This photo was during the Georgia Tech vs. Brigham Young 28-19 at Grant Field on September 21, 2002. [NIKON D100, 200.0-400.0 mm f/5.6, Mode = Aperture Priority, ISO 200, 1/1000, ƒ/5.6, (35mm = 345)]
I see photographers talking about what ISO they choose to shoot sports on social media. But don’t they know you are always trying to pick the lowest ISO possible?
Some photographers post these comments on social media, saying, “is it possible to get sharp, relatively noise-free images at ISO 16,000? I pushed it to see what I could get away with, and I hit my level of noise tolerance.”
Why would you ever shoot a higher ISO if you can get away with a lower ISO?
The top photo was with my first digital camera, the Nikon D100, back in 2002. The game was an early evening game. This photo was taken before sunset when there was still good light. At this point, the sun was low in the sky but still had ample light. The lighting conditions allowed me to shoot at ISO 200.

Photography is all about tradeoffs.
The tradeoff is due to the Exposure Triangle, where you balance 1) Shutter Speed, 2) Aperture, and 3) ISO.
In the days of film, this was a more significant tradeoff than today due to film ISO being much more limiting than today’s digital ISO.

You can watch the play action in the photo above of Florida State vs. Georgia Tech is here on YouTube.
Go back and search for football photos before 2000, when most photographers were still shooting film. Then, the noise didn’t exist, but the grain was very noticeable in sports photos.

As we know, you can usually only get two of the three parts of the Exposure Triangle. Sports photographers want to freeze the action and have it in focus. Therefore they sacrifice ISO.
As long as you emphasize sharp and in-focus photos, I suggest you will always be shooting the lowest ISO to make this happen.

Sometimes photographers will choose a deeper depth of field because focusing isn’t ideal, and to ensure an in-focus photo, they then have to increase the ISO.
Other photographers shoot faster shutter speed to avoid motion and bump the ISO.
Bottom line, I think all the veteran professional photographers I know shooting sports are always looking to shoot the lowest ISO.
Today with some of the post-processing possibilities, we are not as limited in our choices.
