At least once a week on a photography workshop someone will ask me: “How far can I push my ISO?”
I used to answer that it depends. It depends on the camera you have, it depends on what you are going to do with the images, either print or simply use them on social media, and it also depends on your taste, whether you like grain or not.
This is very straight forward but I always felt that the person wasn’ entirely satisfied with my answer. They often don’t know what they’ll end up doing with their pictures and maybe they were just expecting me to give them a number. That would be easier right? How far can I push my ISO? 800! Done.
So what happens then when you enter a dark house and need an ISO higher than 800? Do you just pack your camera and go home because you are not supposed to push the ISO higher than that?
Now I do answer something different.
Now I tell people that this is not a relevant question. You can push your ISO up to its limit if that helps you get your shot, and this is the only thing the ISO is here for.
You are not being creative with your ISO. Unlike the Aperture and the Shutter Speed, the ISO does not’ enter the creative process (unless you are trying to give your images a grainy feel).
The ISO is only here to help you deal with dark situations, and if you shoot at night with only a few candles as light source and your ISO needs to be at 10,000 so be it.
Of course, as a photographer, you should try to avoid pushing your ISO that high. You have to understand your camera and see if you could not find other ways to deal with such dark situations. You could try to use a lens with a wider aperture to let more light in, or try to reduce your shutter speed as slow as you can to give more time to the light to come in without motion blur. You could also underexpose your image to avoid pushing your ISO that high.
But at the end, it is only about your final image and the work on the light and composition you have done. As I talk about here, photography is not about your camera settings. When I see your image and I tell myself “Wow!”, do you know how much I care if it is grainy because your ISO was high? Yes, you’re right, I don’t care at all.
You got me into your image because of your composition, your creativity. The rest doesn’t matter.