Question for Jeff Foster and Dave Kommel

[Jody Lang]

Does anyone know if this has happened in the super gas/comp classes?

[Dave Kommel]

Originally Posted by Toby Lang

Do all photographers at the track use modern DSLRs?

And what about external flashes? How long of a delay is there after pressing the shutter and the flashes going off? Is this delay adjustable?

It's possible to have the internal flash off and still be sending a signal to the external flashes, right?

99% are using modern DSLR's. You might have friends and crew shooting with point and shoot cameras that use infrared focusing.

When you talk about external flash, I assume you actually mean remote flash. The on-camera flash units we use do have infrared, but it only functions to help the camera focus in very low light situations. Auto-focus is based on contrast and when there is not enough light for the camera to discern contrast, it uses the flash to help it focus. In the Dan Mason situation (daylight), there should not be any infrared at all, so if the photographer (possibly me) caused the redlight, it had to be flash and not infrared. Also, if the flash is turned off, there is no infrared in any situation.

Remote flashes are triggered by a cable, a radio slave unit or they can be triggered by the flash of the on-camera flash. No infrared is involved.

Shutter lag in modern DSLR's is very short, somewhere in the 200ms range and is not adjustable. The flash should fire instantaneously when the shutter opens.