Advanced white balance issue.

I shot some interior photos before the renovation. Using natural light for everything except for the bathroom.. as there was NO light.

As a result, the white balance is off. But using the eyedropper to fix doesn't give me good results.
Is there a way to have the bathroom photo look the same as the kitchen? The wood 'should' be the same colour.

What sort of lighting did you have in the bathroom? Also what did you use for the WB dropper? It looks to me as if you have the tint slider too far to the magenta side. I would try pulling that back over to the left to reduce the magenta and add some green. many artificial light sources these days seem to have quite significant chunks of the spectrum missing, which can make getting a good WB virtually impossible, because those wavelengths of light are simply missing. I've not seen anything like this from that cause, but it could be aggravating a badly set tint slider. Sometimes the auto selection does just miss for some unkown reason, so also maybe try a different spot for you WB selection.

Alan

You probably have to edit the per-channel black level. For example, your shadow tones in the bathroom shot have a magenta-ish cast. To eliminate that cast in the shadows, you need to .... [fill in the blank!] This can happen at low exposure levels where not a lot of info lives in the original exposure and you are boosting exposure. Also, noise can cause this color shifting as well. The edit may need to be applied as a local adjustment so it does not creep into the properly rendered areas of the image.

Can you post the raw file of rate bathroom shot (via Dropbox, etc.) for use to take a shot at addressing the issue?

kirk

Interesting info. I thought I did play with the tint slider, but I'll experiment again. I was using the eyedropper in LR.

kirkt; Are you saying that the WB might not be linear from light to dark? That's pretty interesting.

My guess is that it's fluorescent light and a high shutter speed, so you only got a partial cycle of the fluorescent flicker?

I might try the "skin tones by the numbers" technique, using a bit of the wood in the kitchen photo to create a reference to what your ratios SHOULD be, and a similar piece of wood in the bathroom as your target.

https://www.youtube.co​m/watch?v=4_wXx1Ng5ZY

I used a Curves Adjustment Layer masked to the wood. Pretty much what Nathan posted. I took a sample RGB reading from the kitchen pic and dropped a sample point on similar wood in the bathroom. Adjusted the RGB values to match. Masked to just the woodwork.

Dan Kearley wrote in post #17893465
...

kirkt; Are you saying that the WB might not be linear from light to dark? That's pretty interesting.

Take a look at this article:

http://www.clarkvision​.com …es/canon.raw.pr​ocessing1/

When the WB is applied during raw conversion, the black level offsets can get scaled such that the low end of the histogram has a WB shift. If you boost this area of the histogram to reveal it in the image, then you can see this artifact. You can address this as discussed in the article - see if it is the root of the problem for you, and see if the methodology in the article helps resolve the cast.

If you are not shooting with a Canon camera, then maybe something else is going on ....

kirk

wow.

i'd say you have some kind of camera or file problem.

This thread illustrates the immense value of simply including a neutral grey card in the scene as a reference for white balance and for density! Pull it out of the scene for the 'real shot'.

.

This doesn't look like a white balance (color temperature) problem to me.
Rather, it looks like a tint problem.

.

Was this shot raw, or is this a JPG only result from camera? If so, what do you have set for a picture style?

I also have to say that I completely misinterpreted the original post - I though that the bathroom shot was shot with natural light but there was very little of it. Never mind! My bad, i totally screwed the pooch on this one. (I could not figure out how you got such a noise-free image!).

Duh.

Anyway, if you have the raw file to upload somewhere so we can take a look it may be worth it.

kirk

Thanks for this interesting conversation. I realize I left out a vital(?) detail though. I'm using LR/enfuse to merge 3 different exposures of each image. (I obviously didn't need it in the bathroom, but anyway)

Now, the 3 source images that feed LREnfuse are all with the same WB settings... So I don't know exactly what's going on yet. But Correcting the WB of one of these source images is way easier than with this merged one. So I assume it's part of the problem.

This plugin works great without much fiddling for the most part though.

DThompson, thanks for that description. I might experiment doing it that way for fun.