Any tips for handling colored walls and on camera flash?

Had my camera along to document an evening event. Usual set up: Canon 6d, 24-70, Speedlite - no off-camera gear, etc.. I am quite comfortable using bounce flash.
However, this event was in the green room. Green all over the place: walls, ceiling - even the floor had a green tint. The result predictably: all pictures have a very strong green tint that can not completely be compensated in post. Especially getting pleasant skin tones is very hard.

How do you deal with such situations? Any suggestion how to get better colors (except painting walls and moving the event...).

Shooting RAW helps a lot with getting that sort of ugly situation close to corrected. I think exposing to the right also helps a bit.

Never happened to me, so I am not the voice of experience ... but ...

I guess you bounced the flash. The bounced light of course would be green. So the red and blue channels were underexposed. You shot raw, right? That allows you to fix the white balance in post. But the red and green channels, depending on how badly they were underexposed, might have clipped or ended up with tons of noise.

So as George mentioned, ETTR might have helped maintain a decent signal level in the R and B channels. You could have tried shooting direct (no bounce), with a suitable modifier to soften the light a bit. If you had known about the green beforehand, you might have (OK, impractical suggestion) put a magenta filter on the flash or the lens, if you could get such a filter and it was the right color.

Archibald: You hit the nail on the head.
Here's the example without any color correction. Not a good picture, but it shows the room and the geen (tint).

Archibald wrote in post #18599231
Never happened to me, so I am not the voice of experience ... but ...

I guess you bounced the flash. The bounced light of course would be green. So the red and blue channels were underexposed. You shot raw, right? That allows you to fix the white balance in post. But the red and green channels, depending on how badly they were underexposed, might have clipped or ended up with tons of noise.

So as George mentioned, ETTR might have helped maintain a decent signal level in the R and B channels. You could have tried shooting direct (no bounce), with a suitable modifier to soften the light a bit. If you had known about the green beforehand, you might have (OK, impractical suggestion) put a magenta filter on the flash or the lens, if you could get such a filter and it was the right color.

I think a magenta filter would have gone a long way. Flash gels are highly underutilized, but man they are a life saver when you have color casts to contend with in the field. I always keep a set in my bag. A magenta filter may not have perfectly corrected the green color cast....but it would have gotten the colors a lot closer to correct and given a greater chance of correcting things in post.

Did you use a bounce card?

Color Checker along with a slight gel would help too.

If you bounce flash from colored walls there is always a limit. You won't get the same skin tones as if you would shoot with off-camera flashes and umbrellas.
With bounce flash I would first try to get the best colors as possible in camera so I would set custom WB with gray card.
After that I would do a shot or two of colorchecker passport standing right in the middle of that table.
You would stil have to do some color adjustments in RAW converter.

You have wicked mixed light sources. There is the green bounced light but also the overhead fluorescent light, and maybe some direct light from the flash. There is no practical way to correct that.

Archibald wrote in post #18599821
You have wicked mixed light sources. There is the green bounced light but also the overhead fluorescent light, and maybe some direct light from the flash. There is no practical way to correct that.

Underexpose the ambient to get rid of the color casts from the other light sources. From there you only need to correct the color cast coming from the bounced wall.

mystik610 wrote in post #18599823
Underexpose the ambient to get rid of the color casts from the other light sources. From there you only need to correct the color cast coming from the bounced wall.

Certainly. I should have said no practical way to correct that now.

mystik610 wrote in post #18599823
Underexpose the ambient to get rid of the color casts from the other light sources. From there you only need to correct the color cast coming from the bounced wall.

Really good idea! Will need to keep that in mind next time. It seems that strongly colored walls is all the rage here with our interior designers. They all over the place and I certainly will have a chance to use this technique. And I definitely need to have a look at gels.

drmaxx wrote in post #18599828
Really good idea! Will need to keep that in mind next time. It seems that strongly colored walls is all the rage here with our interior designers. They all over the place and I certainly will have a chance to use this technique. And I definitely need to have a look at gels.

Use gels only to try to correct light sources, but not to try to counteract 'contamination' of color walls. If you have a neutral reference target, it can provide you with a good reference for fixing in post processing. I just took a series of shots, with neutral reference, with daylight and then (underexposing ambient by -2EV) with flash unit bounce off ceiling with various tinted gels over the flash head to simulate bounce against various colored wall/ceiling.


Shot 1 is with daylight, shots 2,4,and 6 taken with various gels bounced off ceiling, then shots 3,5,and 7 are neutralized versions of 2, 4, 6 and 6 during post processing

drmaxx wrote in post #18599292
Archibald: You hit the nail on the head.
Here's the example without any color correction. Not a good picture, but it shows the room and the geen (tint).

Hosted photo: posted by drmaxx in
./showthread.php?p=185​99292&i=i233419334
forum: General Photography Talk

Here's an example of the issue this causes. This is the best correction I can get with white balance, but there is still unpleasant green in the shadows and behind the glasses.

Hosted photo: posted by drmaxx in
./showthread.php?p=185​99292&i=i225201273
forum: General Photography Talk

To show what you can accomplish simply with using a sampler tool (the eyedropper in many different photo editors)...simply sampled the paper plate just visible to the right of the plastic bottle of Coke

Archibald wrote in post #18599821
You have wicked mixed light sources. There is the green bounced light but also the overhead fluorescent light, and maybe some direct light from the flash. There is no practical way to correct that.

...which is precisely why I said to to try to correct via a gel over the flash. The chances of using the right value of gel to precisely balance even a single fluorescent tube makes it very difficult...there used to be literally a dozen different combinations of gel strengths to offset the many different fluorescent bulbs that might be installed at a location -- and then you had to also hope they did not MIX tubes in the fixtures, each having different color correction gel values.

Archibald wrote in post #18599824
Certainly. I should have said no practical way to correct that now.

Yet look at the results I have in shots 3, 5, and 7 in Post 12!