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michaelavis
18th June 2010, 05:10 PM
I read in a mFT review that they perform better at ISO200 than ISO100 because the dynamic range was wider. I can't think where I saw it but it's been lodged in my head ever since. Ive taken to setting my P1 to ISO200 as its default but Im left wondering if my E600 should also default to ISO200 given it's got pretty much the same sensor.

I always thought lower the better when it came to ISO for obvious reasons. Anybody know what this is about or have I mis-interpreted something?

theMusicMan
18th June 2010, 05:15 PM
No, you've not misinterpreted anything, it's just the optimum ISO on the E3's sensor is ISO200, I guess though a different sensor, that it's the the same for the E620/600.

michaelavis
18th June 2010, 05:48 PM
Thanks for that - learn something everyday

snaarman
18th June 2010, 05:50 PM
Yes. I almost always use ISO200, never lower, just sometimes higher if darkness dictates.

The theory is that (compared to ISO200) you hit the sensor with more light and turn the gain down when you set it to ISO100... In these circumstances it's a lot easier to saturate the sensor thereby knocking a bit off your dynamic range.

Going the other way, you starve the sensor of light at ISO800 but turn up the gain to get the picture back, and with it comes some noise. That's Physics for you.

I guess the idea is the sensor is optimised for ISO200 not ISO100 because its already clean enough at 200 (some may disagree here...). Having done that then its less of a stretch to get to ISO800, 1600 etc.

Does this make sense-or not ??

Pete

OlyPaul
18th June 2010, 06:07 PM
The only real reason now for shooting lower than ISO200 is if you need a longer shutter speed .:)

michaelavis
18th June 2010, 08:44 PM
Yes. I almost always use ISO200, never lower, just sometimes higher if darkness dictates.

The theory is that (compared to ISO200) you hit the sensor with more light and turn the gain down when you set it to ISO100... In these circumstances it's a lot easier to saturate the sensor thereby knocking a bit off your dynamic range.

Going the other way, you starve the sensor of light at ISO800 but turn up the gain to get the picture back, and with it comes some noise. That's Physics for you.

I guess the idea is the sensor is optimised for ISO200 not ISO100 because its already clean enough at 200 (some may disagree here...). Having done that then its less of a stretch to get to ISO800, 1600 etc.

Does this make sense-or not ??

Pete

Makes total sense, even to me. Thanks Pete.