Difference between Auto WB and Custom WB.

mike_d wrote in post #10136842
Why does it seem that incandescent light is so hard for AWB to handle? AWB does a decent job in many other situations but misses by a mile under a century old lighing technology.

Canon's documented that AWB functions only over the range of 3000-7000 Kelvins. Tungsten WB is set for the studio (Type B) lighting norm of 3200K. Household tungsten lighting is at between 2800 and 2900 Kelvins, so would appear orange under either of these. So setting a custom white balance when shooting under tungsten (household) lights is your best bet. Bear in mind that the higher the wattage of your tungsten lamp, the "cooler" the temperature will be. And "soft white", "frosted", "clear" or other varieties of lamp coatings can also alter the actual colour temperature you get.

Gatorboy wrote in post #10137404
Did you try setting your WB to tungsten?

neilwood32 wrote in post #10137521
It might be due to the cyclical nature of incandescent lighting. As it runs at mains voltage, the lights are actually flickering due to the frequency cycle (50hz in the uk, 60 in US IIRC). Its imperceptible to the human eye which has approx a 25hz refresh (not sure what the correct term is ). As the camera will sample the light in an instant (way less than the 0.02secs of the cycle), it will inevitably miss part of the cycle and hence the WB will be off.

This is also the reason that at certain shutter speeds in gyms and other indoor shoots you get inconsistent exposure across a frame (green or yellow tint at one side)

RAW is of course the easiest solution as you can adjust the WB yourself to suit.
Incandescent is a setting which takes account of the cycling (and doesnt sample the light conditions) therefore giving more consistnt results.

What you've described is actually a problem associated with fluorescent lighting, not incandescent. Because incandescent light results from heating a wire red hot, it doesn't actually cool off enough to flicker. Fluorescent lighting is a gas discharge lighting, similar to your strobe. Between arcs the gas and phosphors can "go out" so you get banding or odd colours if you catch things mid-cycle. And no, the Fluorescent WB setting doesn't compensate for that flicker. The only way to do so is by using a shutter speed slower than the flicker rate. Using a shutter speed that's slower than the camera's flash sync speed but faster than the shutter speed may reduce the problem, but only capturing at least one full cycle on the sensor will actually eliminate the problem.