David Macias
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<dmaci...@earthlink.net> wrote in message
news:20030918152251.747$V...@newsreader.com...
Yeah, I thought like /ALL/ cameras in the $500 range had at least 400.
But I don't think I'd use it for night shots! I don't know how fast
the aurora borealis fluctuates in shape but I don't wamma shoot dark
backgrounds with anything other than 100. So ASA 100, F2.0 (or as wide
as it will go), and shutter 1sec. ~ 1/4sec. on a tripod! Even if you
have to go faster to freeze the motion just do what the telescope
(cosmological photographers) guys do and process the image in photo
shop or other. All those pretty purple space clouds you see in
shots are *not* visible in the raw photos no matter what power and
how bright the scope is or how long the exposure was. You can search
around for that specific process and then just modify it a bit to fit
Aurora photos.
The thing is with 200 ASA and above on $500 cameras is that it
introduces way too much CCD noise! This noise isn't /too/
noticable in brightly lit or blueish scenes but in contrast
against the dark of a night sky will look just awefull! Where to
use ASA 400 you ask? Think of a speed boat on an overcast day
at noon... or waterskiier where you want the water plume to
look sharp against the generally monotone color of the greyblue
lake BG... etc. Digital noise reduction will help some but
still...