At the weekend in the large marquee I once again encountered the situation of a reception lit with LED uplighters round the walls that it was just impossible to get an accurate white balance as there is the most terrific pink/magenta cast on the 5D2 & 5D3. It did look a bit pink in the room to the naked eye but when seen by the Canon sensor it was much exaggerated. I tried AWB. I tried a custom white balance using an Expodisk (this allowed me to replace a pink cast with a green cast). I ran through all the WB presets. I cranked Kelvin from one end of the range to another. I tried using the Green/Magenta offset WB screen. None of these methods could produce a decent white balance. Does anyone have any suggestions as I seem to encountering these LEDs from hell more & more frequently. The problem is that these lights (which I have encountered in quite a few venues) make the venue look mildly pink to the naked eye but the whole room looks bathed in a vivid magenta glow to the camera sensor.

I'm guessing that you'll have a devil of a time getting accurate colors if the LED instrument is not casting a full-spectrum of light. You might be best off putting up your own light source, and keeping one light on-camera for fill. That way, at least when someone is within the range of your lights, you'll get accurate skin tones while the rest of the room still reads pink. Have you tried setting your saturation/color profile to flat? You don't want to add saturation to an already super-saturated light source.

Hi Nigel,

After countless frustrations regarding exactly your situation, I have to side with Oren here and recommend your own lighting. As long as people in your shot are white balanced correctly, you'll probably have to forget about the background colors which will remain that ridiculous pink shimmer. And the good thing about the 5d (I'm also shooting with the 5dmark2) is that it's pretty responsive to even a little self-provided lighting (I have a Belcor on-camera at the dimmest setting) and it colors most of the people in my crowd shots just right.

My experience, LEDs screw up and saturate everything and there's no way to get the look right in the camera. I posted about this in another forum and was instructed to desaturate using Colorista II. Here is the resulting attempt, both "as shot" and after mostly desaturated.

Colorista II -60 Master Saturation Test on Vimeo

I prefer the "as shot" ones better, it looks like natural stage lights of different colors.