Originally posted by joodiespost so I just want to get this right. ISO 200 has same image quality as ISO100?
It depends on what sensor (or sensors if comparing) you are dealing with. If ISO 200 is the native ISO of the sensor, and ISO 100 is achieved by the firmware then 200 will
probably produce less noise than ISO 100. If, OTH, 100 is the native ISO for the sensor then it should be less noisy. It is unlikely, however, that you would be able to see the difference unless you are specifically looking for it, and looking very critically at that. If you are comparing two different sensors, then all bets are off as there are many other factors that affect noise.