Photoshop CS4 One-on-One: Mastery

Employing a Difference mask


Photoshop CS4 One-on-One: Mastery

with Deke McClelland

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Video: Employing a Difference mask

I have saved my progress so far as One difference.psd because so far I have set one of the layers to the Difference mode and this dude right here in the middle is blending with his very own bottom down here at the bottom of the stack. What do we do with that? Well, we would come back to it in just a second. Now I want you to go to Stunt cyclist-2.jpg, turn it on and set it to the Difference mode and that's Shift+Alt+E by the way or Shift+Option+ E on the Mac. You have got Difference, on top of Difference, on top of Difference, which is pretty close to what we want, but we also have all this garbage down here.
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  1. 21m 20s
    1. Welcome
      1m 21s
    2. Installing the DekeKeys keyboard shortcuts
      5m 38s
    3. Resetting the Function keys on a Mac
      3m 51s
    4. Installing the CS4 color settings
      4m 37s
    5. Setting up the CS4 color settings
      5m 53s
  2. 2h 31m
    1. Introduction to masking
    2. Introducing color range
      4m 22s
    3. Adding base colors and adjusting fuzziness
      4m 46s
    4. Localized color clusters
      6m 12s
    5. The Quick Mask mode
      7m 33s
    6. Viewing a quick mask by itself
      6m 40s
    7. Testing the quality of edges
      3m 55s
    8. Introducing the Masks palette
      7m 45s
    9. Editing a layer mask
      6m 18s
    10. Choking a mask with Gaussian Blur and Levels
      6m 44s
    11. Choking a mask with Mask Edge
      7m 43s
    12. Adding a Gradient Overlay shadow
      4m 23s
    13. Using live Density and Feather
      6m 12s
    14. Journeyman masking
      5m 44s
    15. Creating an alpha channel
      7m 6s
    16. Increasing contrast
      7m 15s
    17. Overlay painting
      8m 28s
    18. Cleaning up whites and blacks
      5m 48s
    19. Soft light painting
      5m 47s
    20. Selecting in style
      6m 55s
    21. Employing masks as selections
      5m 2s
    22. Scaling and compositing layers
      6m 30s
    23. Compositing glass
      5m 10s
    24. Selecting glass highlights
      8m 41s
    25. Working with found masks
      5m 46s
  3. 1h 34m
    1. Introduction to vector-based shapes
      1m 10s
    2. Vector-based type outlines
      7m 23s
    3. The benefits of vectors
      6m 27s
    4. Upsampling vs. nondestructive scaling
      7m 35s
    5. Vectors and effects
      8m 7s
    6. Fill Opacity and clipped layers
      4m 24s
    7. Basic shape creation
      3m 15s
    8. Drawing interacting shapes
      6m 21s
    9. Power-duplicating paths
      3m 12s
    10. Combining pixels and vector masks
      5m 19s
    11. Line tool and layer attributes
      7m 5s
    12. Copying and pasting path outlines
      3m 28s
    13. Drawing custom shapes
      3m 59s
    14. Drawing with the Pen tool
      7m 48s
    15. Creating cusp points
      7m 28s
    16. Defining a custom shape
      3m 34s
    17. Assigning a vector mask to an image
      2m 38s
    18. Adding a vector object to a composition
      5m 40s
  4. 1h 24m
    1. Introduction to Vanishing Point
      1m 11s
    2. Creating and saving the first plane
      8m 9s
    3. Creating perpendicular planes
      5m 16s
    4. Healing in perspective
      8m 47s
    5. Cloning and scaling in perspective
      8m 34s
    6. Patching an irregularly shaped area
      6m 59s
    7. Healing between planes
      3m 35s
    8. Importing an image into a 3D scene
      5m 46s
    9. Adding perspective type
      5m 37s
    10. Removing and matching perspective
      5m 36s
    11. Applying a reflection in perspective
      5m 1s
    12. Creating a perspective gradient
      6m 11s
    13. Converting a gradient to a mask
      2m 58s
    14. Swinging planes to custom angles
      4m 32s
    15. Wrapping art around multiple surfaces
      5m 49s
  5. 1h 15m
    1. Introduction to Smart Objects
    2. Placing a Smart Object
      5m 7s
    3. Saving a PDF-compatible AI file
      4m 27s
    4. Performing nondestructive transformations
      6m 8s
    5. Editing a Smart Object in Illustrator
      6m 50s
    6. Converting an image to a Smart Object
      6m 50s
    7. Cloning Smart Objects
      5m 24s
    8. Creating a multilayer Smart Object
      5m 51s
    9. Updating multiple instances at once
      2m 55s
    10. Creating a Camera Raw Smart Object
      4m 17s
    11. Editing a Camera Raw Smart Object
      3m 25s
    12. Assembling a layered ACR composition
      5m 55s
    13. Using an ACR Smart Object to effect
      3m 41s
    14. Blending multiple ACR portraits
      6m 56s
    15. Live type that inverts everything behind it
      6m 33s
  6. 1h 48m
    1. Introducing nondestructive Smart Filters
    2. Applying a Smart Filter
      4m 22s
    3. Adjusting filter and blend settings
      4m 25s
    4. Heaping on the Smart Filters
      5m 19s
    5. Smart Filter stacking order
      7m 23s
    6. Resolution and Smart Filter radius
      6m 12s
    7. Masking Smart Filters
      4m 42s
    8. Employing nested Smart Objects
      5m 5s
    9. Dragging and dropping Smart Filters
      6m 31s
    10. Using the Shadows/Highlights filter
      5m 53s
    11. Regaining access to the pixels
      7m 8s
    12. Parametric wonderland
      5m 52s
    13. Working with the Filter Gallery
      6m 28s
    14. Freeform filter jam
      5m 52s
    15. Swapping filters from the Filter Gallery
      3m 45s
    16. Mixing all varieties of parametric effects
      7m 30s
    17. Addressing a few Smart Filter bugs
      3m 11s
    18. Applying a Smart Filter to live type
      5m 30s
    19. Choking letters with Maximum
      3m 7s
    20. Duplicating a Smart Filter
      2m 38s
    21. Enhancing a filter with a layer effect
      6m 30s
  7. 1h 6m
    1. Introduction to Auto-Align, Auto-Blend, and Photomerge
      1m 2s
    2. Merging two shots into one
      3m 49s
    3. Applying Auto-Align layers
      3m 44s
    4. Masking images into a common scene
      1m 39s
    5. Auto-Align plus Auto-Blend
      8m 11s
    6. Assigning weighted Opacity values
      4m 7s
    7. Employing a Difference mask
      7m 17s
    8. Masking smarter, not harder
      3m 53s
    9. Capturing multiple depths of field
      3m 37s
    10. Auto-blending real focus
      8m 31s
    11. Creating a panorama with Photomerge
      7m 27s
    12. Correcting a seamless panorama
      4m 52s
    13. An altogether nondestructive Lab correction
      7m 59s
  8. 1h 44m
    1. Introduction to new CS4 technologies
      1m 1s
    2. Applying Content-Aware Scale
      7m 18s
    3. What works and what doesn't with Content-Aware Scale
      4m 19s
    4. Protecting areas with masks
      7m 31s
    5. Applying incremental edits
      7m 6s
    6. Protecting skin tones
      7m 12s
    7. Scaling around a model with TLC
      9m 0s
    8. Adjusting the scale threshold
      5m 22s
    9. When Content-Aware Scale fails
      4m 2s
    10. Creating a lens distortion effect
      8m 39s
    11. Layer masking the family
      11m 44s
    12. Installing the Pixel Bender
      3m 43s
    13. Introducing Pixel Bender kernels
      6m 50s
    14. Pixel Bender kernel roundup
      7m 24s
    15. Tube View and Ripple Blocks
      3m 58s
    16. Making a seamless pattern with Kaleidoscope
      6m 13s
    17. Introducing the Pixel Bender Toolkit
      3m 24s
  9. 1h 20m
    1. Introduction to actions
    2. Creating an action
      5m 45s
    3. Recording operations
      5m 12s
    4. Reviewing and editing an action
      4m 45s
    5. Playing an action (the Button Mode)
      4m 51s
    6. Saving and loading actions
      5m 0s
    7. Copying and modifying an action
      4m 8s
    8. Permitting the user to change settings
      5m 50s
    9. The Best Chrome Effect Ever II
      3m 41s
    10. Recording a fail-safe action
      7m 33s
    11. Rounding corners with a mask
      4m 33s
    12. Cleaning up layers
      3m 52s
    13. Automating layer effects
      7m 1s
    14. Applying chrome with Gradient Map
      6m 24s
    15. Action anomalies
      4m 11s
    16. Rendering effects to layers
      5m 1s
    17. Testing that it works
      2m 0s
  10. 1m 14s
    1. See ya
      1m 14s

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Watch the Online Video Course Photoshop CS4 One-on-One: Mastery
13h 7m Advanced May 29, 2009

Viewers: in countries Watching now:

Photoshop mastery can be elusive, but in Photoshop CS4 One-on-One: Mastery, best-selling author and video trainer Deke McClelland teaches the most powerful, unconventional, and flexible features of the program. In this third and final installment of the popular and comprehensive series, Deke delves into the strongest features that Photoshop has to offer, including scalable vector graphics, Smart Objects, and Photomerge. Exercise files accompany the course.

Recommended prerequisites: Photoshop CS4 One-on-One: Fundamentals and Photoshop CS4 One-on-One: Advanced, both part of the Online Training Library®.

Download Deke's customized keyboard layouts and color settings for Photoshop from the Exercise Files tab.

Topics include:
  • Defining the essentials of masking
  • Resizing images with content-aware scaling
  • Adjusting perspective with Vanishing Point
  • Applying Smart Filters to create complex effects
  • Using the Auto-Align tool to build composite images
Design Photography
Deke McClelland

Employing a Difference mask

I have saved my progress so far as One difference.psd because so far I have set one of the layers to the Difference mode and this dude right here in the middle is blending with his very own bottom down here at the bottom of the stack. What do we do with that? Well, we would come back to it in just a second. Now I want you to go to Stunt cyclist-2.jpg, turn it on and set it to the Difference mode and that's Shift+Alt+E by the way or Shift+Option+ E on the Mac. You have got Difference, on top of Difference, on top of Difference, which is pretty close to what we want, but we also have all this garbage down here.

So it's not really going to be the thing we are looking for. And then if we do another Difference by going up here to the Stunt cyclist-1 and turning it on and then setting it to the Difference mode by pressing Shift+Alt+E or Shift+Option+E on the Mac, then we have another one of these just completely weird combinations of images. And you know what? I'm going to tell you something. I'm not going to use Stunt cyclist -1 anyway. So we might as well turn him off. He is just too near to the Stunt cyclist-2 right there. So what's the point? These three guys tell the story. But as I say, even though they are looking closer to the final scene that I want, not only do we have this weird stuff going on underneath but the first cyclist is looking good. This guy that's associated with Stunt cyclist-2.jpg, that layer. But the next guy has got some psychedelic groovy coloring going on and so does his friend with the bottom.

So what do we do about all that? Well, we use this information in order to create a mask. So I'm going to turn off Stunt cyclist-2 for a moment and this is going to be great for masking the rear end of this dude, not the front where we have the bottom problem but the rear end of this middle guy. Let's go to the Channel palette for just a moment and let's go to the Blue channel because that's where we have the most difference. I mean you can check him out. Here is Red and here is Green and here is Blue and Blue has the highest degree of contrast. That's what I mean by that.

So let's go ahead and select this region right here like so, just a general selection with the Marquee tool that gets very close to but does not touch this other fellow's rear end. All right now, what I want you to do is just create a new alpha channel by clicking on the page icon, not the Save selection as channel icon, because that just saved the rectangle. But rather you want the New Channel icon. So go ahead and Alt-click or Option-click on it and we'll call this center because he is right there in the center of the image and I'll click OK.

And then oops! Forgot something. Let's go back to Blue and I want to copy this information there. So I'll go to the Edit menu and I'll choose Copy Merged or press Ctrl+Shift+C. That's what you got to do because it's merging your multiple layers. Command+Shift+C on the Mac and I know, I told you there are no layers in channels. Channels are always flat. That's still true, but that's command you have got to select. Now go to center like so and press Ctrl+V or Command+V on a Mac in order to select that area. All right, so far so good. Let's go back to the RGB composite image and go back to Layers palette, turn off this bottom dude right there, Stunt cyclist-4 and because Stunt cyclist-3 has nothing to interact with, it looks normal now.

Now turn on Stunt cyclist-2 like so and guess what? He is good for the forward part of the image. Is he not? Because the bottom guy is missing. So now let's go to the Channels palette. Let's go actually to the Blue once again, very important. Press Ctrl+Shift+C, Command +Shift+C on a Mac in order to copy a merged version of the information. Go to center and press Ctrl+V or Command+V on the Mac to paste in the front of the bicycle and if you click off, there is virtually no seam at the intersection of those two Rectangular Marquees.

Looks pretty darn good and what the heck? Let's just go ahead and press Ctrl+L, Command+L on the Mac in order to bring up the Levels dialog box and we'll increase the heck out of the Contrast here by lightening the highlights. Now it looks like he is jumping in front of the surface of the moon, which is totally awesome. So let's take some of that lunar landscape away by moving up the black point value and if you think you are getting too jagged results, as you might, let's ease off the white point value, take it up to 50.

Now notice that we are not selecting everything exactly right and that's okay as you will see. It works up pretty nicely. Go ahead and click OK at this point. And then we have a nice center mask. Ctrl-click on it or Command-click on that center mask in order to load it as the selection outline. Go back to the RGB composite, go to the Layers palette and this is the mask for Stunt cyclist-3. So go ahead and click on it to make it active. Turn off Stunt cyclist-2 right there and let's go ahead and assign the mask and we are going to actually restore the blend mode of Normal and I'll turn on Stunt cyclist-4, so that we can see him up here on the background.

And now I'll click on my little Mask icon. Again, for Stunt cyclist-3, very important. That's the layer that we are working on. And I'll click on the tiny layer mask icon and there we have it. We have now masked him into place. Now we could have done it the other way around where the bottom is covering up the wheel. I just didn't like the way that looked. This one implies the motion of the scene much better. All right, so now at this point you are looking at it going "well he is missing some of his face, Deke and we can see blue through this shoes and this shoe is kind of missing and we have got some problems inside the wheel." No we don't. Watch this.

We will go ahead and switch over to the Brush tool and then make sure the Foreground color is set to white. If not switch it around. I'm sick of this Normal mode being active. So I'm going to press the Escape key so that goes away and then I can make my brush bigger by pressing the Right Bracket key and I also have a very fuzzy brush and watch this. I'll just paint him into place. Isn't that awesome? I'm just sang it because it's so simple and watch it though. Don't get too near to the bottom or you are going to make it fade out a little bit like I did. So why don't we go ahead and undo that. Because I can't just now paint in black, because I paint that wheel away so undo that modification. I got too into my little tune. So I'm going to paint this away once again, but because we have auto-aligned everything, we should have no problems with revealing weird details. You just don't want to paint too high, so that you paint in the edge.

Or maybe your do, you can just crop that away later. But if you don't want to crop that area away, then you would the X key to paint with black and go ahead and paint that edge away like so. And it looks awfully darn good. Now, the only thing to be done at this point is do the other guy, in other words, oops! That's wrong. Press the X key, paint closer along the wheel. I do want to get some of that wheel in there. This area here we are going to keep it the way it is. We are not going to try to do a better job in masking along the wheel that's next to his bottom, because it's really just not worth it. You can just really go crazy in that area if you want to, but I'm going to leave it the way it is because I think it looks great.

The other thing to do now is to go ahead and merge Stunt cyclist-2 in to the picture, because we need that 3rd cyclist in order to complete the composition. But you know what? We are out of time. So in the next exercise we are going to have a chance to do the exact same thing we just got done doing. I'm not sure I have anything new to impart. But it's always a great idea to try out those techniques again so that you remember them the next time around and this is a really swell technique. So stay tuned.

Find answers to the most frequently asked questions about Photoshop CS4 One-on-One: Mastery .

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Q: My Polygon tool is locked into a very small size. I can use the Transform tool to increase it's size once drawn, but I must have something set that will not allow me to freely draw it like I can the other shapes. What could be causing this problem?
A: This could be caused by a value associated with the Radius option of the tool. Click the down-pointing arrowhead to the right (a few tool icons over) from the Polygon tool in the options bar at the top of the screen. This brings up pop-up panel. If the Radius option has a number value, select that value and press Delete or Backspace to clear it out. That should fix the problem.
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