I recently purchased a Canon 40D, upgrading from a decrepit 20D that was on its last leg over a year ago. I'd found myself shooting at ISO 200 most of the time, even in broad daylight because I didn't really see a quality difference between 100/200.
I've heard a lot about the 40D having a lot better performance at higher ISOs, so my question is this:
How do I test the performance between 100/200/400 on the 40D? To define: By performance I am referring specifically to: Image Quality, Graininess, and Color quality.
Is there a testing swatch that y'all would recommend, or should I look for a specific scene, should it be darker or brighter out...etc.
As an aside, I was also curious about the "intermediary ISOs." 320, 1000, etc. Someone suggested that these might be software implementations, like to achieve 320 the camera really shoots at 400 with at 1/3 stop over exposed Tv and 1/3 underexposed Av. I ask, because if it is just doing that, I can do that on my own, and control the situation better...but, if it is actually capturing the shot "differently" then I'd use those values.
Thanks in advance.
