[ATMoB-discuss] DSLR able to be used for astrophotography

[George Roberts]

> I'm looking for a DSLR for use both for general photography and 
> astrophotography.

There was some discussion about this a few weeks ago.  I particularly liked John Boudreau's email on the subject here:

http://lists.atmob.org/pipermail/atmob-discuss/2006-November/002821.html

For more discussion go here:
http://lists.atmob.org/pipermail/atmob-discuss/2006-November/thread.html
And click on the threads mentioning "Best <$400 camera for astro photography"

Isn't it bad to get lots of pixels?  Because then aren't the pixels smaller?  Which means they collect less light?  It might be good to get as few megapixels as possible but I don't think you can get much less than 5 in a DSLR.

I have the Nikon D70 and I absolutely love that camera.  I don't use it for astro but tried it out a few times at night.  I don't think you can do exposures longer than 30 seconds so check that particular feature in the cameras you look at.  Most of these cameras do an auto dark frame subtraction for you which is annoying if you take lots of pictures because you only need one dark frame per temperature/exposure (as the camera cools it has fewer "hot" pixels).  

For general photography, the DSLRs are just awesome.  They take the picture much faster (my old point and shoot digital took a whole second which is plenty of time for my kids to run from one end of a room to the other).  They have better built in auto focus, I can use my old powerful flash, I have lots of lenses, mine takes 3 pics per second,and it holds about 1000 pictures and the batter lasts for months between recharges (that's a few thousand pics).  For an idea of the speed of taking a picture - I photograph my kids at basketball games and I can punch the shutter button when the ball is up in their hand (instead of on the floor) every time I take a picture *and* I can get 5 continuous bounces no problem without missing any.  The camera is adjusting focus (you need that with F/2 135mm when subject is running towards you) and exposure between each of those 5 pics also.

- George Roberts
http://gr5.org