M9 intermediate ISO settings

[bubuli]

I came across this thread and found it quite interesting...

I'm not saying that the Wolfus guy is wrong, but I think increasing the ISO in a digital sensor is more to just increasing the analog signal amplification.

When I had Nikon DSLRs (not sure if it applies to Canons), you also have Hi or Lo 1 & 2 settings in addition to the standard ISO settings. If it's truly just an analog signal amplification, why even bother with "Hi" and "Lo" ISO settings and just use the numerical equivalent?

Ha! Oddly enough, I just started reading today's article on Steve Huff, and, coincidentally, Ofri Wolfus briefly mentions how sensors have a single ISO, and gain is added after the fact:

I Shoot Digital Film by Ofri Wolfus | STEVE HUFF PHOTOS


"...Another little known fact is that a digital sensor has a single sensitivity to light. Increasing the ISO in the camera simply increases the amount of analog signal amplification, but the sensor’s sensitivity to light remains unchanged.

At this point lets stop for a second and look back at what we have. Surprisingly, this mechanism is extremely similar to how we work with film. First, we expose the film to light. Then we develop the film, at which point we can push process it, effectively increasing its ISO and adding “noise”..."

 

[douglasf13]

When I had Nikon DSLRs (not sure if it applies to Canons), you also have Hi or Lo 1 & 2 settings in addition to the standard ISO settings. If it's truly just an analog signal amplification, why even bother with "Hi" and "Lo" ISO settings and just use the numerical equivalent?

Lots of cameras have Hi and Lo settings (although they are named differently.) This is simply pushing or pulling the file digitally.