Hi Adz,
The photos you have listed look like they are all taken with a DSLR and a widefield type lens. A stock 18-55mm lens at 18mm should give you the field size shown in these photos, but you will probably find that these cameras are mounted "piggyback" style on the top of a tracking Equatorial Mount in order to keep the stars from blurring. If you just use a tripod, you will need to limit your exposures to around 30 secs MAX as the rotation of the Earth causes the stars to "blur" as they glide past the stationary camera....this can get frustrating....
With a tracking dobsonian, this is lessened somewhat, but as it is an ALT - AZ mount (up-down axis and left-right axis) then it does not turn in a circle when tracking like an Equatorial Mount does and therefore what ever you are tracking, will rotate as time passes, meaning when you try to stack any photos together (to bring out more details and light) it will be difficult to keep the pics all aligned properly.
If you are serious about Astrophotography, you can buy a scope like mine which is quite reasonable in price and can give you good results with a DSLR (with a T ring for it where the lens goes) by using the telescope as a BIIIIIG lens effectively.
Check out my post
here showing you the scope itself and the decision process in the thread (again, the price has increased from when I bought it) as well as
here,
here,
here and
here for some pics I have taken through it of nebulae and globular clusters using a Canon 1000D DSLR.
Processing these images is often harder than capturing them, although, things like guiding your mount to keep the stars sharp can be hard, and involves more money and technology. This is where it starts to get expensive.
With a good entry level DSLR like the Canon 1000D or 1100D, 550D etc and the stock lenses on a tripod, you can take wide field shots of the sky or even one like that close(ish) Eta Carinae shot (the blue one) but will be limited to exposure length before the stars blur unless you use some sort of tracking....
The tracking dobs are FANTASTIC for planetary captures of Venus, Mars, Saturn and Jupiter using a Webcam inserted into the eyepiece connector and a laptop, however, to get close enough, you will need at least a 2x or 3x or even a 5x barlow (magnifier) to get good details and at least an 8inch scope or bigger....
The other advantage of the tracking / goto dobs is as I mentioned before, is that whatever you want to look at can be dialled up and then when on target, will stay there for as long as you want. As you up the magnification, with a manual non motorised dob, you will CONSTANTLY have to keep nudging the scope slightly to keep the object in view as the Earth spins quite fast, especially when you are looking out so far away....
My advice then is to start cheaply with a great VISUAL telescope like a GOTO dobsonian as I have recommended (the 8" or bigger) and keep costs down until you either 1) have more interest in astrophotography or 2) find that it isnt really for you and can recoup most of the money invested by selling the gear second hand here or 3) Decide its AWESOME fun and get into planetary pictures or get aperture fever and upgrade to larger and larger scopes to chase new objects or simply become hooked.
Sorry for the blurb, I ramble sometimes....
Cheers
Chris
Quote:
Originally Posted by cyrax83
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