Motorsport at night requirements

My experience is based on first hand with 70D and compare test images between 70 and 80D. I also own Canon 100-400.

So first will be wise to set exposure compensation to -1 (or -1.5) because on the place will be dark and you want to show the darkness. In post do not push much the shadows. Then you can set the ISO to Auto and limit it from above. You can try ISO 6400 also.

Also consider some photos on much lower speed to show the motion.

At the end is better to have grainy photo instead of not having it at all.

P.S. Based on my personal experience light is never enough :)

There are two strategies. First is making the kind of pictures that might accompany a sports page story focusing on race results…the critical pass that illustrates what the text describes.

The other is to make the pictures that can be made easily. Where the light is good and the cars are slow. For example at the apex to a hairpin.

Or in the paddock and pits where the off the track dramas unfold, the subjects are not at racecar speeds, and the light is better… you can even bring a flash.

The advantage of making the easier pictures is that you don’t have to throw money at the optical problems that exist on track. What you need there are 500mm f4 fast autofocus lenses and a top end body with excellent high ISO performance. A press pass probably helps. And even with all that you are likely to get pictures that look like other people’s.

If you embrace the limits of your gear, you can make pictures that others won’t make. If your camera makes noisy pictures, it’s ok if the picture tells a story about the racing . It is more interesting than a story about how good your camera is.

It all depends upon how bright the lights are at the specific track you'll be at.

There's a wide variation between the dim lighting typically found at a small, local dirt track and the lighting found at major televised races for series such as NASCAR or major drag racing circuits.

Without knowing the exposure parameters for the photo of the track at your link, it's impossible to know how bright they are by looking at a still photo (if that is even a photo rather than CGI). But even at the very wide angle pictured, the cars on the track appear to be rather blurry due to their motion during exposure.

Even at the TV tracks, I'd recommend an f/2.8 constant aperture lens rather than an f/4 that only goes to 200mm or a variable f/4.5-5.6. The 100-400mm is pretty much a daylight lens. You might squeak by with a 70-200mm f/4 if you can get very close to the action and thus not need to worry about cropping that much.

The nice thing about road tracks is that often the most photogenic moments occur in the corners when the cars are going slower than on the straights. There will usually be one or two corners that are the places drivers will attempt to 'outbrake' their opponents by going deeper into the approach to the curve before slowing down more rapidly. This causes them to exit the turn slower, but if they can skillfully block the car they've just passed exiting the turn they'll force the other car to slow as well. Try to find a spot so that you are facing the cars as they exit one of the key corners.

Also pay attention to whether they are more brightly front lit or back lit exiting the turn. If back lit, consider another corner with more favorable light at the exit.

If you get a chance, watch a few videos of races at the track to see which turns are usually the ones were positions are most often contested. Or take the opportunity to ask a person who has attended races at the track, or even ask one of the drivers if the opportunity presents itself.

There's rarely ever "enough" light when shooting night sports. It's almost always a compromise between the amount of noise you find acceptable and the amount of motion blur you can live with. Most often it's best to do whatever you need to do to keep motion blur to a minimum and then deal with/live with the noise.