Question for Jeff Foster and Dave Kommel

[SSDiv6]

Originally Posted by Toby Lang

First off, I just want to say that flash pictures should NEVER be taken until both cars have left the starting line. What do you think is more important, having a fair race without the possibility of a rerun or getting both cars in the photo? If we took a poll I don't think it would even be close. If you have to have both cars in the photo, go stand on a ladder at the 330' marker or at half track, whatever it takes, just don't take any flash pictures until both cars have left the starting line.

Have you ever tried concentrating on the tree with a camera flash going off in your face? I have. Back when I used to run my bracket car I was racing in Boise at the Nightfire Nationals. I was leaving off the top bulb. When the top bulb was about come on a flash went off in my face. When I could see again the second bulb was on. Not fun. I assume nobody would do that nowadays, but I wouldn't even want a flash going off behind me either. Somebody told me the photographer in the Dan Mason incident was about 10' behind the line.

I did a little research on cameras and they use infrared to trigger external flashes for better lighting. Dave, does your camera have the capability to use external flashes? If so, it uses infrared to control them.

I don't buy that it's the flash from the camera that's causing the red lights. If the sun reflecting off of a finely polished chrome plated front wheel doesn't trigger a red light, then how is the flash from a camera doing it? I bet it's the infrared from the camera that's causing it. Visible light is a different wavelength than infrared and it shouldn't matter how powerful the flash is.

And how many times does it happen when nobody notices it? Let's say a driver is about to cut a .150 light, but the photographer takes a picture at just the the right time and he gets a .025 light? Or a close red light?

I'm with Bill. I'd like to see a demonstration of this happening with just the flash part of a camera. If this can happen with just a flash from a camera, something is wrong. I believe it's caused by the infrared signal sent out by these cameras to control external flashes.

And once again, flash pictures should NEVER be taken until both cars have left the starting line. I hope you will tell other photographers this because there should NEVER be a rerun because of a photographer.

Toby, the flash intensity can be adjusted in much of the professional equipment used at the races.
Many electronic flash systems have a capacitor that can generate several hundred volts and the energy is measured by Watts-Second.
Again, if by coincidence the flash is on the line-of-sight, it can trigger the photocell or infrared.