Quote:
Originally Posted by Stonius
Thanks Dunk, That gives me a good frame of reference for my own experiments.
I thought (perhaps wrongly) that it is best to use the native ISO of the camera, in my case 800. Is that correct?
|
Markus, it's a double-edged sword. On the one hand, we want our data to be as "pure" as possible, on the other hand we actually want to see some signal
800->1600 is only one stop, would probably be my pick. I've used 3200 on my 6D, which has a similar native ISO, and it works well. It'd be worth experimenting. Every camera, whether it be a point and shoot, DSLR or a dedicated astro cam has some degree of gain factor applied. It's just a question of finding the sweet spot.
The thing with increasing the ISO above native is that while you amplify the signal and some sources of noise, the read noise of the camera is constant (isn't amplified) so ends up effectively decreasing with respect to your (amplified) signal...