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kyuzo
05-16-2012, 10:45 AM
I've thought this would be handy a while ago, but now I'm doing a simple bit of compositing within lightwave, I could REALLY make use of a node that has a colour input, controls to adjust the levels of the red, green and blue channels, and a colour output.

Does anyone know if such a node exists?

I've managed a long-winded workaround, splitting the colour channel into the output of three seperate gradients, before combining them again with a make colour node, but it's hardly an intuitive workflow.

Any suggestions?

Derek

raw-m
05-16-2012, 12:55 PM
Any use?

http://forums.newtek.com/showthread.php?t=117574

kyuzo
05-17-2012, 06:02 AM
Cheers raw-m,

Yep, that does the job. Maybe not as user friendly as what I had in mind, but it works perfectly well.

Thanks.

gerardstrada
11-19-2012, 06:41 PM
Cheers raw-m,

Yep, that does the job. Maybe not as user friendly as what I had in mind, but it works perfectly well.

Thanks.

Some people may find Curves-type filters more user friendly than levels filter and vice versa. It depends on the tasks, I guess. Several of the primary color corrections in these samples were made with DP Curve Filter:

http://forums.newtek.com/showthread.php?124415-Post-process-tone-mapping-tutorials&p=1206402&viewfull=1#post1206402

The samples in the Spinquad link are 4 years old but if I remember well the last sample was re-made entirely with just DP Curve Filter and d&w Simple Colour Correction. Very handy.
Maybe another way to mimic PS levels filter would be with a setup like this:

http://s18.postimage.org/ndxqp78bt/levels_Ns_U.gif

SG_CCNode or d&w Simple Colour Corrector or Aurora's Gamma Correction node can be used for gamma correction, too.



Gerardo