I often get asked questions about photography at prep football games so I thought I would share a two-frame sequence for a discussion topic.
These photos are of Curtis High receiver Stan Langlow in last Friday's game against Puyallup using my Canon 1D and a 300mm 2.8 lens. The first image was made with direct flash mounted on top of my camera body via the hot shoe. The flash didn't recycle quickly enough to fire in the second image so you can easily see the difference between fill flash and ambient (aka natural) light. I also brightened this frame in Photoshop otherwise it would have been too dark to publish.
Proper exposure at Curtis High stadium was 200th of a second at f2.8 at 1600 ASA. I expose manually and use the rear panel LCD to confirm my results. Shooting at that low shutter speed without flash means you will get movement in the photo and a lot of dark shadows under helmets. Most people prefer full illumination in their photos while most photojournalists do not. We'll use ambient light over flash any time we can.
Direct flash at football games produces a lot of nasty reflections and the classic "red eye" effect if the subject's looking straight at the camera. The only way around this is to have a flash off camera which has to be fired using a radio transmitter. This works for Sports Illustrated but its not practical for me or you at a high school game.
These are choices pros make all the time. I've softened my aesthetic stance at prep football because often there's just not enough
ambient light to properly expose the action. Any questions?