Dan Margulis Applied Color Theory
CMYK Techniques on RGB Devices
Date: Mon, 10 Nov 2003 16:01:48 -0000
From: "joao_g_fonseca"
Subject: CMYK on RGB only devices
Hello,
My congratulations to Mr. Dan Margulis for his excellent book.
I want to print my images in a photo lab, but I understand that their printers accept only RGB files (they use lasers to expose photographic paper).
How can I use CMYK special techniques (for example sharpening the cyan and black channels with faces)? Won't I loose information when going back to RGB?
Regards,
Joao Fonseca
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Date: Mon, 10 Nov 2003 12:01:52 -0500
From: Jim Rich
Subject: Re: CMYK on RGB only devices
Joao,
If you have CMYK images that need to be printed on an RGB device, it sounds like you don1t have any choice in the matter. But at some point the CMYK images will get converted to RGB. The only question is where in the imaging process do you want to do that. Did you scan the images or were they supplied to you from a vendor?
You can still use channels, but instead of using the Cyan or Black channel you might have to choose other channels (such as Red ) if you want to use that method to sharpen fleshtones.
Jim Rich
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Date: Mon, 10 Nov 2003 09:59:45 -0700
From:Andrew Rodney
Subject: Re: CMYK on RGB only devices
on 11/10/03 9:01 AM, joao_g_fonseca wrote:
Won't I loose information when going back to RGB?
You will indeed. The most serious is that these RGB printers have a significantly larger color gamut than CMYK so while you1ll get a print, you1re not using all the available color you could have if you started with an RGB file, converted it to RGB for these printers (using an RGB output profile), then converted to CMYK for whatever CMYK process you need from there.
Best to start with a fairly wide gamut RGB file, then repurpose it as often as you need for each and every output device you want to print to. CMYK is an output colorspace so it1s by that definition optimized for a single output device. That1s not the case with an RGB file either in a capture space or better, an RGB Working Space.
Andrew Rodney
http://www.imagingrevue.com/
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Date: Mon, 10 Nov 2003 17:33:43 -0000
From: "joao_g_fonseca"
Subject: Re: CMYK on RGB only devices
Hello,
My images are RGB, but I may want to use techniques that work better in CMYK. For example:
-Sharpening the cyan and black channels to avoid over-sharpening skin imperfections. I find that sharpening the red channel only isn't so effective.
-Handling critical shadow detail.
-Contrast enhancement on the weak color (when the weak color is C, M or Y).
I feel that if I can't eventually correct my images in CMYK, I'm only using only 6 out of 10 possible channels.
Regards,
Joao Fonseca
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Date: Mon, 10 Nov 2003 11:31:13 -0700
From:Andrew Rodney
Subject: Re: Re: CMYK on RGB only devices
Global sharpening of any single channel can be a bit brutal. I prefer to make complex masks using the image itself and then run Photoshop's USM. This way, you can easily protect smooth areas as well as darker regions that usually have more noise and shouldn't be sharpened. Takes a bit more time but worth it. There are a number of technique for doing this which usually involve finding the best of the RGB channels to convert to Grayscale, then using something like Find Edges, blurring and inverting. You end up with a very complex mask that only sharpens edges so skin is protected. You can also use blending to control what degree of sharpening is done in highlights or shadows (you can do more sharpening in all tones while protecting delicate highlights from blowing out and protecting shadows.
An interesting article about sharpening that is an eye opener is from Bruce Fraser:
http://www.pixelgenius.com/sharpener/why.html
The article was just on Creative Pro's site as well.
Andrew Rodney
http://www.imagingrevue.com/
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Date: Mon, 10 Nov 2003 11:12:01 -0800
From: Lee Varis
Subject: Re: Re: CMYK on RGB only devices
If you're only concerned with sharpening techniques you can apply these CMYK techniques and still maintain the full color gamut of your original RGB. (1.) First, duplicate the RGB document.(2) convert this duplicate to CMYK (3) perform your CMYK sharpening techniques (4) hold down "shift" key and drag the CMYK duplicate back onto the original RGB file the CMYK duplicate will be converted to RGB and placed as a layer on top of your original RGB. (5) Change the layer apply mode to luminosity the effects of the sharpening will be applied but the original color gamut will be preserved.
Its important to note that any color effects will not be preserved this way.
regards,
Lee Varis
http://www.varis.com
888-964-0024
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Date: Mon, 10 Nov 2003 12:21:24 -0800 (PST)
From: John Robinson
Subject: Re: CMYK special techniques
Going from LAB to RGB isn't a big color deal. The big deal is going from RGB to CMYK. Going from RGB to CMYK effects blues, oranges, and pastels badly.
Do your special techniques in RGB. All filters are available in RGB mode.
Going from RGB to CMYK will reduce the gama (color range) in your image, but going from CMYK to RGB will make no change in your image gama. Your image won't gain any color, but simply exist in a larger gama. It will be an RGB file, but it will be as colorful as the CMYK version.
John Robinson
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Date: Mon, 10 Nov 2003 22:09:53 -0000
From: "kuhammer2004"
Subject: Re: CMYK on RGB only devices
Also to what's posted try this one for rgb images.
http: //groups.yahoo.com/group/colortheory/message/5022
If you have "the book". There are other ways of sharpening images for output.
John Opitz
p.s. also, do a search for "sharpening" on the color theory groups. This newsgroup will not steer you wrong.
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Date: Mon, 10 Nov 2003 17:29:49 -0600
From: "Fred Drury"
Subject: Re: CMYK on RGB only devices
Hi Joao ...
If you look on pg 340 of Dan's Professional Photoshop, 4th edition you will see: "if you have to output in RGB, but would like to do certain work in CMYK, think false profile .... such a profile is included on the CD". Hopefully you have that edition and the CD. I use Dan's 'rgbk' color space all the time for just the purpose you ask about. Use 'Convert to Profile' to go from Adobe RGB (1998) to rgbk and once you have completed your color correction and sharpening moves don't forget to 'Convert to Profile' back to Adobe RBG (1998) before saving the file for printing.
Best of luck,
Fred Drury (aka fotofred2)
Markland Imaging
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Date: Tue, 11 Nov 2003 01:04:58 EST
From: Dan Margulis
Subject: Re: Re: CMYK on RGB only devices
Going RGB>CMYK>RGB isn't especially difficult, particularly if you're using a wide-gamut CMYK profile such as the ones developed by Mike Russell or the ones mentioned by Fred Drury. However, it's inconvenient. As time has gone on several new tools have developed that reduce the number of images that really benefit from this extra conversion.
Enhancing shadow has been a notorious weakness of RGB. Photoshop CS has introduced a new RGB command that will help out a great deal, Shadow/Highlight. With it, non-expert RGB users can easily open up shadows in ways that were too difficult for them before. Even experts will find that this makes life easier. CMYK now will only be needed for images where the shadow detail is supremely important to the image, and even then, a preliminary move with Shadow/Highlight in RGB appears to help the process out.
There are reasonably effective workarounds for the other areas Joao mentions. It's correct that RGB is the weakest of the three sharpening spaces. But, for images where one would like to sharpen the black in CMYK, a similar result can be gotten in RGB by loading luminosity as a selection (Command-Option-~ on an English-language Mac keyboard), inverting the selection (Command-Option-I) and then sharpening either in RGB or, preferably, in the L channel of LAB.
Similarly, attacking the weak color in CMYK can often be emulated by doing RGB blending in luminosity mode. So, the number of cases where I'd recommend leaving RGB for CMYK (assuming an RGB destination) are small. If there's super-critical shadow detail that's still best handled in the black channel of CMYK. If the image has several different interest objects that occupy different ranges, CMYK curves may get better results. Or, if you're deliberately trying to prevent bright colors from developing, it will be easier to do this in CMYK with a heavy GCR setting that will allow the black to muddy matters up.
Dan Margulis
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Date: Tue, 11 Nov 2003 08:36:58 -0800
From: Phil Lewis
Subject: Re: Re: CMYK on RGB only devices
Dan recently mentioned the below technique:
There are reasonably effective workarounds for the other areas Joao mentions. It's correct that RGB is the weakest of the three sharpening spaces. But, for images where one would like to sharpen the black in CMYK, a similar result can be gotten in RGB by loading luminosity as a selection (Command-Option-~ on an English-language Mac keyboard), inverting the selection (Command-Option-I) and then sharpening either in RGB or, preferably, in the L channel of LAB.
My question: how do you load luminosity as a selection. If a pic is open and you choose Control-Option (I use a PC) nothing happens. Can you please be more specific about the first step "loading luminosity as a selection"?
Many thanks.........
Phil
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Date: Tue, 11 Nov 2003 11:42:39 -0800
From: Rick Gordon
Subject: Re: Re: CMYK on RGB only devices
I've done some experimentation with integrating CMYK edits affecting luminosity (such as sharpening) back into an RGB environment. What I'm finding is that the best re-integration is effected by the following workflow:
1) Duplicate the original RGB image, and convert to CMYK.
2) Perform your CMYK edits, such as cyan sharpening or black channel enhancement, etc.
3) Convert the edited CMYK duplicate to Lab.
4) Copy the Luminosity channel.
5) Duplicate or temporarily convert the original full-gamut RGB file to Lab.
6) Paste the Luminosity channel from the CMYK->Lab image into the Luminosity channel of the RGB->Lab image.
7) Convert the RGB->Lab image back to RGB.
I am seeing a visible difference between doing this and doing a Luminosity blend of the CMYK image (reconverted to RGB) onto the original RGB image.
Rick Gordon
--
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RICK GORDON
EMERALD VALLEY GRAPHICS AND CONSULTING
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Date: Wed, 12 Nov 2003 11:59:15 -0000
From: Stephen Marsh
Subject: Re: CMYK on RGB only devices
Rick Gordon wrote:
I am seeing a visible difference between doing this and doing a
Luminosity blend of the CMYK image (reconverted to RGB) onto the
original RGB image. <
I have understood that the luminosity blend is a simulation of L, rather than an on the fly mode change - which is why results can vary. If you have the time to see which is 'best', then try both moves. It may vary from image to image on which method one prefers - even though they are both attempting to do the same thing.
Stephen Marsh.
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Date: Wed, 12 Nov 2003 15:46:01 -0800
From: Mike Russell
Subject: Re: CMYK on RGB only devices
Rick Gordon wrote:
I am seeing a visible difference between doing this and doing a
Luminosity blend of the CMYK image (reconverted to RGB) onto the
original RGB image.
Stephen Marsh wrote:
I have understood that the luminosity blend is a simulation of L,
rather than an on the fly mode change - which is why results can
vary. If you have the time to see which is 'best', then try both
moves. It may vary from image to image on which method one prefers -
even though they are both attempting to do the same thing.
This matches my own conclusions.
Based on my own experiments, the Luminosity layer mode, as well as several other Photoshop operations, uses HSL space, not Lab space.
HSL is an algebraic space that does not rely on profiles, and among other things it assumes equal CMY values yield gray. Thus applying a CMYK image in luminosity mode results in a reddish cast.
Some of the other operations that exhibit this behavior are Hue/Sat, Variations, Selective Color, all the tool modes, the sponge tool, and Desaturate. I'm sure there are others.
Mike Russell
http://www.curvemeister.com
http://www.zocalo.net/~mgr
http://geigy.2y.net
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Date: Thu, 13 Nov 2003 14:45:41 EST
From: Dan Margulis
Subject: Re: Re: CMYK on RGB only devices
Phil Lewis writes,
My question: how do you load luminosity as a selection. If a pic is open
and you choose Control-Option (I use a PC) nothing happens. Can you please be
more specific about the first step "loading luminosity as a selection"?
Exactly as stated in the original post. Command-Option-~ (tilde) on a U.S. English Macintosh keyboard. Control-alt-~ is the Windows equivalent. If you are in LAB mode, Command-Option-1 will also work.
Dan Margulis
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Date: Fri, 14 Nov 2003 11:34:44 EST
From: Hal Silverman
Subject: Re: Re: CMYK on RGB only devices
In a message dated 11/13/03 7:49:50 PM, DMargulis writes:
Command-Option-~ (tilde)
What is the selection that is made based on?
Hal Silverman Studio, Inc.
6511B Basile Rowe
E. Syracuse, NY 13057
p. 315/434-9121
f. 315/437-6196
www.silvermanstudio.com
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Date: Fri, 14 Nov 2003 16:25:08 EST
From: Dan Margulis
Subject: Re: Re: CMYK on RGB only devices
Hal Silverman writes,
Command-Option-~ (tilde)
What is the selection that is made based on?
A grayscale version of the document, created internally and loaded as a selection without ever becoming visible to the user.
Dan Margulis
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Date: Fri, 14 Nov 2003 21:11:19 EST
From: Hal Silverman
Subject: Re: Re: CMYK on RGB only devices
Dan,
That's pretty interesting.
I actually use the that key command pretty frequently, making a new layer from the selection. I then apply a gaussian blur to that new layer, then a layer mask. I paint back in the diffusion in varying amounts. The effect resembles shooting split diffusion. I have also tried using individual channels.
Is there a way to alter what the command will select...perhaps wanting to select only highlight or shadow areas? I would imagine duplicating a layer and adjusting the contrast would alter the selection. But how would I be able to use that selection back on my original layer? I hope I am making sense!
Best regards, and thank you for all the great information.
Hal
Hal Silverman Studio, Inc.
6511B Basile Rowe
E. Syracuse, NY 13057
p. 315/434-9121
f. 315/437-6196
www.silvermanstudio.com
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Date: Sat, 15 Nov 2003 10:55:53 -0500
From: Terry Britton
Subject: Re: Luminosity Masks and layers (was CMYK on RGB only devices)
Hal,
I recently found another useful and *barely* documented keyboard shortcut (having no menu equivalent that I could find) to assist in making the layer used to create the luminosity mask (command/control-option/alt-tilde(~)) from reading the great article Andrew Rodney linked us to the other day by Bruce Fraser on Sharpening.
http://www.pixelgenius.com/sharpener/why.html
In it he mentions the 'Stamp' keyboard shortcut, which is pretty extreme - make a new, empty layer, turn on the eyeballs of all the layers you want merged into that new layer, and hit ALL the modifier keys (command-option and shift on Mac or CTRL-ALT-Shift on PC) and the letter 'E' on the keyboard. All the visible layers will be merged into the highlighted new layer while remaining individual layers themselves.
This is very useful for creating a 'composite' layer to create the luminosity mask from. I'm having students use it for lots of things. The new resulting layer can be used for lots of things - make luminosity selections and make into masks, blur, find edges or glowing edges to invert and copy and paste the layer into a new alpha channel to be used as a selection in sharpening (from the article above), make other wild masks and alpha channels for special uses - anywhere you've gone and created a dozen layers you want merged. The alternative I've been using, of creating a duplicate and merging layers, is also fine, but this does all the work in the same document, and I can save my work all at once to come back to the next day in one document. When done with the layer you've made this way, just chuck it! Or, keep it around!
Terry Britton
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Date: Sat, 15 Nov 2003 12:49:09 EST
From: Dan Margulis
Subject: Re: Re: CMYK on RGB only devices
Hal writes,
Is there a way to alter what the command will select...perhaps wanting to
select only highlight or shadow areas? I would imagine duplicating a layer
and adjusting the contrast would alter the selection. But how would I be able to
use that selection back on my original layer? I hope I am making sense!
First of all I would stress that over-selecting is the first refuge of the unholy, and that the more proficient one becomes with color the less selection one does. That said, it's sometimes needed, of course.
To operate on highlight only I prefer not to make a selection at all, but rather operate in the way I explained to John Ruttenberg earlier, with Blending Options. That is, if you're trying to add highlight detail simply, one way is to make a duplicate layer, put it in Multiply mode, then activate Blending Options, choose Blend If>Gray>Underlying Layer and move the left slider almost all the way to the right of the scale. Then split the slider with the Option key and move the left half back to the left to create a transition.
As for making a channel selection and then altering it and reloaded, this is a piece of cake. If you want, for example, you're in RGB and you want to load an altered version of the red channel as a mask, the procedure would be:
1) Command-Option-1 to load the first channel (red) as a selection.
2) Select: Save Selection, either to a new channel, or to a new document, doesn't matter.
3) Turn to that new document or channel, and make your alteration. Remember to blur the channel afterwards because such alterations often create overly sharp edges.
4) Return to the original document and Select: Load Selection. As long as the channel is part of the existing document, or if it is a new document it's still open, it will appear as an option.
Dan Margulis
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Date: Sat, 15 Nov 2003 22:46:42 -0000
From: Stephen Marsh
Subject: Re: Luminosity Masks and layers (was CMYK on RGB only devices)
I recently found another useful and *barely* documented keyboard
shortcut (having no menu equivalent that I could find) to assist in
making the layer used to create the luminosity mask
(command/control-option/alt-tilde(~)) from reading the great article
Andrew Rodney linked us to the other day by Bruce Fraser on Sharpening.
It is often mentioned by numerous users that the loading of the composite channel is poorly documented, I have heard this more than once. Just like the images colour channels (1/2/3/4) - the ~ tilde is also listed in the channels palette as an obvious keycut. It is not a big step to add the opt/alt key to the combo as this is found in the colour channels too.
It does seem to be 'hidden' [missing?] from HTML help, and I have not
checked the printed guide for more info.
Years ago I tested all this, if I remember correctly the ~tilde selection saved as an alpha is slightly different to the L channel of LAB (just like the B of HSB and the L of HSL are slightly different too).
In it he mentions the 'Stamp' keyboard shortcut,
I have heard the term stamp being used for this process from more than
one source - I can't recall if this was a legacy command term or just
a term that people use to describe the process.
The 'merge visible with duplicate' naming convention comes from the actions palette. This can also be done by holding down the opt/alt key when manually selecting the merge visible command, but as suggested the key combo of (opt/alt+shift+cmd/ctrl+N) [new layer] and (opt/alt+shift+cmd/ctrl+E)[stamped merged with duplicate] is good for
'power users'.
Stephen Marsh.
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Date: Sun, 16 Nov 2003 04:31:05 -0000
From: Dan Margulis
Subject: Re: Luminosity masks and layers
Stephen writes,
Years ago I tested all this, if I remember correctly the ~tilde selection
saved as an alpha is slightly different to the L channel of LAB (just
like the B of HSB and the L of HSL are slightly different too).
Curioser and curioser. No, as I said earlier, it's a grayscale conversion being loaded as a selection. But I've just played around a bit and discovered that it is not just a grayscale conversion being loaded, but one that's based on the current Color Settings. Thus, if Stephen and I are working on the same RGB file on two different machines, and we both have the same RGB working space loaded, and we both make a selection with Command-Option-tilde, we will get two different selections unless our grayscale workspaces are also the same.
I have a feeling this bears on what Mike Russell was saying earlier on strange behavior in layers in Luminosity mode. He reported that certain blends unexpectedly work better if done in the L of LAB rather than in Luminosity mode in RGB. This is similar to something I reported earlier this year, that, contrary to expectations, certain images appear to sharpen significantly better in the L channel of LAB than on a Luminosity layer in RGB. I offered a suggestion about why this might be (pertaining to the unusual lightness of the L channel) but now I am wondering whether there might be some other explanation.
I hope to have time to investigate this later this year but meanwhile if anybody else has any thoughts I'd be interested to hear them.
Dan Margulis
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Date: Sat, 15 Nov 2003 23:48:23 -0500
From: Jonathan Clymer
Subject: Re: modifying command/option/tilde (was CMYK on RGB only devices)
From: Hal Silverman
Is there a way to alter what the command will select...perhaps wanting to
select only highlight or shadow areas? I would imagine duplicating a layer and
adjusting the contrast would alter the selection. But how would I be able to
use that selection back on my original layer? I hope I am making sense!
Rather than alter the command itself, modify the resulting selection. If you want to select the highlights only, enter quick mask, then bring up the curves dialogue box and move the lower left anchor point to the right. If you want to select the shadows, enter quick mask, invert the mask (command/i), then bring up the curves dialogue box and as before, move the left anchor point to the right. Its much easier to see the results of the curve move if you make the RGB (or CMYK) channels invisible during the adjustment so that you only see the quick mask image.
Jonathan Clymer
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Date: Sun, 16 Nov 2003 11:14:19 -0000
From: Stephen Marsh
Subject: Re: Luminosity masks and layers
Curioser and curioser. No, as I said earlier, it's a grayscale conversion being
loaded as a selection.
Interesting Dan - I stand corrected, looks like my memory was not totally correct. <g> The L of LAB is rather different than the ~tilde, although when I tested the B of HSB and L of HSL they were more similar to the L of LAB than the ~ selection saved as an alpha.
But I've just played around a bit and discovered that it
is not just a grayscale conversion being loaded, but one that's based on the
current Color Settings. Thus, if Stephen and I are working on the same RGB
file on two different machines, and we both have the same RGB working
space loaded, and we both make a selection with Command-Option-
tilde, we will get two different selections unless our grayscale workspaces
are also the same.
This will need deeper exploration, this was not apparent with a quick test (unlike the previous).
Stephen Marsh.
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Date: Mon, 17 Nov 2003 00:29:32 +0200
From: Timo Kirves
Subject: Re: Re: modifying command/option/tilde
Claudio,
in Scandinavian keyboard, loading the luminosity mask goes with command-option-shift-accent (next left to backspace).
That might work with yours too.
greetings
Timo
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Date: Mon, 17 Nov 2003 06:41:25 EST
From: Dan Margulis
Subject: Re: Re: modifying command/option/tilde
Claudio writes,
Is there any alternative way to command+option+tilde for loading a
layer luminosity mask? In my Italian keyboard there is no tilde and
I can't find such information anywhere else...
Three ways:
1) Open the Channels palette and look at the top box (composite color). There should be a keyboard shortcut shown next to it (Command+tilde in the English version). Adding an Option to whatever is shown in the Italian version would probably work.
2) If that doesn't work, you can do it by opening the Channels palette and Command+click on the top (composite color) box.
3) If this is a continuing problem you could also put alternate keyboards into your menu bar. I forget how this is done but it must be easy because I set up my own Mac this way: one click next to the Finder icon and I can switch to a Spanish-language keyboard instantly. So, you could just switch the Macintosh to U.S. English while doing your Photoshop work and back to Italian afterward, and then the tilde would be accessible in the upper left-hand corner of the keyboard.
Dan Margulis
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Date: Mon, 17 Nov 2003 06:57:38 EST
From: Hal Silverman
Subject: Re: Luminosity Masks and layers...
Thank you to all, for your input. This list is certainly a wealth of knowledge.
Regards,
Hal
Hal Silverman Studio, Inc.
6511B Basile Rowe
E. Syracuse, NY 13057
p. 315/434-9121
f. 315/437-6196
www.silvermanstudio.com
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Date: Mon, 17 Nov 2003 16:16:40 +0200
From: claudio.corvino
Subject: Re: Re: modifying command/option/tilde
Dan,
Thank you. You are great. Which is your background?
--
Claudio
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Date: Mon, 17 Nov 2003 22:22:41 EST
From: JoeButts
Subject: Re: modifying command/option/tilde
I'm just curious.
REF: The Claw Technique (CMD/OPT/~ on the Mac or CNTRL/ALT/~ on the PC) or using the Channels and creating the Luminosity Mask by CMD-Clicking the RGB Channel or any of the individual Channels
How did someone ever discover this technique? Who found it? It's not in any of the Adobe manuals on PS -- is it?
I enjoy trivia and I think this would be a great bit of Photoshop trivia. "Trivia"? Luminosity masking like this is not trivial. It's a wonderful tool. Glad we've got it.
Joe Butts
Joe Butts Photography
(505) 388-2826
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Date: Tue, 18 Nov 2003 07:55:59 +0000
From: Shangara Singh
Subject: Re: modifying command/option/tilde
Joe
I haven't been able to find it if it is documented. That's not surprising, though. Reading between the lines, it seems the different departments do not communicate that well. How else do you explain the inconsistencies between ImageReady and Photoshop? They have been bundled together for some, what, 4-5 years? Also, the online documentation has been woefully inadequate and badly put together in the past (the Help file for Photoshop CS looks a lot more professional but I haven't looked at it as closely as I have at vs6/7).
Getting back to your shortcuts, the list in the Help file is very limited. I have seen more extensive lists in book or available for free on the Internet as PDF's. You can download one by Trevor Morris from here: http://user.fundy.net/morris/redirect.html?photoshop7.shtml
--/ Shangara Singh.
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Date: Wed, 19 Nov 2003 18:02:01 -0500
From: "Tara Marlowe"
Subject: Re: CMYK on RGB only devices
How can I use CMYK special techniques (for example sharpening the cyan
and black channels with faces)? Won't I loose information when going
back to RGB?
You could use the wide gamut CMYK space Dan has ont he disk that comes with his book version 4. if you converted to such alarge CMYK space then you would be able to get back to RGB without much loss.
Or you go to LAB from RGB, which is relatively painless and do your sharpening to the L channel.
Or you could work in RGB but set your Info palette to CMYK values. There are tons of cool sharpening techniques like using the high pass filter on a separate layer and set the to darken and paint in using layer mask or Unsharp aks and fade Luminosity under the Edit menu. Those are the ones I can think of right now. Dan Margulis and Bruce Fraser have written excellent articles on sharpening techniques.
Tara Marlowe
Digital Artist NYC
http://www.taramaqrlowe.com
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Date: Thu, 20 Nov 2003 07:36:10 EST
From: Dan Margulis
Subject: Re: Re: modifying command/option/tilde
Claudio writes,
Thank you. You are great. Which is your background?
Prepress and printing, and good literature and good music. Now, I spend most of my time teaching small groups of people how to make pictures look good. This week, I'm doing the second of two three-day advanced sessions (the first was last month) for persons who have already taken the first applied color theory course. I always learn a lot from such sessions and if anything good comes up, eventually this group will hear about it!
Dan Margulis
Adobe Photoshop training classes are taught in the US by Sterling Ledet & Associates, Inc.