Quote from: Audionut on July 15, 2014, 03:28:31 PM
Care to upload the CR2? 100/1600 and 100/2500.
Quote from: a1ex on July 15, 2014, 03:39:15 PM
2500/100 is more like 2500/80, since the intermediate gains are the ones of the base ISO. Dual ISO only operates on the full-stop amplifiers.
Shadow noise should be equal in 1250 and 1600. In 2500 is lower, because it's based on 3200.
Ok, I had not kept my tests yesterday, but I had increased only shadows on Camera Raw to see the difference (it was a mistake, see below)
Today I made a new test with these values: 800/100, 640/100 (more like 640/80 as stated a1ex) and 400/100
Here are the results (they are 100% crop of a dark area):
800iso :
high res : http://i.imgur.com/hHrpgUh.jpg
640iso :
high res : http://i.imgur.com/RDJlhAW.jpg
400iso :
high res : http://i.imgur.com/sHbzzbs.jpg
We can see that the three images do not have equivalent exposure if exposure increases equally, despite compliance photographic units (I had not seen the difference yesterday).
(a1ex & Audionut, merci pour vos réponses, et surtout un grand merci pour votre travail)