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6400k bulbs with a green cast

Chris Giles

New member
Hey guys, stumbled across a little problem that I'd like some input on.

I mainly use natural light for portraits but recently I've been making my own ringlights and modifiers. Some of the bulbs I have were used today just to see what effect they would give if any when mixed with natural light.

The bulb temperatures are 6400K and the shoot was in the shade at 2pm in the afternoon. Even if I set the Raw file to 6400k temperature I get the green cast? These were energy saving bulbs from the side.

I use these same bulbs as part of a ring light setup in the studio and there's no green cast?

 

Chris Giles

New member
Yep, those are the ones. White balance was set on the camera via a xrite passport.

Even though the daylight was most probably around 5500-6000k I didn't expect to see a green cast?
 

Kirk Candlish

New member
Fluorescents have a 'discontinuous spectrum' with green wavelength spikes. Ironically the Passport would cause them to show their 'true' green.

In the studio if they're your only light source, that's why you don't see them.
 

Chris Giles

New member
What should I do to counteract this? I thought it would be a simple case of matching the colour temperatures. Which I thought I was doing :(
 

fotografz

Well-known member
What should I do to counteract this? I thought it would be a simple case of matching the colour temperatures. Which I thought I was doing :(
Hard to tell where you were shooting, but it also may simply be "environmental" color cast when outdoors. In natural settings you get the green from the surrounding reflected light off trees/bushes etc.

Depending on the strength of the lights (contineuous lighting is usually much weaker than strobes), the more natural light mix with the artificial lighting, the more it'll be present. Fluorescence green spike and and use of the passport may be intensifying it.

Next time it happens, turn the lights off and just shoot a properly exposed, manually white-balanced ambient shot and see if the green reflected cast is still there in any way.

-Marc
 
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