Hi,
I was playing around yesterday and suddenly had the idea to try blending different white balances of the same picture to achieve that “warm lights/cold shadows” effect.
So I made these two in RT:
Then I blended them using Luminance masks in Gimp and got this:
It surely isn’t the perfect picture, but I like how it worked out.
What do you think?
Cheers
Stephan
I like this, the possibilities are endless! Being a novice using GIMP can you tell me how you used luminosity masks to blend two photos? Thanks
There’s an excellent tutorial (plus a script for Gimp) by PatDavid:
http://blog.patdavid.net/2013/11/getting-around-in-gimp-luminosity-masks.html
For this one I used only one inverted L mask (you will understand once you read the tutorial) on the warmer picture, which was on top.
It is one of my top requests for the local editing tool (under construction in RawTherapee) to be able to change the white balance of an area, for precisely that effect. I love it.
Oh, wow, we are getting a local editing tool? Awesome!
Thanks for the nice words. After posting this I was actually thinking on using this technique on your last PlayRaw. 
Go for it!
In case you are interested, next major PhotoFlow release will have a WB tool that works as an adjustment layer, with optional opacity mask to control the region where the effect is applied…
Here I played with @Morgan_Hardwood’s latest PlayRAW, giving the light coming from the top-right a cooler temperature to achieve a “night feel”:
This is the corresponding mask that I applied to the additional WB layer:
Oh, interesting…so now I’ll have to have a look at photoflow…
So many great tools out there…
I have been playing around some more with this technique and found old some early morning cityscapes, where I think it works nicely.
Here’s the automatic white balance out of RT or what I called the “cold” picture:
I love the blues, the sky and the darker areas, but the lights are too cold. I remember them warmer. After all those lights they use in germany to illuminate old buildings are really orange. So I made one with the camera’s white balance, the so called “warm” picture:
Here i love the warm lights but i do not like that basically everything has an orange tint. So I mixed them both in Gimp using Luminance masks again, warm for the lights, cold for the shadows:
i think it works really well for this picture.
It’s worth getting to grips with layer masks as well. While they are usually formed with brushes they can also be a mix of luminosity masks and brush work. The best advice on brush use for this sort of thing is usually to be bold rather than finicky.
Pat David has a tutorial on these too. They can be extremely useful for all sorts of things even selective sharpening to avoid bringing up noise - selective anything really.
http://blog.patdavid.net/2011/10/getting-around-in-gimp-layer-masks.html
