Originally posted by kirbic:
Originally posted by Simms:
Has anyone else ever seen this? - I plan to run a few tests this weekend but if it has any truth then I will be pretty shocked. |
I seem to remember seeing some actual data that supported this idea... but the bottom line is, the results of the "intermediate" levels are never going to be worse than the next-highest "native" ISO, so does it really matter?
I have always used the "native" ISOs anyhow; I don't see a big benefit to an intermediate ISO. I guess the only way I'd use intermediate ISO would be in an auto-ISO situation, with both shutter speed and aperture locked. This isn't even possible with my camera, so I'm not so worried about it, LOL. |
Maybe not from a noise perspective, but a lot of chat talks about the dynamic range being hit as a result.
"Higher end Canon models implement ISO gain via a two-stage amplification system; one amplifier for the "main" ISO's 100-200-400-800-1600 etc, and a second-stage amplification to implement the "intermediate" ISO's 125-250-500-1000 etc. and 160-320-640-1250 etc.....Lower end Canon models do not perform analog amplification for the intermediate ISO's, rather the intermediate ISO's are implemented by a multiplication of the raw data in software after quantization, and there is only a single stage amplification in hardware; strictly speaking, they do not have intermediate ISO amplification." |
