White Balance/Continuous High speed shooting

Just been to Motor GP in Doha, night race, and I noticed that the second shot that the camera took when shooting a burst was decidedly "cooler" than the first and third. Anyone hazard a guess why?

Camera (7D) was set to AWB, TV, AI Servo, single point focus, high speed continuous, Evaluative metering.

AWB is the reason why the white balance will change for each exposure. If you want consistant shots set WB to a value and also shooting manual is the only way.

Took high speed continuous pictures of my wife who wasn't moving at 200 mph! Completely static, and second was consistantly cooler.

Artificial lighting varies in color during its voltage cycle. High shutter speed + burst catches it at different points in the cycle.

The ONLY way to get around the problem of gas-discharge (which is operating at power-line frequency) lighting's color/intensity problems is to use specific shutter speeds. For a location with 60Hz power, the shutter speeds should be 1/120, 1/60, 1/30, or 1/15 second.

Fluorescent lighting that has line-frequency ballasts will create the same problem as the outdoor lights mentioned in the OP. AWB is not really the problem. The problem is that the color and intensity of the light from these gas-discharge light sources changes throughout each half-cycle of the power.

Thanks, would never ever have thought of that! Saves a call to CSC!

One correction....

There is another way to overcome the gas-discharge lighting quality problem. That is to use a flash source that can overpower the horrible ambient lighting. At a race track, you'd essentially need controlled lightning bolts to do the job, though.

SkipD wrote in post #14234609
The ONLY way to get around the problem of gas-discharge (which is operating at power-line frequency) lighting's color/intensity problems is to use specific shutter speeds. For a location with 60Hz power, the shutter speeds should be 1/120, 1/60, 1/30, or 1/15 second.

Just because you operate at a harmonic of the lights frequency , does nothing to control the phase relationship .
A picture at the the fundamental should work as this will capture a full wavelength of the lighting system .

SkipD wrote in post #14234609
The ONLY way to get around the problem of gas-discharge (which is operating at power-line frequency) lighting's color/intensity problems is to use specific shutter speeds. For a location with 60Hz power, the shutter speeds should be 1/120, 1/60, 1/30, or 1/15 second.

Foggiest wrote in post #14234849
Just because you operate at a harmonic of the lights frequency , does nothing to control the phase relationship .
A picture at the the fundamental should work as this will capture a full wavelength of the lighting system .

You do not have to make the shutter start in sync with the power line voltage cycle. All you need to do is capture light during one or more complete half-wave cycles of the power. 1/120 second (where 60Hz power is used) will capture one half-wave cycle regardless of where in the cycle it starts or whether the power is in a positive-going or negative-going half wave cycle at the beginning. The other shutter speeds I listed capture light over two, four, and eight half-cycles of the power respectively.

Ah yes , I did get that wrong , sorry !
Dunno how , I am sure you have posted that before and I agreed ?
Apologies extended to all .