Various EPs and accesories
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Patrick
Postmaster
Reged: 05/16/03
Posts: 8193
Loc: Franklin, Ohio
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Quote:
Another question I now have is about autoguiding. What kind of scope and equipment do you need for that? Is it just something small like a spotter scope to center on a known star (like polaris or something) to calibrate itself and move along with the rotation of the earth? That stand I linked says it has some sort of autoguiding port.
See my Astrophotography website for an example of one way to put together an imaging setup. There are a variety of setup possibilities.
Both of my scopes can be used as either a guide scope or an imaging scope. One is a short focal length 66mm APO refractor, the other is a longer focal length 150mm SCT.
You've got the general idea on autoguiding, but choosing Polaris as a guide star would be counterproductive because Polaris barely moves throughout the night (it's the north star).
The basic sequence for autoguiding is to hook up a CCD camera or webcam to your computer running autoguiding software like PHD Guiding, lock on to a guide star, and then let the software guide the mount by sending a signal to the mount's autoguiding port. A special cable sold by Shoe String Astronomy called a GPUSB cable allows a direct connection from the computers USB port to the autoguider port.
A newer type of autoguiding camera sold by Orion telescopes is the Star Shoot Autoguider and plugs into the computer and into the autoguider port directly from the camera. Another name for the autoguider port is an ST4 port.
FYI, the correct terminology for 'the stand' is the 'mount' and the 'tripod'. It's pretty clear what the tripod is, but the mount is the part that sits on the tripod legs and controls the movement of the telescope. Some mounts are sold separately from the tripod legs, but usually they are the better mounts and tend to be rather expensive.
Patrick
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Celestron CPC 1100 XLT
10" f/6 Truss Tube Newtonian
Celestron C6S-GT SCT
AT66ED Refractor
Canon XSi; Meade DSI;SPC900-NC
Vixen GP2 Photo Guider Mount
My Astronomy Pages
The heavens declare the glory of God; the skies proclaim the work of his hands.
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jay52
Carpal Tunnel
Reged: 09/26/04
Posts: 2509
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Quote:
On the DSO side, aperture is not as important, but focal length and f/ratio are. DSO's are faint objects and require much longer exposures to capture them. As a photographer you know that faster f/ratio's let in more light than slower f/ratio's. Telescopes don't have adjustable f/ratio's like a camera lens so when selecting a scope for AP, think faster.
Just remember, with a camera lens, you change the speed because you are changing it's aperture...so don't say aperture isn't important. For imaging objects, NOTHING is more important. Now, if you want to image widefields, then sure, something with a faster f/ratio will make for shorter exposures. But if you are imaging single objects and are imaging to past the read noise level, then f-ratio doesn't matter.
For more, see the most recent version of the focal-ratio recently posted.
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jay
www.allaboutastro.com
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Patrick
Postmaster
Reged: 05/16/03
Posts: 8193
Loc: Franklin, Ohio
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Jay,
HERE is a link to the thread you were referring to. Interesting read...thanks for pointing it out.
Quote:
so don't say aperture isn't important. For imaging objects, NOTHING is more important.
Just for the record, I did not say aperture wasn't important. I was comparing planetary imaging with imaging DSO's and said that aperture was not AS important for DSO's as planets. Perhaps I was thinking in terms of shorter focal length DSO imaging, but didn't say so. For long focal length DSO imaging aperture would be just as important as it would be for planetary imaging, mainly due to the resolving ability of the larger aperture. But increasing aperture with longer focal lengths also lowers the f/ratio. I've seen a lot of fantastics DSO images taken with small refractors though, so I'm not sure how important it is, particularly for someone just starting out. Taking many subs also helps reduce the S/N ratio doesn't it? And I'd rather take 60 subs of 1 minute each at f/4 vs 60 subs at 4 minutes at f/8.
Patrick
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Celestron CPC 1100 XLT
10" f/6 Truss Tube Newtonian
Celestron C6S-GT SCT
AT66ED Refractor
Canon XSi; Meade DSI;SPC900-NC
Vixen GP2 Photo Guider Mount
My Astronomy Pages
The heavens declare the glory of God; the skies proclaim the work of his hands.
Edited by Patrick (08/02/08 01:46 PM)
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cam1936
sage
Reged: 08/01/08
Posts: 297
Loc: Alberta, Canada
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Well that Orion 80mm ED was on for the deal of the day, down to 380 something from 490 something so I bought it plus a starter 1.25" starter eyepiece kit so I can do some general observing before I start with the astro pics. Now im excited for it to come in the mail!
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C8-SGT
Nikon 10x50 Action Ex
Canon 350D
Manfrotto tripod
Various EPs and accesories
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Rhosheen
member
Reged: 06/06/04
Posts: 91
Loc: Maple Valley, Wa.
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Expect horrible nasty weather for a month starting the day it arrives. 
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Phil Andrews
Hardin 6" DSH
Orion SVP 8"GT
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NyxAither
Pooh-Bah
Reged: 09/11/07
Posts: 1269
Loc: Arlington VA
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tell us how you like it, I'm thinking about getting a scope for tracked imaging
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http://www.astrophotogallery.org/showgallery.php/ppuser/169/cat/500
✸Orion XT8i✸Orion80-T✸CG5 GT✸Meade DSI II✸Meade DSI(TY TODD N!!!)✸Orion 4.5" Reflector✸Mac Powerbook G4✸10x50 binocs✸SPC900NC✸
Thomas
..::*~*Clear Skies*~*::..
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Jared
Carpal Tunnel
Reged: 10/11/05
Posts: 2922
Loc: Piedmont, California, U.S.
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80mm ED is a great way to start out on prime focus deep sky imaging--diffuse nebulae, reflection nebulae, open clusters, and larger globulars, planetaries, and galaxies. The relatively short focal length and light weight will minimize the tracking challenges.
What mount did you end up with? I would recommend a Celestron AS-GT as a starting point. The mount will actually play a larger role in the quality of your deep sky images than the optical tube will, so don't skimp on this. If you want to leave some room to grow (in optical tube size, I mean) you can also look at an EQ-6/Orion Atlas. They are a bit more expensive but the carrying capacity is much higher than the AS-GT so you will be able to try out larger optical tubes and add off axis guide scopes at a later date. Only real disadvantages are the cost and the weight/bulk.
Start with your digital SLR. For images of showcase objects they are as good as anything on the market. Their large chips coupled with the short focal length of the 80ED will allow you to do wonderful widefield work. Eventually, you may want to move on to a dedicated astronomical CCD camera, but that could easily be years away. Many people never feel the need to get an astro camera--particularly when you look at the cost of the good ones. In terms of adapters, you will need a 'T' ring for your camera and a 2" prime focus adapter (assuming the 80ED has a 2" focuser, which I think it does). In the future, I would recommend a focal reducer/field flattener to reduce coma at the edges of your frame. This isn't critical when you are just starting out, though; it will probably be a while before you are able to achieve nice, round stars in even the middle of the picture, so save this one for later.
Finally, it's important to know what you are getting into. The pictures posted on this forum (and in particular the more advanced forums) are not what you can expect to see straight out of the camera. Even if you get all of your equipment working so that you are acquiring lots of good data, the raw images are going to look, well, "uninteresting." To get really spectacular results you will need to spend about an hour post processing for every hour you spend on data acquisition. I go even further than that--my ratio is more like 2:1 in favor of the processing and post work. If you don't intend to make Photoshop your friend, you probably won't really be able to enjoy this branch of the hobby.
Best of luck getting going!
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- Jared Willson
- A few refractors
- A couple of GEM's
- One camera
- Two eyeballs
- Some heavily light polluted skies
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cam1936
sage
Reged: 08/01/08
Posts: 297
Loc: Alberta, Canada
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I was looking at the CG-5 as a mount as it seems to have everything im after. I know I shouldn't have great expectations for my first images but I'm pretty patient and I'm sure I'll get it eventually. You guys have been a lot of help!
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C8-SGT
Nikon 10x50 Action Ex
Canon 350D
Manfrotto tripod
Various EPs and accesories
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Jared
Carpal Tunnel
Reged: 10/11/05
Posts: 2922
Loc: Piedmont, California, U.S.
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Quote:
I was looking at the CG-5 as a mount as it seems to have everything im after. I know I shouldn't have great expectations for my first images but I'm pretty patient and I'm sure I'll get it eventually. You guys have been a lot of help!
Good choice! I used a CG-5 (AS-GT) for my first year of astrophotography and was quite happy with it. Eventually I wanted something that could handle a bit more weight, but it's a good place to start out with a small refractor and a DSLR.
Best of luck, and make sure you post for first images. Even if they are terrible! Nobody here makes fun of them because we all remember how bad our first efforts were. My first couple attempts I couldn't even get my subject into the field of view--I'm sure you'll do much better.
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- Jared Willson
- A few refractors
- A couple of GEM's
- One camera
- Two eyeballs
- Some heavily light polluted skies
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Franklink
super member
Reged: 07/19/08
Posts: 162
Loc: Somewhere Dark
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I have heard good things about the cg-5. Be sure to research guidescopes, because you'll want to guide your images real quick.
I am with Rhosheen. Because Orion controls the weather, expect nasty weather as soon as your scope arrives. This will continue for exactly 30 days. 30 days is the length of the return policy. 
Be sure to post your images, we would all like to see them, regardless of how good they are.
happy imaging,
frank
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cam1936
sage
Reged: 08/01/08
Posts: 297
Loc: Alberta, Canada
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Curse you guys, you're going to jinx the excellent weather we've been having. Is that orion short tube 80 decent for autoguiding? The OTA is really cheap which is good. Im also a bit confused on how to mount the guide scope. Do you only need guidescope rings and one of those guidescop mounting bars? Also can someone list some software that is good for processing astrophotos? I used to use adobe photoshop back when I had a free liscence through school but now im using the software that came with my 350D.
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C8-SGT
Nikon 10x50 Action Ex
Canon 350D
Manfrotto tripod
Various EPs and accesories
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cam1936
sage
Reged: 08/01/08
Posts: 297
Loc: Alberta, Canada
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I'm also a bit confused on how a mount like the cg-5 is powered. I see it can be sold with an adapter which would be great for my rather dark backyard with an extension cord. But what if I want to go somehwere else? Does it have an internal battery or do you have to buy an external one? I've Reading the product specs on a few diffrent sites and still can't tell.
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C8-SGT
Nikon 10x50 Action Ex
Canon 350D
Manfrotto tripod
Various EPs and accesories
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imjeffp
Aluminum Falcon
Reged: 09/30/03
Posts: 4982
Loc: Cedar Park, Texas
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Quote:
Curse you guys, you're going to jinx the excellent weather we've been having. Is that orion short tube 80 decent for autoguiding? The OTA is really cheap which is good. Im also a bit confused on how to mount the guide scope. Do you only need guidescope rings and one of those guidescop mounting bars? Also can someone list some software that is good for processing astrophotos? I used to use adobe photoshop back when I had a free liscence through school but now im using the software that came with my 350D.
Yes. Yes. Nebulosity & Photoshop.
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Franklink
super member
Reged: 07/19/08
Posts: 162
Loc: Somewhere Dark
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Some other software names I have heard are, Iris, and registar. ( I have no experience with either)
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