ray*j*gun
Veteran
If I need high ISO I shoot my D610.... pretty much sees in the dark! My M8u is superb for what I like to shoot at, which is 160 up to 320. With film I use 200 to 400 rarely above 400.
A quick look at the data from 60,000+ exposures in my Lightroom catalog made with the cameras capable of up to ISO 25600 exposure setting shows that ~96% of my exposures have been made with ISO 1600 or less.
But ... Which digital camera would I pick, one fixed at ISO 200 or one fixed at ISO 2000? Neither. Because neither has the flexibility I expect of a digital camera, both at high AND low sensitivity settings.
Yes, dynamic range changes with sensitivity settings in digital cameras. It does with film media too. As also does acutance and latitude. I use these characteristics of the recording medium, film AND digital, to make decisions about exposure to suit a subject's dynamics to the photo I see in my mind.
A film camera for which you only buy ISO 200 film is not limited to ISO 200, that's just a choice you make which you can change at any time. A digital camera limited to ISO 200 or ISO 2000 can only be used at that setting, period, it's no longer a choice. That makes such a camera undesirable to me.
G
Easy:
If you could only shoot at 1/2000th all year long, then select iso 200 to use all year.
If you could only shoot at 1/200th all year long, then choose iso 2000 to use all year.
The real question is if you could only use one aperture, one shutter speed, and one iso for a year, which would they be?
I wonder quite often why so many posted comments at RFF mention that they needed high ISO. This is seen when the M9 is criticized as not doing well at high ISO settings.
I got this idea: if you were given a camera that was set for one year to ISO 200 versus a camera that was set for one year to ISO 2000, which camera would you be using in 2015, and why.
My wish is for a full frame camera that can give me 3200 ISO that looks no worse than today's 400.
That would allow me to work indoors at around 125th of a second with decent depth of field. My job often has me shooting aquarium and museum interiors during visiting hours so no flash or extra lighting.
Thank you very much, Willie, for you very detailed feedback to my simple question. I worry most about somehow degrading the overall qualities of an image when choosing higher ISO settings on a digital camera. With film, we chose the ISO when we chose the film. MF cameras with inter-changeable backs were praised for providing the flexibility to switch between color and B&W film of different ISO. With the modern digital cameras, we don't need such camera backs anymore.
If you choose ISO 2000, don't forget to bring you Big Stopper 😀If you choose ISO 200, don't forget your tripod and flash. 😛