Warning and Disclaimer This book is designed to provide information about Photoshop channels. Every effort has been made to make this book as complete . The Photoshop Channels Book by Scott Kelby. Read online, or download in secure PDF format. "Author Scott Kelby (Editor-in-Chief of Photoshop User magazine) shows you how to unlock the power of Photoshop's channels and really start using Photoshop.
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Start by choosing Calculations from the Image menu if you want the full scoop on the Calculations dialog, turn to page in the chapter on converting to black and white, the Calculations tutorial, and once you read that it will all become clear. So, all you have to do here is choose one of the two Alpha channels under Source 1 in this case, Blue copy , then choose the other channel Red copy under Source 2.
This new channel is a combination of your Red copy and Blue copy channels. Now it's time for cleanup you knew that was coming, right? See all those gray areas in the corners?
Well, they have to go remember, we want our masks to be solid black on solid white. At this point anyway. Keep in mind to stay away from the edges of your subject. If you have to get near the edges to remove some gray in those areas, use that "change the brush blend mode to Overlay" trick you learned in the previous tutorial, so you don't mess with the edges.
Now, get to itget rid of all those gray areas, until you have a solid white background, and a solid black subject. Control-I to Invert your channel. Now, click the Load Channel as Selection button as shown to load this mask as a selection you can see the selection loaded in the channel shown here.
Now, we're at that point againyou can drag her onto a different background, or press Command-J PC: Control-J to put her up on her own layer, then delete the Background layer and drag in a new background. Well, you do if you read the previous tutorial. Anyway, here she is, but there's a problem.
The problem is that since we selected her off a white background, you can see some little white areas known as edge fringe around some parts of her hair. This sounds like a bad problem, but usually the fix is really easy. Now, I really don't have to say this, but I'm going to, so forgive me. What do you do if the image you're selecting is on a black background? That's right, you choose Remove Black Matte.
Okay, Mr. Smarty Pants, what do you do if it's not from a white or black background? You punt. Okay, actually, you choose Defringe instead, set to 1 pixel. In other words, the lighting on her looks too warm to be taken on that cold blue background.
If that's the case, you might want to add a Photo Filter from the Create New Adjustment Layer pop-up menu at the bottom of the Layers palette so the lighting on her looks right.
By the way, before you add that adjustment layer, Command-click PC: Control-click on her layer thumbnail to put a selection around her first, or your Photo Filter will cool down the background, too. They're some of the oldest tricks in the book, right? And because of that you probably wish that at the top of the Channels palette there was a channel blend mode pop-up menu, so you could do the same thing with channels.
For example, if you were trying to make a mask from a Contrast channel, and you needed your subject to be darker, you could just go to the top of the Channels palette and choose Multiply. Ahhh, if it were only that easy.
Well, believe it or not, you can get the same blending effect with channels, and it's almost as easy as blend modes in fact, it uses the same blend modes. So, how do you get this pop-up menu? You use Apply Image. Think of it as "layer blend modes for channels," and you're about to see how easy it is to use them to make your masking jobs easier. In the example shown here, we have two versions of the same image. The image on the left is the original grayscale image, and in the image on the right, we've simply duplicated the layer and changed the blend mode to Multiply.
See how much darker this Multiply layer made the image the bottom of the lily is even turning black? Now, let's see how to do the same exact thing, but with channels. First find the Contrast channel, then duplicate that channel in this case, it was the Blue channel, so duplicate that channel. Now, we'd like this duplicate to be darker so we can make a channel mask from it.
To do that, go under the Image menu and choose Apply Image this is the tool that lets us get the same blending effect that we got in the first step using layers. When the dialog appears, choose the channel you want to multiply in this case, it's the Blue copy , then choose your Blending mode Multiply from the pop-up menu.
See how the channel now looks just like the Multiply layer? Now, click OK. If your channel still needs to be darker, just go back to Apply Image again, and use Multiply mode again here's the lily after I used Apply Image, set to Multiply mode, three times in a row. As you can see, the mask is almost completeit would take just a few paint strokes in black on the channel to finish things off.
Now, what do you do if you need to make something lighter?
In Apply Image, instead of choosing Multiply you'd choose Screen just like you would using layers. That's itnow you know the trick for getting layer blend modes to use on your channelsit's done by using Apply Image.
Thus far in this chapter, there's been plenty of contrast between the background and the object the first flower project had a light background behind it, and in the previous project, the nurse was on a white background, etc. So, what do you do? You create the contrast yourself. You use two different channel tricks to add more contrast, but you do it without damaging the photo. You're basically going to add contrast temporarily, just long enough to serve your masking purposes.
Then you're going to remove this temporary contrast and return to the original look of the photo, and in the process, you've built yourself a pretty tasty little mask.
Especially, since we get to employ a new channel trick or two along the way. So, here's the image and once again, you can download this same photo to practice along with from the book's companion website at www. You can see where the problem will behow do you separate that dark hair from the already dark background? Channels, of course. You knew that, right? Thought so. Well, the Green and Blue channels won't do us any goodthey're as dark, or darker than the full-color imagebut the Red channel shown here has some hope.
In fact, it's the only channel of the three in this photo that shows any separation between her hair and the background. I know what you're thinking, "If only there were more contrast between her hair and that dark gray background. Well, I guess it depends on how you do it. If you use a Levels or Curves adjustment layer, we could temporarily add in that extra contrast and separation we need.
That way the Red channel would have more contrast. Then we duplicate that Red channel while it has more contrast, and later trash the adjustment layer so our photo looks normal again. It's a brilliant plan and it just might be crazy enough to work. So, add a Levels or Curves adjustment layer from the Layer menu whichever you're more comfortable with and increase the midtones.
I used Curves here, clicked on the center of the curve and dragged upward to greatly open the midtones and lighten the gray background considerably. Look how much lighter the background looks now, and how much more contrast there is between her hair and the background. We created contrast on our custom channel where there really was none. And although the color photo looks overly saturated because of the adjustment layer, when we remove it later on in the process, the photo will return to its original saturation.
What you're going to do here is apply your Red copy channel to itself. This will make the background even lighter, while still keeping her hair fairly dark, getting you closer to an easy mask job. We do this applying a channel to itself by using the Apply Image command. Go under the Image menu and choose Apply Image.
When the dialog appears, for Channel choose Red copy your duplicate channel , and then in the Blending section choose Screen, so it's blended even lighter you see an onscreen preview as you go, as shown here. Now, we're going to make her hair even darker, and the background lighter yet.
Control-L] , and drag the left Shadow slider to the right to darken in the edges of her hair as shown here , then drag the right Highlight slider to the left to lighten the background. Don't drag too far in either direction or it will start to damage the edges of her hair, so keep an eye on that as you're dragging.
When it looks similar to the one shown here, click OK. Get the Brush tool B , press X to set your Foreground color to black, then start painting over the inside of her hair, and over her face, but rememberdon't get near the outside edges of her hair.
You can paint right over the interior highlights in her hair, just don't get near the outside edges we need to keep as much of them intact as possible. This will help keep you from accidentally painting off her hair and onto the gray background.
You still have to be careful, but painting in Soft Light over black, with that light gray background behind her, will help keep the spillover to a minimum. Also, you might have to paint over areas more than once in this mode. Now, filling in her shoulders and hands with black will be pretty easyyou can make a standard selection instead of a fancy channels trick. You can use any tool you'd like, but I'd recommend the Pen tool P , because of the smooth selections it makes.
Click the Pen tool once, then move your cursor farther along her shoulder, right over her fingers, and click again playing connect the dots until a path is drawn around her lower shoulders like the one shown here. Control-Enter to turn your path into a selection. Then, press Option-Delete PC: Alt-Backspace to fill the selection with black as shown here. Now you can press Command-D PC: You can still see some gaps in her neck, and where the fingers were on the left side, so in the next step you'll simply paint over those places.
The little gray triangle on the lower left side of her neck is actually the space between her fingers, so don't paint over that area. Keep painting until she's all filled in with blackjust remember to stay away from the edges of her hair. This lets you see that although the white parts of your mask look pretty good, the black background of this Alpha channel isn't really quite black yet. It's more of a really dark gray, especially near the corners, so take the brush and paint in black over those areas until the corners are solid black.
Again, steer clear of the edges of her hair. Of course, your image still looks way too contrasty because of that adjustment layer we added early on in this project to add extra contrast. Now, press Command-C PC: Control-C to Copy the photo into memory. Control-V to Paste the image onto your background. Notice how you were able to maintain the hair edge detail?
Thank the mask for that. But there's another way. It's quite a popular method, and one that you will either fall in love with and want to use all the time, or you'll just use it on special occasions, when you feel you need it, but either way we have to learn it. It's called Quick Mask, and it's essentially a temporary Alpha channel so, although it works similarly to an Alpha channel, once you load your selection, its job is done, and nothing is saved to your Channels palette.
So, besides being "quick," the other advantage is that you make your selection by painting using Photoshop's brush tools. That's right, you enter Quick Mask mode, you paint over the area you want to become a selection, and when you return to Standard mode it becomes one.
Quick Mask is ideal when you have an object with soft edges all around, because you can make your selection with a soft-edged brush. It's also ideal when you have an object that has some soft edges and some well-defined or hard edges like the project you're about to tackle.
Her body can be selected with a standard mask or selection tool, but her wings, with their soft edges and, even worse, the motion blurring the wing farthest away from the camera, will need some serious help.
I'll bet you're wondering how long it took to find a hummingbird hovering in front of a gray background. It took a while. Honestly, that's not what I was looking forI was just trying to find a hummingbird, but while searching on iStockphoto. But we can make our job easier by doing a little selecting work first on the hard edges or well-defined areas with the standard selection tools.
Although I used the Pen tool, you can choose any selection tool you're comfortable with the Lasso would work fine, as would the Magnetic Lasso.
So, go ahead and make a selection of the bird's body as shown here. When you enter Quick Mask mode, the masked areas the areas that are protected appear in a red tint. The areas that are selected appear clear. That's why the body of the hummingbird appears clear here. See how this relates to a regular Alpha channel, where the black area would be the masked area, and the white area would be where your selected area would be?
This freaks a lot of people out who aren't comfortable with the idea of painting away red to make a selection.
They'd rather that the background was clear, and the area they want selected would then appear in red instead it actually makes more sense, unless you have a background in traditional prepress. If you're one of those people and you know who you are , double-click on the Quick Mask icon at the bottom of the Toolbar, and when the Options appear, where it says Color Indicates choose Selected Areas, and click OK.
As you paint in black , it paints in a red tint. When you switch back to Standard mode, those red tinted areas will become your selection. Now, at least you know how they both work, and you can choose which method works best for you.
Once you make your choice, it is time to start making our soft-edged selection. First, set your Foreground color to white. Next, get the Brush tool B , and choose a medium-sized, soft-edged brush from the Brush Picker as shown here. By the way, we're going to go with the default Color Indicates for this tutorial, so red areas are protected, and the clear areas will become your selection later on.
You can see that as you paint, the full-color image is revealed. As you get closer to the edges of your wings, you'll have to shrink the size of your brush a bit use the Left and Right Bracket keys on your keyboard to change brush sizes as you paint. What you're aiming to do here is paint away the dark red areas on the wings. When you work on the back wing the one with all the movement , use a larger brush, and let the outside edge of the round cursor touch up against the outside edge of the wing.
As you can see, the center of the circle is well within the wing, but the outer edge of your circular brush cursor paints away those soft areas of red where all the motion is. Remember, try to paint away all the dark red areas. If you accidentally paint too far past the wings, you can instantly repair the problem by pressing X to switch your Foreground color from white to black and painting over those mistake areas in black.
As you paint, they'll be masked protected again.
So, toggle back and forth between white to add to your selection , and black to paint in red and fix your mistakes as you need. Okay, so what do you do when you're trying to mask something that's on a red background?
Doesn't that red tint make it hard to see what's going on? That's why Adobe lets you change the color of the tint overlay. Just double-click on the Quick Mask icon to bring up the Quick Mask Options, then click on the red color swatch to choose a new colorone that contrasts better with your background. Once you return to Standard mode, the clear areas of your Quick Mask become a selection as shown here.
Now, if you're looking at this selection, you're probably thinking, "Hey, those wings don't look like they have a softedged selection. They just look rounded. Press Command-C PC: Control-C to Copy your selected area into memory. Control-V to Paste your hummingbird into your document as a layer. Since it's on its own layer, you can get the Move tool V and position it so it's right next to the flower, as shown here.
Notice the soft edges of the wings are perfectly intact. Of course, there's another problem, and that is the lighting on the hummingbird looks too blue or "too cold" for the background photo we added her to. This could be a dead giveaway that the two photos were collaged, so we'll go ahead and fix that in the next step.
Start by getting your selection of her back. Press-and-hold the Command key PC: Control key and click once on her layer thumbnail to reload the selection around her. Choose Yellow from the Filter pop-up menu, and increase the Density a bit until she looks more yellowish than blue as shown here. When it looks right to you, click OK, and this adds an adjustment layer to your Layers palette, with a built-in mask over the background, so only the hummingbird is affected.
But if you paste yours and find out that some of the gray background she used to be on came along with her, you might need to go back and shrink the selected area of your Quick Mask, then try again. Luckily, there are two filters that help you shrink your entire selected area called "choking the mask" or increase the size of your selected area, in case you didn't get all of the bird selected called "spreading the mask". To choke the mask shrink it , go under the Filter menu, under Other, and choose Minimum as shown here.
When the Minimum dialog appears, there's only one controla Radius slider. As you increase the number sliding to the right it shrinks your selected area. In the example shown here, with a radius of 3, you can see that the selected areas have shrunk, because dark red areas are appearing all the way around your hummingbird.
Those dark areas are choking your selection making it smaller. So, if you switched back to Standard mode now, your selection would be 3 pixels tighter in all the way around your hummingbird. We use this trick anytime we see background fringe when we paste a photo into another photo. In the example shown here, we've opened the Maximum filter found under the Filter menu, under Other and increased the Radius to 3.
See how there's now a gray border around the hummingbird? That's the gray background from the original photo which in this case, we don't want. However, if you pasted the photo onto the background, and the soft areas of the wings were clipped off and looked like hard edges, you might try using the Maximum filter.
This will expand your selected area, so those soft-edged wings might be included. So what if you want to save your temporary Quick Mask as an Alpha channel, so you can reload it at any time? Here's what to do: While you're still in Quick Mask mode, go to the Channels palette and you'll see your temporary Quick Mask channel you'll see "Quick Mask" appear in italics. Command-click PC: Control-click on the Quick Mask channel's thumbnail to load your Quick Mask as a selection, then click once on the Save Selection as Channel icon as shown here.
That's ityour new channel appears as Alpha 1, and you can drag your Quick Mask channel into the Trash. Now, see those small gray areas around the wings aren't channels normally just black and white? Those gray areas indicate soft edges. Gray is important in Alpha channels, because it determines visibility. For example, black areas are protected, and not seen. White areas will be seen, right? Want it to be more transparent? Let's test itclick on your Alpha channel, then bring up the Minimum filter.
Since Alpha channels don't have that red tint, the best way to see the effects of the Minimum filter is to click directly in the preview window, inside the Minimum filter itself. This gives you a before and afterwhen you click-and-hold on it, you'll see the before, then release to see the choked version. In the Layers palette, click on the hummingbird layer, then get the Lasso tool and draw a very loose selection that completely encompasses the wings as shown here.
Control-Shift-J to cut those wings off the hummingbird layer and put them up on their own separate layer. Now, to finish off, let's make the edge areas of the wings appear a little transparent so it picks up some of the color from the background, which helps the bird look like it was really on this background.
Change the layer blend mode from Normal to Darken. Now, take a look at the bottom edges of the wingsyou can see the background peeking through. If we just lowered the opacity, the solid areas of the wings would also appear transparent. By changing the mode to Darken, just the areas darker than her wings show through.
If you want to dig much deeper into this whole masking and compositing thing, there's a book that I highly recommend and the entire book is dedicated to just those two topics.
It is, hands-down, the best book on the topic ever, and it explores all the different techniques and tools used in making intricate selections and realistic composites. Trust me, you'll dig it. Press-and-hold the Alt key and click on the Quick Mask icon on the bottom right of the Toolbox.
Press-and-hold the Option key and click on the Quick Mask icon on the bottom right of the Toolbox. For new channels, to change from the Press-and-hold the Alt key white mask showing the selected area to and click on the Save showing the unselected area in the Selection as Channel icon Channels palette: Press-and-hold the Option key and click on the Save Selection as Channel icon at the bottom of the Channels palette.
To view an Alpha channel as a red tinted Click on the Eye icon next overlay while you're on any channel: Click on the Eye icon next to the Alpha channel you want to view as a red tinted overlay. When making masks, why we do we always seem to paint the person we're masking in black?
You won't alwayssome photos will work better by making the mask of the person or object you're trying to mask white, and the background black like when you're trying to mask a lighter object on a darker background. So, it just depends on the photo. When you're looking for the Contrast channel, if the object you want to mask has white edges already, then the decision has already been made for youfill the rest of the object with white, and make the background black.
In the image shown here, the subject has blond hair and she's posed on a darker background, so when we make our mask from a copy of the Red channel in this case , it's easier to paint her hair in white, and then make the background black. When I'm using Levels to darken the edges, what happens if I move the sliders too close together?
Two things: That's why, when using Levels to darken the edges, you really have to keep an eye on the edges of your image as you drag your sliders toward the center. If I have large areas of black or white to fill in, do I have to take the time to paint them in?
You can save a lot of time by using a two-prong approach: Use the Brush tool to paint near the edges of your object, but for everything else use the Lasso or Marquee tools, select as much of the area as you can, then fill your selection with either white or black whichever you need.
Why do I usually have to invert the mask before I load it as a selection? You only have to do that if your mask has a white background and black object or subject and often when making masks, that's the case. We invert before loading because if you load it as is, it selects the backgroundnot the object or subject because black conceals and white reveals. Look at the capture below, where we loaded the Alpha 1 as a selectionsee how the background is selected, and not the woman?
So, before we load our Alpha channel as a selection, we need our subject in white, and our background in blackthat's why we invert first. What's the difference between Calculations and the Apply Image command? Calculations lets you combine two separate channels to create an entirely new channel.
Apply Image takes one channel and applies it to an already existing channelno new channel is created. How come when I view my RGB Composite and my Alpha channel at the same time, everything has a red tint over it and can I change the tint color? It's because by default Photoshop displays the channel in the tint color of a traditional rubylith that's the red masking material we used to cut with an X-Acto knife to make masks back in "the old days". You can change the default tint color, and opacity, from the Channels palette's flyout menu by choosing Channel Options.
What's the fastest way to save your selection as an Alpha channel? If you have the Channels palette open, click on the Save Selection as Channel icon at the bottom.
If not, just Control-click PC: Right-click within your selected area and choose Save Selection from the contextual menu that appears. How do you turn a path into an Alpha channel?
Go to the Paths palette and click on the Load Path as a Selection icon at the bottom of the palette, then go under the Select menu and choose Save Selection.
That's itfrom path to channel. What's "the ol' Quick Mask and Feather trick"? Ahhhh, I knew that eventually you'd ask that. It's based on the fact that when you add a feather to a selection, you don't really know what the results of the feather will be how soft the edges will actually be until you make a deletion, and by then it's too lateif you don't like it, you have to start over.
So, the trick is this: Make your selection, then instead of going to Feather, click the Quick Mask icon first, then you can see your selection as a mask. Now you can apply a Gaussian Blur and see, right there, exactly how soft the edges of your selection will be when you return to Standard mode.
Pretty tricky, eh? And if you weren't, perhaps you are now?
See, that's the power of the written word it can take you to places you've never been, uncover mysterious new worlds, and expose you to harmful emissions that are normally reserved for visiting foreign dignitaries.
That aside, there is a legitimate reason for including both layer masks and adjustment layers in this book and it's not the fact that both have channel-like masks attached to them, if that's what you were thinking. Actually, I added it to make my publisher crazy. You see, before you write a book like this, you have to swear to your publisher, in a blood oath, that you won't write more pages than you originally agreed to I agreed to pages, tops.
The reason is that paper costs have skyrocketed for the past six years, so to guard against future cost increases, publishers buy enough paper now to lock in a price for the initial print run 37 copies at exactly pages per copy.
Well, once they do that, I feel due to power issues all authors share that I must turn in the book with at least 50 more pages than I swore in blood that I would.
It's little things like this that give us authors the strength to carry on. Well, one of the non-destructive editing methods uses a mask attached to your layer. So, you're never really erasing pixels, you're just hiding them or letting them show you're either concealing them or revealing them. Luckily, since you've already had some experience with how masks work, you'll be right at home with these "other" types of channels they're not really channels at all, but they act like them in many ways, so once you understand channels, using layer masks becomes almost second nature.
The girl my sweet, little niece Jenna is a little overexposed too light , but the background behind her is even more overexposed. Ideally, you'd darken the background quite a bit, and darken parts of her like her jacket and maybe her hair , but I'd pretty much leave her face as is. This is where layer masks come in really handy, because they can let you selectively "paint with light" so the image winds up being lit exposed just the way you want, right where you want it.
Control-J to duplicate the Background layer, and then change the layer blend mode to Multiply. This has a multiplying effect, which makes the entire photo darker, as you can see here. Now the background looks much better, but her face looks too dark, and even her coat and hair are a bit too dark, as well.
So, before we were overexposed too light , and now our subject is underexposed she's too dark. Next, we'll add a layer mask so we can have the best of both worlds. This adds what looks like a white Alpha channel to the right of your layer's thumbnail image as shown. At this point, it has no effect on the photo whatsoeverit's just sitting there waiting for you to do something. Directly under it is the original "better exposed" version of Jenna on the Background layer, right? Without a layer mask, we could just grab the Eraser tool E and erase over Jenna's face, revealing the better exposed version on the layer below.
The problem with doing that is, you're actually erasing pixelscutting a hole out of a photo. However, by adding a layer mask, you're only knocking a hole out of the masknot erasing her photo like painting in black on an Alpha channel , so you can always undo by painting in white. So, get the Brush tool B , make sure your Foreground color is set to black press X , paint over her face, and it reveals the lighter version. So, to try this other method, you have to first remove the layer mask we added in the last step.
To do that, click directly on the white layer mask thumbnail, and drag it directly to the Trash icon at the bottom of the Layers palette. This will bring up a dialog asking if you want to delete the layer mask or apply it.
In this case, you want to delete it so we can start over, so click the Delete button. By the way, clicking the Apply button makes the changes you just made using the layer mask permanent.
Step 6. You should still have the duplicate layer in Multiply mode in place, so the photo looks too dark, right? Next, press-and-hold the Option key PC: Alt key and click on the Add Layer Mask icon as shown here. This adds a layer mask to your layer. But if you look at the capture shown here, holding that key down before you clicked the Add Layer Mask icon does two things: The darker layer is still there, it's just hidden behind that black mask.
That's a good thing. So, grab the Brush tool, press X to set your Foreground color to white, and start painting over the background areas of your photo as shown here. As you paint in white, the background becomes darker, because you're revealing the darker version of the photothe one that's hidden behind that black mask.
Think of it this wayblack conceals the darker version of the photo, and white reveals it. It's easy to remember if you use the famous old saying "Black conceals; white reveals. Well, we fixed the background, but how do you fix her coat and hair "just a little?
If you want some areas a lot darker but not fully as dark as the multiplied version of the layer , you can increase the Opacity of the Brush tool. Remember how I said when you paint on a layer mask you're not erasing pixels? You're not damaging the image, instead it's like you're working on an Alpha channelyou're painting on a mask, not the original. So, if you ever want to see a glimpse of that mask you've been painting on, just press-and-hold the Option key PC: Alt key and click directly on the layer mask thumbnail as shown here.
This shows you just the layer mask itself. The black parts mask the darker version. Now, it's time for a warning. When you click on a photo's thumbnail like you just did , you target the photo itself. So if you paint now, it will paint directly on the photo itselfnot on the layer mask. To begin painting on the mask again revealing and concealing , you'll need to click on the layer mask thumbnail instead.
So, that's the basics. I use a similar technique for sharpening portraits, as you'll see at the end of the next tutorial. The reason for this tutorial is not just to teach you compositing because this really isn't a compositing book, it's a channels book , it's to show you other ways to edit a layer mask, which are more like what you're already getting used to with editing Alpha channels.
Plus, it gives us an opportunity to use gradients on our layer mask, so we're not just working with solid and fully transparent areas, because shades of gray give us smooth transitions between solid and transparent. Just a reminder, if you want to practice along with these same photos, you can download them from the book's companion website at www. Get the Move tool V and drag this photo on top of your background photo as shown here. It's on its own layer, so drag it a bit over to the right so it extends off the edge of the document basically, just position it like you see here.
You'll see a hard edge where the tachometer photo ends, and that's what we're going to work onsmoothly blending these two photos together so you don't see that hard edgejust a smooth, gradual blending of the two images. This adds a white layer mask, since when it comes to channels and masks a white channel shows everything. There's that saying again: That's why adding this layer mask doesn't affect the image at allthe white reveals the entire layer, so it looks just like it did before you applied the layer mask.
When it appears, double-click on the third gradientthe blackto-white gradientto choose it. Now, click the Gradient tool right on your image at the spot where you want your tachometer image to be completely transparent near the left edge of that photo , then drag to the right until you reach the spot where you want it to appear fully solid. I added a white arrow so you can see where I started, and in which direction I dragged from the left edge to near the right edge.
Remember, this layer mask was all white before, and you could see the entire photo, so the white areas in the gradient will still show the full photo.
However, as the gradient turns gray as it moves to the left, the parts of the tachometer under that light gray area will start to become transparent. As the gradient moves farther to the left, the grays get darker, and your tachometer becomes even more transparent.
When it reaches black, the parts of the tachometer under that area become completely transparent because black conceals. Now, if you want to edit your layer mask, it's simplegrab the Brush tool B , choose a soft-edged brush, press X to set your Foreground color to black, and start painting.
For example, if you look just below the bottom left side of the tachometer, you can see a faint knob. If you want that knob to disappear become fully transparent , just paint over it in black remember, painting in black conceals thingsso paint over that knob, and any other stray parts, like the oil gauge.
Then you simply press X to switch your Foreground color to white, and begin painting over the inside of the tachometer. As you paint, you're revealing the photo on that layer as shown here you're revealing more of that photo that was hidden under the black part of the gradient. Control-Alt-Z until your white brush strokes are undone that's the keyboard shortcut for multiple undos. For this particular composite, you actually want the tachometer to appear pretty transparent, like it was before painting in white.
Again, nothing happens when this white layer mask is added because come on now…everybody sing along "white reveals. The point you started at will become transparent, and the point you stop dragging at will be solid. If you want more of the gearshift visible, paint over those areas in white. If you want more transparency, paint on the right side of the gearshift in black, because black will conceal what's on that layer.
To finish things off, get the Move tool and drag the tachometer a little bit over to the right. Then, drag the gearshift a little bit over to the left, revealing more of the car in the center. Now that you get the idea of layer masks, want some more ideas on how to use them?
Then turn the page for four quick ideas. First, apply the Unsharp Mask filter to the Background layer, then duplicate the layer, and apply the same filter one or two more times, until it's too sharp. Then Optionclick PC: Alt-click the Add Layer Mask icon. This adds a black mask to the layer, which conceals the super-sharpened layer.
Now, get the Brush tool B , make sure your Foreground color is set to white, then paint over just the areas that need extra sharpening. For example, on portraits, paint over the eyes, maybe the eyebrows, and any jewelry. Control-Shift-U to remove the color from the top layer, making it a grayscale photo. Now, click the Add Layer Mask icon.
Get the Brush tool, press X to set your Foreground color to black, and paint over one part of the photo that you want to appear in full color. As you paint in black, the black-and-white layer is concealed and the color layer below it is revealed. If you make a mistake, just switch your Foreground color to white, and paint over the area where you messed up. Start by opening a color photo and duplicating the Background layer.
Control-Shift-U to remove the color from the top layer, making it a grayscale photo, and then add a layer mask. Grab the Gradient tool G , and drag a black-to-white gradient from left to right about halfway across your photo. It will now fade smoothly from black and white to color. Open a photo that has a window in it.
Make a selection around the window. Then open a photo of some clouds. Select All, then Copy it into memory. Go back to your window photo your selection should still be in place.
Go under the Edit menu and choose Paste Into, to paste your clouds into the window. When you do this a layer mask is automatically created, and you can paint right on this mask to make the opening larger or smaller. You can also click on the clouds thumbnail and use the Move tool V to move your clouds around inside the window.
What that means is basically this: Normally, when you want to adjust the contrast or color in a photo, you'd probably use either Levels or Curves, right? The problem with using these two is that any adjustment permanently changes the pixels in your photo. However, instead of applying them directly to your photo, you can apply them on the layer above your photo called an adjustment layer , which has four main advantages.
You can delete the adjustment layer at any time just like you would any other layer and any changes you applied with Curves or Levels will be gone right along with it. And most importantly, 4 each adjustment layer comes with its own mask just like a layer mask. Here's a quickie on how to put them to use. In this case, we're going to change the color of the man's shirt, but this technique works the same no matter which adjustment layer you choose. So, you'll also use this technique for selectively applying Curves and Levels adjustments, and things like that.
Now, look in the Layers palette and you'll see the adjustment layer and its mask channel, which is filled with white by default.
Since it's filled with white, the full effect is revealed, which makes the entire photo look blue. Alt-Backspace , which fills the adjustment layer's mask with black, because "black conceals," right? To make the blue version of the photo visible just where you want it on his shirt , switch your Foreground color to white, and begin painting over the shirt with the Brush tool as shown here.
Again, you can use the same principle with any adjustment layer. If instead you had used Curves and darkened the entire image, you could fill the mask with black to hide the darker version, then paint in white over just the areas you wanted to be darker. Photoshop has a special form of channels called spot channels for doing this exact thing, and a special file format for saving spot-color images so they separate correctly for printing on a printing press.
Spot colors are used for four main reasons: You have to jump through a few extra hoops to create spot-color jobs in Photoshop, and although it takes more time to create a spot-color job, it isn't very hardit's just sometimes a bit tedious. In this example, we're going to use an illustration because it makes a great example , but you can apply this same technique to a grayscale photo that you want to print in two or more spot colors.
Before we start, take a look up in the title bar of the image we have here, and you can see that it's in Grayscale mode. So, we're starting with a grayscale image, and we're going to add spot colors to it. So, your first step in any spot-color routine is to select the area you want to be your first spot color. Since the flame and outline are a solid color kind of a medium gray , you can use the Magic Wand tool W to select them by just clicking once anywhere inside the flame.
Once you do, the flame and outline will become selected as shown here. You can see there's just one channelyour Gray channel. From the palette's flyout menu choose New Spot Channel as shown here to bring up the New Spot Channel dialog spot colors are added as individual channels. This Solidity setting throws a lot of people because it's strictly to help you envision the final imageit doesn't affect the final output the plates that you're going to give the printer one bit. So, adjusting this setting doesn't hurt, or help, anything other than to make your image look better to you onscreen.
If you actually do want a non-solid color, you lower the Opacity of whatever tool you're using to create your line art. Again, this doesn't change the spot plate that's going to be generated when it comes time to make your spot-color separationsthis is strictly a setting for your visual amusement onlyyour printer's going to get nothing but solid black plates.
Now you can click OK, and you've applied your first spot color. Although you're seeing red onscreen, when you color separate this image later on , these red flames will come out on a printing plate as solid black, then the print shop will apply the exact ink color you specify in the file you'll do that later on as well. You can either name your channels with the PMS color they'll have when separated now actually, you'd do it in the previous step, when the New Spot Channel dialog was onscreen , or you can do it later, right before you go to output the file or anytime in between.
There is no big hairy rule about when you have to name your spot channelsthe only rule is, "Don't forget to name your spot channels before you separate the file," or your printer will throw a fit at the very least. Of course, you start by clicking back on the original Gray channel, then you put a selection around the next area that you want to be a different color again, you can use the Magic Wand on an easy solid-color image like this.
In this instance, we'll select the lighter part of the batter's helmet, then press-andhold the Shift key to add part of the bat as shown here. Once those areas are selected, you choose New Spot Channel from the flyout menu again as shown.
When you click OK, you'll see three channels in the Channels palette, your original Gray channel and two spot channels. Now, that's the process you'll repeat for adding additional colorsyou go back to the Gray channel, make a selection, create a new spot channel, pick the color for that area, and click OK.
Simple enough. However, we're going to run into a problem when we go to print this file. You see that red outline around the batter click on the Spot Color 1 channel, then click on the Eye icon next to the Spot Color 2 channel, so you can see the red outline by itself, as shown here?
Well, we put that flame and red outline into its own spot channel, which will be printed in red when this goes to press. The problem is, that flame and outline are also still on the Gray channel, as well.
See how the flame and stroke are still on the Gray channel, too? If we went to press right now, you'd wind up printing that solid red from the Spot Color 1 channel over the gray flame and outline from the Gray channel.
This creates a color that looks like solid mush. You're going to have to delete that flame and outline from the Gray channel in a process known as "knocking out. You start by going to the Spot Color 1 channel and clicking on the Load Channel as Selection button, at the bottom of the Channels palette, to load it as a selection.
While the selection of the flame and outline is still in place, switch to the Gray channel as shown and hit the Delete PC: Backspace key on your keyboard to delete or knock out those areas from the Gray channel.
Press Command-D PC: Now, the flame and outline are only on the red Spot Color 1 channel. See, I told you knocking out was simple. Okay, since you can handle knocking out, are you ready for trapping?
Good, because you're going to need it. That's because if the printing press is out of register by the slightest amount, there's a good chance that instead of your red butting perfectly up against the black outline of the batter, there will be a thin white gap between the two colors. This is the kind of thing that makes pressmen climb towers with high-powered rifles.
But you can fix this problem easily enough by going back to the red channel and spreading expanding it by just a tiny bit 1 pixel, in fact , so it overlaps the black we generally spread the lighter of the two colors. You can do this by going under the Filter menu, under Other, and choosing Minimum.
If you look closely, you'll see that running the Minimum filter grows the flame on all sides so it spreads into the black ink area, but also outward into the white background, as well.
That's why, for instances like this where there's only color on one side the inside of the stroked area , you can use Photoshop's Trap control instead. When you choose it while on the Gray channel it's at the bottom of the Image menu , it expands the batter outward only, filling the white gap, so it doesn't affect the size of the flame or outline. Now you can continue the process of selecting areas, and then choosing the colors you want for each plate.
At this point, you can see the default names for each spot color are still being used Spot Color 1, Spot Color 2, and so on. In the next step, we'll change them to names that make sense to the print shop where you'll be printing the job. In the U. You can also just double-click on a channel's thumbnail to bring up the Options dialog shown here and type in your PMS name here.
This naming is important because when you color separate the job, each plate will have the PMS number printed right on it. Go under the File menu and choose Save As. When you click Save, it brings up the DCS 2. I recommend the JPEG Preview, because it looks the best, and the addition file size-wise is very small. Next, I recommend choosing Single File with Color Composite so you only have one file to keep track of, instead of one file for every spot color, and it includes that preview we talked about a few moments ago.
Okay, you're good to goclick OK, the file is saved, and you're ready to import the file into your page layout application.
Well, it works pretty much the same way, with just a couple of exceptions. You start by selecting the area that you want to have a spot varnish in this case, put a selection around her jeans.
Then go to the Channels palette you can see the image is in CMYK mode, with four color channels , and choose New Spot Channel from the palette's flyout menu as shown here.
Don't do a knockout, because the varnish goes over the CMYK image, not in place of it, and don't worry about trapping, because it's a full-color image, not line art, so trapping is not a concern. You will need to save the file as a DCS 2. Right-click on the layer mask thumbnail and choose Delete Layer Mask from the contextual menu. Control-click on the layer mask thumbnail and choose Delete Layer Mask from the contextual menu. To temporarily disable a layer mask: Shift-click directly on the Shift-click directly on the layer mask thumbnail in the layer mask thumbnail in the Layers palette.
Layers palette. To see just the layer mask by itself: Alt-click directly on the Option-click directly on the layer mask thumbnail in the layer mask thumbnail in the Layers palette. To create an inverted layer mask a layer mask filled with black: Alt-click on the Add Layer Mask icon at the bottom of the Layers palette.
Option-click on the Add Layer Mask icon at the bottom of the Layers palette. To see the layer mask as a red rubylith overlay: Press the Backslash key. To jump to the layer mask thumbnail: To load the layer mask as a selection: Right-click the layer mask thumbnail and choose Layer Mask Options.
Control-click the layer mask thumbnail and choose Layer Mask Options. To invert the layer mask: Press Control-I. Press Command-I. To copy a layer mask from one layer to another: Alt-drag the layer mask thumbnail to the layer where you want it to appear. Option-drag the layer mask thumbnail to the layer where you want it to appear. To move a layer mask from one layer to another: Click-and-drag the layer mask thumbnail to the layer where you want it to appear.
To convert a layer mask into a channel: Control-click on the layer mask thumbnail to load it as a selection, then click the Save Selection as Channel icon at the bottom of the Channels palette. Command-click on the layer mask thumbnail to load it as a selection, then click the Save Selection as Channel icon at the bottom of the Channels palette. To unlink a layer and its layer mask: Click on the Link icon between the two thumbnails in the Layers palette. I went to paint on my layer mask, but it paints on my image instead.
What gives? At some point, you must have accidentally switched from the layer mask thumbnail to the image thumbnail. You should then see a dark dashed line around your layer mask thumbnail, letting you know the mask is selected in the image shown below, the dark dashed line appears around the layer thumbnail, not the layer mask thumbnail, so when you paint, it paints on the image instead.
How do you copy a layer mask from one layer to another? In Photoshop CS2, to move a layer mask from one layer to another, you just click directly on the mask's thumbnail and drag it onto the layer where you want it to appear. But this moves the mask, it doesn't make a copy. To make a copy appear on another layer, press-and-hold the Option key PC: Alt key , then drag the mask's thumbnail.
In previous versions of Photoshop, you first click on the layer where you want to copy the mask to, then you go to the layer where the layer mask is, click-and-drag the layer mask thumbnail onto the Add Layer Mask icon at the bottom of the Layers palette, and the mask is copied to the layer you first selected.
What if I painted in black on a layer mask and I've really messed up. Do I have to paint the whole layer over in white again? Alt-Backspace , which will fill your mask with white, so you can start over. I understand that the layer and layer mask are linked together, but is there a way to unlink them? There sure isgo to the Layers palette and click on the Link icon that appears between the layer thumbnail and the layer mask thumbnail to unlink the two.
To relink them, click that same space. Can you temporarily turn off the layer mask? Just Shift-click directly on the layer mask thumbnail. A large red X will appear across your layer mask thumbnail to indicate that it's turned off as shown here. To make the layer mask visible again, just click on it.
How can I see just the layer mask itself, in black and white like an Alpha channel, so I can see if I missed any areas I'm trying to fill in? Just Option-click PC: Alt-click directly on the layer mask thumbnail in the Layers palette. To return to the regular view, just Option-click again. Control-J to duplicate the Background layer. If the image is too light, simply change the layer blend mode to Multiply, which makes the image quite a bit darker.
Often, this will do the trick, but if it's too dark, all you have to do is lower the opacity for this Multiply layer until the image looks good to you. You're basically "dialing in" your ideal black-and-white image. Although this works a surprising amount of the time, there are also times where adding the Multiply layer makes parts of the image look great, while making other parts of the image look too dark.
If that's the case with your image, go on to the next step. Now, since the mask you just added is white it's white by default , your image doesn't changeit looks exactly the same.
However, you need to hide those areas that are too dark, and keep the darker areas that look good in other words, you need the best of all the layers. Then grab the Brush tool B , choose a medium-sized, soft-edged brush from the Brush Picker, and paint over the areas of the photo that are too dark as shown here, where we're painting over the rocks, because they look too dark. As you paint, those darker areas are hidden, and now those areas appear just like they did before you added the Multiply layer.
That's ityou've got one image that combines the best of the Lightness channel, and the best of the Multiply layer. Now you can flatten the image by choosing Flatten Image from the Layers palette's flyout menu to complete your black-and-white conversion. Previous page. Table of content. Next page. Scott Kelby. Lotus Notes and Domino 6 Development 2nd Edition.