White balance

[glitch]

Does anyone know of any software other than PictoColor's iCorrect EditLab Pro that allows you to take multiple 'neutral' areas for white-balancing during post-processing?

As far as I'm aware, both Photoshop and Lightroom only work from a single reference point?

 

[AliB]

Yes they do but they also have a really neat trick of doing the whole lot as a batch.

If you set a shot up and use a grey card you simply apply that correction in ACR to the whole set and it makes it a breeze

And if it's somewhere you shoot regularly you could save all the settings as a preset. Whoosh! There goes the workflow

 

[DiddyDave]

Yes they do but they also have a really neat trick of doing the whole lot as a batch.

If you set a shot up and use a grey card you simply apply that correction in ACR to the whole set and it makes it a breeze

And if it's somewhere you shoot regularly you could save all the settings as a preset. Whoosh! There goes the workflow

Except... my pc makes more of a whirrrr noise than a whoosh - do you have a Mac ???



DD

 

[glitch]

Good points, well made. That's actually something else to consider so I'm glad you brought it up. Speaking of the grey card, someone recommended using a small credit-card size version of the GretagMacBeth colour chart. I guess in a way that's the same theory?

Back to the software, I was just wondering why none of the 'major' editing suites offered the same level of control as the software I'd linked to in the OP. I only happened across the name of it in a magazine that's about two years old and couldn't quite understand why it hadn't been made a feature of the editing suites we're using now.

9 times out of 10 it's not a problem, but having the option to select multiple target neutrals for colour-balancing would seem like a sensible route to take. Just a bit surprised it's not already a feature of Photoshop or Lightroom.

 

[keith.l]

You can do it manually in Photoshop by using the colour sampler tool. You use that to drop, say, three samplers on the image - one each in a neutral shadow, midtone and highlight. Then you open the info window which will show the RGB values at each sampler position. Then the tricky bit - you create one or more curves layers so that each sampler reads equal values for R, G and B. You usually need to adjust the individual R,G and B curves, not just the master.

Not sure how the automated software works. If you click in multiple points on an image, each point could have a different colour cast. So to fix it you need localised adjustments. I guess it must do something along the lines of the manual curves method. Or maybe it just takes an average of all the points and corrects for that.

 

[AliB]

Except... my pc makes more of a whirrrr noise than a whoosh - do you have a Mac ???



DD

Nope, mine kind of grinds, spits a bit, backfires and generally refuses to do what it's told. Definately male

 

[ricky1980]

You can do it manually in Photoshop by using the colour sampler tool. You use that to drop, say, three samplers on the image - one each in a neutral shadow, midtone and highlight. Then you open the info window which will show the RGB values at each sampler position. Then the tricky bit - you create one or more curves layers so that each sampler reads equal values for R, G and B. You usually need to adjust the individual R,G and B curves, not just the master.

sounds complicated. let me get this right, you setup 3 curves for each of the channels and you try to match the R G B value for the 3 tones exactly the same via the curves?

 

[keith.l]

It's not as complicated as it sounds. I find the tricky part is identifying areas that you know are genuinely neutral. But if you do have those, as glitch's example, this technique is good.

You drag a sampler into each area that you know to be neutral, then you create the curves layer(s) to remove any casts. You don't have to use multiple curves layers but sometimes it's easier. The example below shows how it works. The samplers are not in neutral areas, but it shows the technique.

In the first image, I've dragged in three samplers which should be (but aren't) in neutral areas. Then it's just a case of going into each of the RGB curves and fiddling with them until the RGB values are equal. You then just go on and repeat the process on the other samplers.

The second screen cap shows the three points with the values made even, all done on one curves layer.

Obviously, I don't faff around like that with every image, but occasionally it's useful. And it's quite quick to do. You can do it with just a couple of points. And you don't have to make everything exactly equal. Sometimes it just gives you a pointer: I remembered after playing around with this photo the guy's skin actually was a lot darker than it shows up in the original.

 

[glitch]

Now that is very useful indeed. I'll be giving that a crack later.

Thanks for taking the time to explain in such detail, keith. Much obliged.

 

[keith.l]

No worries. You're welcome.