Because there are alot of talks about the 50ISO being bogus and much worse than ISO100, and other people claiming ISO50 is slightly better I decided to take a test.
It's in no way a lab test but something I think is good enough to show an example.
My own experience with ISO50 was that I had the idea the sharpness was slightly better and the colors were a little bit more intense.
Also there was a very little less noise.
Because with model shots you never have the exact same shot I did this comparison.
You can see it yourself on www.doorhof.nl/test/test50100.zip
My opinion is there is little difference in dynamics, at least with this test.
Colorrendition is different, especially in Yellow and Cyaan on which I like the the ISO50 a bit more overal colorsaturation is about the same or a little bit more with ISO50 (so not much less as can be read on some forums).
Sharpness on ISO50 is better the difference between F9.0 and F13.0 can be discussed about normally you would expect F13.0 to be little bit better.
I choose to not adjust the lights to ISO100 to get F9.0 because I wanted to test the real life changes.
Lens used is a Tamron 90mm f2.8 shot from a tripod, one light source.
For the moment I will stick to ISO50 but I won't hesitate to change to ISO100 when someone proofs me wrong by the way, people learn every day, for the moment the better sharpness and more saturated raw colors pull me towards ISO50.
I love to see your opinions.
Greetings,
Frank
