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RGB to Lab/CMYK and back to RGB

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  #41  
Old 08-12-2011, 07:29 PM
RobertAsh RobertAsh is offline
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Re: RGB to Lab/CMYK and back to RGB

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Originally Posted by bakerser View Post
Genuinely OOC, what about the action which Jonas linked to doesn't work in your workflow?
What is OOC?

For me, encapsulating all the layers into one big smart object then converting color spaces (and being able to still work with the SO's adjustment layers) stopped working. No reason that I could see, it just didn't work anymore (only worked a couple of times anyway).
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  #42  
Old 08-12-2011, 07:31 PM
RobertAsh RobertAsh is offline
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Re: RGB to Lab/CMYK and back to RGB

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Originally Posted by kav View Post
I've tried to think of a good way to respond, but I guess I simply don't like this method.

Are you shooting raw? Do you have any files that you are able to show that exhibit these problems? I could probably show you better ways of dealing with these things.
I can't blame you, I don't like it either. But it worked for me when I needed it.

Yes, I shoot raw. I'll try to find some file for you from a more recent shoot that has skin tones that need correcting. I'm more consistent now with white-balancing my lights before shooting but there's one recent shoot that might be a good candidate.
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  #43  
Old 08-13-2011, 05:20 AM
bakerser bakerser is offline
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Re: RGB to Lab/CMYK and back to RGB

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Originally Posted by RobertAsh View Post
What is OOC?
Out Of Curiosity
Quote:
Originally Posted by RobertAsh View Post
For me, encapsulating all the layers into one big smart object then converting color spaces (and being able to still work with the SO's adjustment layers) stopped working. No reason that I could see, it just didn't work anymore (only worked a couple of times anyway).
I completely understand - except that that action didn't use Smart Objects or convert color spaces?
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Originally Posted by RobertAsh View Post
One question,though, is that on really detailed color wheels I've Googled up often CMY does not equal RGB, as CMY and RGB are not opposites along all 3 colors. Any insight on that? does that affect at all how the opposite curves work?
FWIW, having a color wheel which would 'appropriately' demonstrate this isn't likely to happen, at least not without specifically creating it for the purpose. Remember that they are theoretically opposite color models; not necessarily always opposite color hues (on which almost all color wheels are based). The hue opponency is a function of the color space vs of color mode / model.
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  #44  
Old 08-13-2011, 08:59 AM
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John Wheeler John Wheeler is offline
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Re: RGB to Lab/CMYK and back to RGB

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Originally Posted by RobertAsh View Post
For me, encapsulating all the layers into one big smart object then converting color spaces (and being able to still work with the SO's adjustment layers) stopped working. No reason that I could see, it just didn't work anymore (only worked a couple of times anyway).
Hi Robert
"Only worked a couple times anyway" That reminded me of a common phrase of test pilots as they walk away from the crashed test plane Hmmm, was it the plane or the pilot?

Not sure this was the issue yet here is a common problem with that technique:

If you group a bunch of layers and make them a Smart Object, then go to that Smart Object and change color modes (e.g. to CMYK) you are always given the option to flatten the layers or not. There are many circumstances where if you do not flatten the layers when changing color modes, that image will not be preserved at all and yield a totally different result. This is not an issue of the Smart Object, this is an issue of converting a stack of layers to another Color Mode whether in an SO or not.

Per my previous post, I stamp the layers before converting to a SO and from within the SO change to another Color Mode (as a single Layer). Then, all additional Layers added in the new Color Mode will work just fine. After saving the SO, what happens effectively is a stamped copy of the SO is created, converted back to the main objects Color Mode (as determined in Color Settings), and inserted back into the Main Documents Layer Stack.

Not sure that was your issue yet changing Color Modes and not flattening can be a big gotcha under many circumstances.

PS - And from one friend to another, if that is not your issue and if I ever buy a plane (never happen), please remind me not to loan it to you for a test spin
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  #45  
Old 08-13-2011, 09:52 AM
edgework edgework is offline
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Re: RGB to Lab/CMYK and back to RGB

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Originally Posted by RobertAsh View Post
One question,though, is that on really detailed color wheels I've Googled up often CMY does not equal RGB, as CMY and RGB are not opposites along all 3 colors. Any insight on that? does that affect at all how the opposite curves work?
One can find color wheels, grids and whatnot for any variety of end results. But for the issues under discussion here, there is no wiggle room, and not because it's my opinion; it's just the laws of physics.

Forget wheels: all you need is a six-pointed star. With C, M and Y on three equi-distant points, you will always find Red in between M and Y because Magenta and yellow make red. Green will always be between C and Y and Blue will always be between C and M. In that model, opposite Red you will always find Cyan, opposite Green you will always find Magenta and opposite Blue you will always find yellow. Either/ or, in all cases.
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