Hi folks, my thread asking for wide lenses without curvature has turned into a very interesting off-topic conversation about ISO, and whether it is more and less noisy as you increase it.
I thought it deserved a thread of it's own as there is some very good information coming out of it, worthy of discussion among the more knowledgeable members of IIS photographers, both terrestrial and astro.
It started
here, and developed.
Please continue on this new thread here to make it more searchable by topic heading. It's great stuff!
Baz.