Photoshop Lab Color- P12 ppsx

The image of the younger woman mea- sures as having a slight red cast, on the rea- sonable assumption that both the hair and the background should be neutral. In glam- our photography like this, a warmer feel is often desired, so I suspect the photographer did this on purpose. Nevertheless, the recipe calls for taking it out. The man’s hair has a slight bias toward magenta, but the image’s midrange seems fine. Therefore, I lightened the darkest areas of the green channel with a curve. There appears to be no color problem with the older woman. So, we proceed to Step One of the recipe, applying the green channel of each to the composite image on a new layer set to Luminosity mode. The results are shown in Figure 16.11. As expected, all images have increased contrast, and are somewhat darker, which we’ll take care of later in LAB . You should be able to see the adjustment in the man’s hair color that occurred between Figures 16.9 and 16.11. And the color change in the younger woman is obvious, and disagreeable—mut- ing the red cast has made the skin too gray. Fortunately, working in LAB means never having to worry about tepid colors. Next comes the intermediate step of look- ing for strong reds. I see none in any of the three. On to Step Two, converting to LAB and flattening the images, and to Step Three, the creation of a duplicate layer for overlay blends to the A and B . The paths diverge here, because we have three sharply different complexions. As noted earlier, the lighter the complexion, the more it should favor use of the B ; the darker, the A . The three results of the overlay step are in Figure 16.12. They’re all intentionally too colorful, and all made with different over- lay percentages. Figure 16.8 Left, the original (Figure 16.1A) repeated for convenience. Right, the final sharpened version. AB Chapter 16. A Face Is Like a Canyon Page 9 Return to Table of Contents Chapter 16. A Face Is Like a Canyon Photoshop Lab Color: The Canyon Conundrum: And Other Adventures in The Most Powerful Colorspace By DAN MARGULIS ISBN: 0321356780 Publisher: Peachpit Press Prepared for NV Moorthy, Safari ID: moorthy@ceybank.com Print Publication Date: 2005/08/08 User number: 910771 Copyright 2007, Safari Books Online, LLC. This PDF is exclusively for your use in accordance with the Safari Terms of Service. No part of it may be reproduced or transmitted in any form by any means without the prior written permission for reprints and excerpts from the publisher. Redistribution or other use that violates the fair use priviledge under U.S. copyright laws (see 17 USC107) or that otherwise violates the Safari Terms of Service is strictly prohibited. • Light-skinned Caucasians, such as the older woman in this set and the earlier subject of Figure 16.1, generally need the yellow component of their flesh emphasized more than the ma- genta. These individuals often can be identified by their light hair and blue eyes. To make the version in Figure 16.12, I used overlay percentages of 100% in the B but only 75% in the A . • Moderate- to dark-skinned Cau- casians and other groups of similar skintone don’t require the sort of artifi- cial suntan we just manufactured. Some persons of Asian ancestry have skin darker than almost all Caucasians, but the younger woman shown here isn’t one of them. I used 100% overlays in both A and B channels. • In Caucasians with unusually dark 332 Chapter 16 Figure 16.9 Three original portrait files. Chapter 16. A Face Is Like a Canyon Page 10 Return to Table of Contents Chapter 16. A Face Is Like a Canyon Photoshop Lab Color: The Canyon Conundrum: And Other Adventures in The Most Powerful Colorspace By DAN MARGULIS ISBN: 0321356780 Publisher: Peachpit Press Prepared for NV Moorthy, Safari ID: moorthy@ceybank.com Print Publication Date: 2005/08/08 User number: 910771 Copyright 2007, Safari Books Online, LLC. This PDF is exclusively for your use in accordance with the Safari Terms of Service. No part of it may be reproduced or transmitted in any form by any means without the prior written permission for reprints and excerpts from the publisher. Redistribution or other use that violates the fair use priviledge under U.S. copyright laws (see 17 USC107) or that otherwise violates the Safari Terms of Service is strictly prohibited. skin or other individuals who are at least that dark, and particularly in African-Americans, excessive yellow in the fleshtone is objectionable. For the man pictured here, I reversed the ratio used for the older woman. I accentu- ated the magenta component of his skin more than the yellow, by using overlay opacities of 100% for the A and 75% for the B . Step Four consists of choosing how to split the difference between each of the bland versions of Figure 16.11, which are on the bottom layer, and the exuberantly saturated ones of Figure 16.12 on the top. For the young woman, I chose an opacity of 70%, which is to say, a lot closer to the colorful version than to the dull one. For the older A Face Is Like a Canyon 333 Figure 16.10 The same images after application of this chapter’s recipe. Chapter 16. A Face Is Like a Canyon Page 11 Return to Table of Contents Chapter 16. A Face Is Like a Canyon Photoshop Lab Color: The Canyon Conundrum: And Other Adventures in The Most Powerful Colorspace By DAN MARGULIS ISBN: 0321356780 Publisher: Peachpit Press Prepared for NV Moorthy, Safari ID: moorthy@ceybank.com Print Publication Date: 2005/08/08 User number: 910771 Copyright 2007, Safari Books Online, LLC. This PDF is exclusively for your use in accordance with the Safari Terms of Service. No part of it may be reproduced or transmitted in any form by any means without the prior written permission for reprints and excerpts from the publisher. Redistribution or other use that violates the fair use priviledge under U.S. copyright laws (see 17 USC107) or that otherwise violates the Safari Terms of Service is strictly prohibited. woman I went to 60%, and in view of the fact that it is supposed to be a picture of a businessperson and not a cooked lobster, only 45% for the man. What would your choices have been? From this point the steps are sub- stantially the same as shown earlier between Figures 16.6B and 16.8B. There is no need to rehash them here. In comparing the corrected versions of Figure 16.10 to the originals of Figure 16.9, look around the noses and chins. The greater depth stems from the original blend of the green channel in Luminosity mode, aided by the final curve applied to the L channel. To- gether, they are responsible for adding 334 Chapter 16 Figure 16.11 The green channel of the RGB originals has been applied to each composite image in Lumi- nosity mode, a step analogous to that shown in Figure 16.1B. The two right-hand images have had slight color adjustments prior to the luminosity blend. Chapter 16. A Face Is Like a Canyon Page 12 Return to Table of Contents Chapter 16. A Face Is Like a Canyon Photoshop Lab Color: The Canyon Conundrum: And Other Adventures in The Most Powerful Colorspace By DAN MARGULIS ISBN: 0321356780 Publisher: Peachpit Press Prepared for NV Moorthy, Safari ID: moorthy@ceybank.com Print Publication Date: 2005/08/08 User number: 910771 Copyright 2007, Safari Books Online, LLC. This PDF is exclusively for your use in accordance with the Safari Terms of Service. No part of it may be reproduced or transmitted in any form by any means without the prior written permission for reprints and excerpts from the publisher. Redistribution or other use that violates the fair use priviledge under U.S. copyright laws (see 17 USC107) or that otherwise violates the Safari Terms of Service is strictly prohibited. contrast in a recipe that, being LAB - oriented, keeps color and detail in sep- arate compartments. For the color part of the equation, see how the lips in all three individuals break away from the rest of the face in the corrected version far more than in the original. That’s the AB influence, something that can’t be duplicated by increasing saturation in other colorspaces. But Here Is the Best Part As LAB is the choice of those who are young at heart, it is appropriate that we end our discussion with the face A Face Is Like a Canyon 335 Figure 16.12 The images shown in Figure 16.11 have been converted to LAB , where, on a separate layer, the A and B channels were applied to themselves in Overlay mode. These versions are intentionally made too colorful so that a final choice of color can be made by finding a suitable point between each version and its counterpart in Figure 16.11. Chapter 16. A Face Is Like a Canyon Page 13 Return to Table of Contents Chapter 16. A Face Is Like a Canyon Photoshop Lab Color: The Canyon Conundrum: And Other Adventures in The Most Powerful Colorspace By DAN MARGULIS ISBN: 0321356780 Publisher: Peachpit Press Prepared for NV Moorthy, Safari ID: moorthy@ceybank.com Print Publication Date: 2005/08/08 User number: 910771 Copyright 2007, Safari Books Online, LLC. This PDF is exclusively for your use in accordance with the Safari Terms of Service. No part of it may be reproduced or transmitted in any form by any means without the prior written permission for reprints and excerpts from the publisher. Redistribution or other use that violates the fair use priviledge under U.S. copyright laws (see 17 USC107) or that otherwise violates the Safari Terms of Service is strictly prohibited. of a child. And, as LAB is the choice of the creative, it is appropriate to recall that recipes lay an important foundation but that superior dishes are prepared by those who can improvise. A smiling little girl surrounded by flowers can make almost any photographer look good. Indeed, Figure 16.13 is passable just the way it is. A characteristic of those who use LAB , however, is the gnawing suspicion that the original image is never good enough. The recipe we’ve been working with so far won’t work here, at least not without some preparation. It assumes normally lit subjects. This one isn’t. The sun is too strong. The right side of the face is heavily in shadow, while the left side is almost gone. Applying the green channel in Luminosity mode, as we have been doing, darkens the face, which would be good for the left side but fatal for the right. As we near the end of a book about LAB technique, the bag of tricks that we can reach into has become rather large. It would be absurd to pretend that there’s one right way to handle this picture, particularly since, as you’re about to see, the first time I tried it I screwed it up. One day I’ll give it out as a class exercise and see what others can make of it. For now, it might be useful to explain what I see in this original and what I think the choices are. First, the image is full of bright colors, which constitute an argument against using LAB . Anything that intensifies the flowers or the sweater will drive them out of the gamut of whatever our final output space is. As against that, in LAB , unlike RGB ,it’s a snap to exclude those areas from any other work being done on the image. Nothing is remotely close to being as A –positive as the flowers are. I can enhance the girl’s face on one layer, and if it wrecks the flowers I can Figure 16.13 The harsh sunlight coming in from the left side is an obstacle to the use of this chapter’s recipe. Chapter 16. A Face Is Like a Canyon Page 14 Return to Table of Contents Chapter 16. A Face Is Like a Canyon Photoshop Lab Color: The Canyon Conundrum: And Other Adventures in The Most Powerful Colorspace By DAN MARGULIS ISBN: 0321356780 Publisher: Peachpit Press Prepared for NV Moorthy, Safari ID: moorthy@ceybank.com Print Publication Date: 2005/08/08 User number: 910771 Copyright 2007, Safari Books Online, LLC. This PDF is exclusively for your use in accordance with the Safari Terms of Service. No part of it may be reproduced or transmitted in any form by any means without the prior written permission for reprints and excerpts from the publisher. Redistribution or other use that violates the fair use priviledge under U.S. copyright laws (see 17 USC107) or that otherwise violates the Safari Terms of Service is strictly prohibited. restore the originals with one sweep of a Blending Options slider. The image reminds me of two that ap- peared in the last chapter. Another species of purple flowers graced Figure 15.5, but they were the most important part of that picture. Here the girl is the focus of attention. How- ever, darkening the flowers and lightening the greenery worked well there. Blending an inverted copy of the A channel into the L in Overlay mode is therefore an option. Second, the combination of sun and shade in the face is reminiscent of the hunter of Figure 15.6. Unfortunately, the light parts of the girl’s face are much lighter than the man’s were. Any effort to lighten the dark parts of the face by blending with the A or B will wipe out the light parts. The Shadow/Highlight command, nor- mally quite potent, was ineffective against the hunter image, and can’t be expected to do well here either. We need a trick that will lighten the right side of the face (and, if pos- sible, the hair) while darkening the left side. Chapter 15 hinted at how. Overlay mode uses 50% gray as a dividing line. Where the overlaying image is lighter than 50%, it lightens the underlying one; where darker, it darkens. If we can find a channel where the two halves of the face fall on different sides of 50%, we should be able to make a significant improvement. Once the file gets to LAB (it starts in RGB , of course), we won’t find such a channel. In both A and B the entire face is positive because even in the darkest areas, it’s still a distinctly warm color. The L would also not be of use. It’s lighter than any RGB channel, so both halves of the face would probably be lighter than 50% gray. A Face Is Like a Canyon 337 Figure 16.14 Left, the blue channel of Figure 16.13. Right, the channel is blurred and inverted to prepare for a blend. BA Chapter 16. A Face Is Like a Canyon Page 15 Return to Table of Contents Chapter 16. A Face Is Like a Canyon Photoshop Lab Color: The Canyon Conundrum: And Other Adventures in The Most Powerful Colorspace By DAN MARGULIS ISBN: 0321356780 Publisher: Peachpit Press Prepared for NV Moorthy, Safari ID: moorthy@ceybank.com Print Publication Date: 2005/08/08 User number: 910771 Copyright 2007, Safari Books Online, LLC. This PDF is exclusively for your use in accordance with the Safari Terms of Service. No part of it may be reproduced or transmitted in any form by any means without the prior written permission for reprints and excerpts from the publisher. Redistribution or other use that violates the fair use priviledge under U.S. copyright laws (see 17 USC107) or that otherwise violates the Safari Terms of Service is strictly prohibited. Unless there’s some major color balance problem, any face, any race, any age, any page, any pose, any nose will be lightest in the red channel and darkest in the blue. The blue (Figure 16.14A), is where we should look because that’s the one where the right side of the face is certain to be darkest. The left side can’t possibly be close to 50% in any channel. I propose to overlay this blue channel onto the composite image. It needs to be blurred heavily first, as otherwise there will be weird artifacting in sharply defined areas such as the eyes and eyebrows. Therefore, we’ll need a separate copy of the blue, as we can’t afford to destroy the existing copy. Also, during the overlay the channel needs to be inverted. Otherwise, the light areas will get even lighter and the dark ones will plug. In real life, we check the Invert box in the Apply Image dialog when popping the blurred blue into the composite. For ease of visualizing what is about to happen, how- ever, I’ve inverted Figure 16.14B already. Once you get your bearings—it’s cropped exactly as Figure 16.4A is—you can see that it is about to darken the left half of the face plus the flowers, and lighten almost everything else. Applying it to the composite RGB of Figure 16.13 in Overlay mode, 100% opacity, pro- duces Figure 16.15. The face and hair are greatly improved. The background is interesting, possibly better and possibly not. Bad things have happened to the sweater and the red ribbon. 338 Chapter 16 Figure 16.15 Figure 16.14B, a separate channel, is applied to Figure 16.13, Overlay mode, on a new layer. Chapter 16. A Face Is Like a Canyon Page 16 Return to Table of Contents Chapter 16. A Face Is Like a Canyon Photoshop Lab Color: The Canyon Conundrum: And Other Adventures in The Most Powerful Colorspace By DAN MARGULIS ISBN: 0321356780 Publisher: Peachpit Press Prepared for NV Moorthy, Safari ID: moorthy@ceybank.com Print Publication Date: 2005/08/08 User number: 910771 Copyright 2007, Safari Books Online, LLC. This PDF is exclusively for your use in accordance with the Safari Terms of Service. No part of it may be reproduced or transmitted in any form by any means without the prior written permission for reprints and excerpts from the publisher. Redistribution or other use that violates the fair use priviledge under U.S. copyright laws (see 17 USC107) or that otherwise violates the Safari Terms of Service is strictly prohibited. There isn’t a convenient way to revert to the original sweater in RGB . Try to exclude things that are dark in the blue channel, as the sweater is, and you get the hair also. Exclude things that are light in the red, and kiss the left half of the face goodbye. If the file were in LAB , the problem would go away, because nothing is nearly as B –positive as the sweater and the ribbon are. The flowers are magenta, not red; they’re actually B –negative. The face and leaves are B –positive, but far less so than the sweater. When I first prepared this part of the chapter, I fell into a trap right here. Seduced by the great improvement in color between Figures 16.13 and 16.15, I moved briskly and stupidly into LAB so as to exclude the sweater and ribbon there with layer Blending Options. We have spent almost 350 pages learning that LAB is the best way to enhance color. Blending in Overlay mode in RGB is one of the worst. That it accidentally produced many good colors to go along with the ones that it wrecked should not have blinded me to the principle that overly gray colors are an utter, complete, total, and absolute non-issue when LAB is right around the corner. I should have (and I did, the second time around, having wasted about a day preparing these pages with an inferior method) changed the layering mode to Luminosity while I was still in RGB , producing Figure 16.16A. It’s grayer than it was, but it retains the excellent detail that the overlay manufactured in Figure 16.15. Moreover, its new green channel—Figure 16.16B—is eminently suitable for further blending. The recipe is back on track. We’re at Step One. You Have a Head Start On a new layer, I applied Figure 16.16B to Figure 16.16A in Normal mode, changed layer mode to Luminosity, and then trashed it because it looked terrible. It had darkened the face, appropriately Figure 16.16 Top, the layer is changed to Luminosity mode, restoring the color of Figure 16.13. Bottom, the green channel of the top version is now suit- able for further blending. A B Chapter 16. A Face Is Like a Canyon Page 17 Return to Table of Contents Chapter 16. A Face Is Like a Canyon Photoshop Lab Color: The Canyon Conundrum: And Other Adventures in The Most Powerful Colorspace By DAN MARGULIS ISBN: 0321356780 Publisher: Peachpit Press Prepared for NV Moorthy, Safari ID: moorthy@ceybank.com Print Publication Date: 2005/08/08 User number: 910771 Copyright 2007, Safari Books Online, LLC. This PDF is exclusively for your use in accordance with the Safari Terms of Service. No part of it may be reproduced or transmitted in any form by any means without the prior written permission for reprints and excerpts from the publisher. Redistribution or other use that violates the fair use priviledge under U.S. copyright laws (see 17 USC107) or that otherwise violates the Safari Terms of Service is strictly prohibited. enough, but it had disagreeably weakened the leaves and the sweater, both of which are light in the green channel. I therefore redid the layer, this time applying Figure 16.16B in Darken mode, pre- venting anything from getting lighter and producing Figure 16.17A. The recipe calls for checking for dark reds and purples, which this image has in abundance, and for taking them out of the mix by using the Blending Options slider to exclude things that are dark in the green channel. While that method works, a more easily controllable one is available, one that permits me to disallow the darkening of the flowers only partially, something I would like to do. By going to Step Two of the recipe, converting to LAB without flattening the file first, not only do I get slightly better color, but I can take advantage of the ability to isolate colored objects in Blending Op- tions. To make Figure 16.17B, I used two sliders, both of which I split by Option–clicking to create a zone of transition where Photoshop would average the two layers rather than choosing one or the other. The L channel slider restores Figure 16.16A fully in the hair, which is very dark, and partially in the red ribbon, sweater, and darkest areas of the face. There is no impact on the leaves, which are identical on both layers, thanks to the darken-only blend I used to make Figure 16.16A. The second slider is intended to catch the flowers. They are so strongly magenta-as-opposed-to-green that you might instinctively reach for the A sliders to deal with them. That would be a mistake. You could definitely isolate the most colorful areas of the flowers, which are far more A –positive than Figure 16.17 Top, Figure 16.16B is applied, Darken mode, to a new layer of Figure 16.16A, set to Overlay mode. Below, the file is converted to LAB without flattening, and portions of the top layer are excluded with layer Blending Options. A B Chapter 16. A Face Is Like a Canyon Page 18 Return to Table of Contents Chapter 16. A Face Is Like a Canyon Photoshop Lab Color: The Canyon Conundrum: And Other Adventures in The Most Powerful Colorspace By DAN MARGULIS ISBN: 0321356780 Publisher: Peachpit Press Prepared for NV Moorthy, Safari ID: moorthy@ceybank.com Print Publication Date: 2005/08/08 User number: 910771 Copyright 2007, Safari Books Online, LLC. This PDF is exclusively for your use in accordance with the Safari Terms of Service. No part of it may be reproduced or transmitted in any form by any means without the prior written permission for reprints and excerpts from the publisher. Redistribution or other use that violates the fair use priviledge under U.S. copyright laws (see 17 USC107) or that otherwise violates the Safari Terms of Service is strictly prohibited. [...]... theVeryYoung at Heart LAB is often characterized as a desperation strategy best left for use in disastrously defective images Not true Every original in this chapter is first-rate—until you look at how it was improved These improvements could not have come about without LAB However, unlike most of the examples in the rest of the book, they couldn’t have come about entirely in LAB, either In this last... have come about entirely in LAB, either In this last performance, fittingly, LAB played a supporting role—an important one, for sure, but subordinate to the star of the show, which was the overlay blend and reversion of Figures 16.15 and 16.16, which can’t be duplicated in LAB as far as I know It’s easy to appreciate how powerful LAB can be, but we shouldn’t ignore its limitations It makes massive color... characteristics that play into LAB s strengths We end with faces, another strong point Or, better put, another facet of the same strong point Faces and canyons present similar issues A person’s flesh, like a canyon’s walls, falls in a short darkness range, ideal for exploitation in the L channel Also, our last exercise was full of brilliant Chapter 16 A Face Is Like a Canyon Photoshop Lab Color: The Canyon Conundrum:... the Shadow/Highlight command And if you now realize why LAB in combination with RGB , let it be said—handles faces extremely well, then you have solved the canyon conundrum * * * Before you set out to perfect the techniques developed in this book, and to search for LAB solutions that are as yet undiscovered, we’ll close with another illustration of LAB s flexibility, its power to let different people do... Dan Margulis’s final version, after the application of the LAB curves shown at right It wasn’t all that long ago that we were facing a real rainbow, in Figure 11 3 The conclusion then was the same as now: look to the colorspace that has a homefield advantage LAB is where the rainbow sleeps, waiting for us to rouse it Fourth, Save and Close Some LAB techniques are both easy and effective: the Man from... chapter has revealed, I’m still struggling with some of the complexities that arise when LAB meets Photoshop I had to redo the image of the little girl, and I would certainly have done this last image differently had I reviewed Lee’s approach first Many of the examples in this book are second tries as well I do grasp LAB s incredible potential and, I think, most of the basic ways to use it But with disturbing... the way, we can widen or narrow Apply Image, again with the top layer’s L as the transition zone to make the flowers target, but using the underlying L as source Chapter 16 A Face Is Like a Canyon Photoshop Lab Color: The Canyon Conundrum: And Other Adventures in The Most Prepared for NV Moorthy, Safari ID: moorthy@ceybank.com Powerful Colorspace By DAN MARGULIS ISBN: 0321356780 Publisher: Peachpit Press... swirling patterns in the rock The original digital image was provided by one of the country’s leading commercial photographers, Lee Varis Lee, who is no slouch at LAB correction himself, uses this image as an instructional tool, not about LAB proper, but about the The Tilt Toward Yellow B–negative (more blue than yellow) objects are comparatively rare, skies excepted The B channel is therefore usually... indicates If a picture is properly color-balanced, you might think that the average color would be a gray—0A0B Not true As I’ve never seen a study of the subject, I analyzed about a billion pixels myself Not in this chapter, of course—close-ups of faces are very positive in both A and B But I grabbed all the corrected (so as not to be influenced by inadvertent casts), uncropped LAB images from Chapters 12,... in such trivia, Figure 16.17 would have won the most A–positive award, in spite of the presence of so many green, A–negative leaves Its mean pixel value is 14A9B Chapter 16 A Face Is Like a Canyon Photoshop Lab Color: The Canyon Conundrum: And Other Adventures in The Most Prepared for NV Moorthy, Safari ID: moorthy@ceybank.com Powerful Colorspace By DAN MARGULIS ISBN: 0321356780 Publisher: Peachpit Press . controllable one is available, one that permits me to disallow the darkening of the flowers only partially, something I would like to do. By going to Step Two of the recipe, converting to LAB without. come about without LAB . However, unlike most of the examples in the rest of the book, they couldn’t have come about entirely in LAB , either. In this last performance, fittingly, LAB played a supporting. the same as now: look to the color- space that has a home- field advantage. LAB is where the rainbow sleeps, waiting for us to rouse it. Fourth, Save and Close Some LAB techniques are both easy