Difference, Exclusion, Subtract, and Divide

Video: Difference, Exclusion, Subtract, and Divide

In this exercise, I am going to demonstrate the two Inversion modes; Difference and Exclusion. I'll also show you the two new modes inside of Photoshop, Subtract and Divide, which I am calling for lack of a better term, the Cancellation modes. We will also see how they're not necessarily all that new. They are, in fact, variations on blend modes that we already had. So, I'm working inside Bright shining light.psd and I want you to get a careful look at this image here, just remember it, because we'll be coming back to it in an unexpected way in just a few moments.

Difference, Exclusion, Subtract, and Divide

In this exercise, I am going to demonstrate the two Inversion modes; Difference and Exclusion. I'll also show you the two new modes inside of Photoshop, Subtract and Divide, which I am calling for lack of a better term, the Cancellation modes. We will also see how they're not necessarily all that new. They are, in fact, variations on blend modes that we already had. So, I'm working inside Bright shining light.psd and I want you to get a careful look at this image here, just remember it, because we'll be coming back to it in an unexpected way in just a few moments.

But I have the wrestlers layer active and it's set to the Linear Burn mode. I am going to go ahead and change that mode to Difference. Difference produces as kind of psychedelic effect, it's actually extremely useful and I'm going to be showing you a practical application of it. But first, I want you to understand how it works. It's like the Subtract mode, in that it subtracts a pixel in the Active layer from an equivalent pixel in the composite view below. So that equation is basically B-A, just as it is with the Subtract mode. The difference is that you're taking the absolute value that is the subtraction never produces a negative number.

If it does, it just passed back up and becomes positive again. So difference will start by reducing the luminance of the image and then it will pop back up and increase the luminance once again. So you get these trippy inversion effects. The great thing is that it's a selective inversion. So Black doesn't invert at all which is why the black of the clothing is not performing an inversion. If I turn off the wrestlers layer, this is what the background parchment looks like. So it's bright, it's orange. When we turn on wrestlers, it remains bright and orange inside of their clothing and then it inverts in the white background.

So white inverts absolutely; all the other luminance levels invert based on their brightness on a channel-by-channel basis. So if you want to produce more normalized effect, you'd go ahead and invert the layer itself and you can do that if you're working along with me just by turning on this Invert Adjustment layer. Because it's clipped to the wrestlers layer, the default behavior inside of Photoshop is that the inversion happens first and then the blend mode is assigned. So when I turn this layer on, we can't see the effect applied to the thumbnail. But what we now have is white clothing and a black background, so the background is no longer inverting the parchment below it, but the clothing is, because it actually appears white to the blend mode.

All right, so as I say very useful mode for figuring out the differences between images, I will show you what that means coming right up. Now one more thing you should know is that similar colors cancel each other out. So if the Difference mode finds a blue pixel on the active layer and a blue pixel on the layers below, then it goes ahead and produces black. If you would rather produce gray instead, then you can switch to the next mode. That's the only real difference between these two, is exclusion is going to produce gray instead of black where similar colors are encountered. Otherwise, pretty much everything I told you applies; the luminance levels are inverting each other on a channel-by-channel basis.

If you want to see what this looks like without the invert layer then just go ahead and turn it off and we end up getting this effect here, and again, this is the Difference mode right there. A darker mode has punchier shadows and this is the exclusion mode which has a lighter touch to it. All right, here is the Subtract mode right there and Subtract goes ahead and does the same thing as Difference, except without the absolute value. So black isn't going to do anything because subtracting 0 results in the same color you have before. White is going to do a real number on the luminance because when you subtract white, since it's the biggest color there, you are going to wipe out any of your other luminance levels and that's certainly what's happening in the background here.

So just by way of a comparison, if I press Shift+Alt+E or Shift+Option+E on the Mac, that takes us to the Difference mode and what we're really seeing a difference between Difference and Subtract is in that dark background that brightens up considerably. All right, I am going to press Ctrl+Z or Command+Z on the Mac to return to the Subtract mode because it does not have a keyboard shortcut. I am going to turn on this invert layer so we can see what happens, when we subtract an inverted version of the image and we end up getting this amazingly familiar effect right here. In fact, now, I just want you to notice, this wrestlers is set to Subtract, so we can see this Subtract mode and the invert layer is turned on.

I am going to go up to the File menu and choose the Revert command to revert back to the Linear Burn version of the image and it's exactly the same. We did not see a single pixel change there inside the image window and yet, the wrestlers layer is now set to Linear Burn and the invert layer is turned off. Well, to confirm that's what really happened that we aren't seeing any difference, let's check out the math because whatever you think of the math, it never lies. I am going to go ahead and twirl up the text elements layer and turn on the blend math layer, scroll down a little bit, and notice, Linear Burn right there, is A+B-1.

That doesn't sound much like B-A, which is this subtract equation, but watch this. I'll go ahead and get my Type tool and edit this layer for you. I am going to enter an equal sign because ultimately, the two will be equal, and I am going to say B-A because that's the equation for subtract. But when you invert the A layer, it turns into this, in parentheses 1-A and end parentheses like that ((1-A)). So it's B minus the product 1 minus A (B-(1-A)) and if you go ahead and spin that math out, why then you get minus minus for A, those two cancel each other out so you get a positive A. The B was already positive so it's A+B and then minus is assigned to the 1 gives us a -1.

So they are in fact exactly the same operations. Subtracting an inverted layer produces the exact same effect as not inverting the layer and assigning the Linear Burn mode. We also have something that's resembling a Divide mode right over here in the case of Color Dodge. Notice we have B/(1-A). Well, the equation for the Divide mode which we we're about to see is just B/A. So, if we invert that A, we are going to get the same effect as Color Dodge.

Let's go ahead and prove that to be true here. I am going to twirl close the text elements group just so that I can get to some of my other layers here. Now I'll go ahead and set up the scene a little bit. I'll twirl open future stuff and I'll turn on bright to dark, so that we're darkening up the background layer and then I'll twirl that closed once again. Let's select the wrestlers layer and I am going to go ahead and change that blend mode to Color Dodge right there because this is the one that's B/(1-A), and we get this effect and I like it better if it's inverted. So we'll go ahead and turn on Inversion for this effect, like so, and I will save off this effect as a layer Comp.

I will go ahead and click on the Page icon and I'll call this Inverted Color Dodge like so, just so we can keep track of it. Actually Inverted, pardon me; I'll go ahead and enter an ed. Make sure Appearance is turned on that's important. So we save those Blend modes. Click OK. All right, now I am going to change the Blend mode for wrestlers from Color Dodge all the way down here to Divide. Then I am going to turn the Inversion off and we have that exact same effect. Just to confirm that it is exactly the effect we had ten seconds ago, I will click in front of Inverted Color Dodge and notice nothing changed onscreen whatsoever.

So I was working free and easily with the inversion; I ended up inverting both the layers as I was applying the operation, but that's a pretty easy thing to do that's something you can do to change the balance of power where these various blended layers are concerned. All right, so that gives you a sense of what to expect from these Blend modes. In the next exercise, I am going to show you a very practical application of Difference.

Show transcript

This video is part of

Photoshop CS5 One-on-One: Mastery

192 video lessons · 43691 viewers

Author

Expand all | Collapse all
1. Introduction

40m 45s
1. Welcome
2m 45s
2. Making Photoshop your default image editor
7m 43s
3. Installing the dekeKeys keyboard shortcuts
8m 10s
4. Remapping OS shortcuts
7m 37s
5. Installing the Best Workflow color settings
4m 31s
6. The color settings explained
6m 54s
3m 5s
2. 25. What Photoshop Can Do, Pt. 3: The Face Paint

1h 11m
1. Your creative range continues to expand
1m 46s
2. The Avatar project so far
2m 38s
3. Painting on a photograph
7m 50s
6m 14s
5. Simulating chalky white paint
7m 23s
6. Masking and placing an image
7m 20s
7. Upsampling and Lens Blur
5m 9s
8. Blending blurry elements
3m 48s
9. Making a Smart Object
6m 46s
10. Placing an image as a Smart Object
3m 22s
11. Blending away a background
5m 56s
12. Applying Smart Filters
4m 34s
13. Creating a glow with Lens Flare
3m 45s
14. Blending and masking a glow
5m 3s

1h 26m
1. Using the image to select itself
1m 53s
6m 32s
3. Making an alpha channel
6m 54s
4. Using the Calculations command
6m 48s
5. Add, Subtract, Offset, and Scale
5m 54s
6. Prepping an image with the Dodge tool
6m 55s
7. Fixing mistakes before they get too big
6m 32s
8. Painting in the Overlay mode
5m 51s
9. Exaggerating and selecting flesh tones
7m 39s
10. Smudge, Median, and the Blur tool
6m 59s
6m 7s
5m 45s
13. Masking and compositing the foreground
5m 27s
14. Finessing the final composition
7m 39s
4. 27. Everything About the Pen Tool

2h 24m
1. Connecting the dots
1m 40s
2. The Pen tool and the Paths panel
6m 32s
3. Drawing a straight-sided outline
6m 25s
4. Editing a path outline
6m 36s
5. Adding and editing smooth points
5m 35s
6. Creating vector masks with the shape tools
4m 59s
7. Building a complex outline from shapes
4m 26s
8. Subtracting and transforming shapes
6m 45s
9. Cloning, flipping, and combining shapes
8m 58s
10. Roughing in non-symmetrical paths
7m 41s
11. Finessing a complex outline
9m 15s
8m 26s
13. Isolating an image element
6m 8s
14. Smooth points and control handles
9m 3s
15. Stretching curved segments
7m 49s
16. Using the Rubber Band option
9m 33s
17. Drawing smooth points with the Pen tool
6m 59s
3m 45s
19. Drawing cusp points
7m 14s
20. Setting points in the pasteboard
9m 57s
21. Using the Convert Point tool
6m 42s
5. 28. Blend Modes Revealed

2h 57m
1. Everything you need to know about blending
1m 45s
2. Photoshop CS5's blend modes
7m 21s
3. Cycling between blend modes
6m 15s
4. Darken and Lighten and their derivatives
6m 3s
5. The blend mode shortcuts
8m 6s
6. The Multiply and Burn modes
4m 28s
7. The Screen and Dodge modes
6m 0s
8. How opposite blend modes work
8m 24s
9. Why Multiply darkens and Divide lightens
5m 23s
10. Cleaning up a client's bad art
5m 3s
11. Dropping out a white background
5m 56s
12. Blending inside blend modes
8m 3s
13. Overlay, Soft Light, and Hard Light
6m 26s
14. Vivid, Linear, and Pin Light (and Hard Mix)
6m 35s
15. Difference, Exclusion, Subtract, and Divide
7m 34s
16. Great uses for the Difference mode
6m 18s
17. Promising uses for the Divide mode
9m 6s
18. Hue, Saturation, Color, and Luminosity
7m 0s
19. Blending an inverted layer
3m 32s
20. The "Fill Opacity Eight"
7m 25s
21. Making bad blend modes good
5m 16s
22. Making a knockout layer
6m 53s
23. Blending in the CMYK mode
8m 3s
24. Overprinting black text
8m 29s
25. Using the Luminance slider
5m 24s
6m 21s
27. Adjusting the behavior of luminance effects
10m 8s
6. 29. The Power of Smart Objects

2h 2m
1. Smart Objects = protective containers
1m 35s
2. Placing an Illustrator graphic
6m 30s
3. Vector copy and paste options
6m 56s
4. Applying Puppet Warp to vectors
8m 9s
5. "Gluing" vector art for Puppet Warp
5m 50s
6. Warping art onto the surface of an image
8m 7s
7. Blending a Smart Object
4m 30s
8. Blurring and blending a Smart Object
6m 8s
9. Making changes in Illustrator
5m 57s
10. Creating "true clones"
7m 18s
11. Double-flipping text
4m 44s
12. Applying effects to multiple layers
3m 24s
13. Updating true clones in one operation
7m 36s
14. Editing JPEGs as Camera Raw objects
5m 49s
15. Creating a double-exposure effect
7m 15s
7m 47s
17. Applying and repeating Camera Raw edits
6m 9s
18. Copying vs. cloning a Smart Object
5m 18s
19. Flipping a Smart Object and its mask
3m 42s
20. Adjusting multiple Camera Raw clones
3m 53s
21. Text that inverts everything behind it
5m 34s
7. 30. Nondestructive Smart Filters

1h 59m
1. This time, "smart" means dynamic
1m 37s
2. Introducing Smart Filters
6m 28s
5m 17s
4. Smart High Pass in the Lab mode
7m 57s
5. Sharpening a high-frequency image
7m 46s
6. Retroactively reducing noise
7m 31s
7. Which filters are Smart Filters?
6m 20s
8. Shadows/Highlights as a Smart Filter
4m 37s
9. Nesting one Smart Object inside another
7m 11s
10. Drawing a mask from a nested Smart Object
8m 7s
9m 16s
12. Tempering saturation values in Lab
7m 0s
13. Filtering live, editable text
9m 2s
14. Enhancing filters with layer effects
4m 33s
15. Applying a filter multiple times
5m 0s
16. Creating a synthetic star field
7m 7s
17. Making a stucco or drywall pattern
6m 28s
18. Land, sea, and clouds
8m 30s
8. 31. The Bristle and Mixer Brushes

2h 50m
2m 3s
2. Canvas texture and brush libraries
6m 40s
3. Painting with a predefined custom brush
9m 21s
4. Dissecting a custom brush
11m 9s
5. Designing and using a custom brush
4m 54s
5m 27s
7. The ten styles of bristle brushes
9m 47s
8. Size, Spacing, and Angle
7m 2s
9. Using the Bristle Brush preview
7m 53s
10. Bristles, Length, Thickness, and Stiffness
6m 53s
11. Stylus tilt and mouse behavior
5m 25s
12. Stroking a path outline with a brush
4m 0s
13. Troubleshooting a stylus
5m 49s
14. Introducing the Mixer Brush
7m 22s
15. The Load, Mix, and Wet values
5m 1s
6m 26s
17. Shading a piece of graphic art
6m 34s
7m 53s
19. Mixing a photographic portrait
6m 11s
20. Tracing the fine details in an image
5m 52s
21. Crosshatching and brush size
5m 53s
22. Covering up and augmenting details
7m 36s
23. Painting in hair and fabric
5m 54s
24. Painting and scaling very fine hairs
8m 7s
25. Adding texture with the Emboss filter
8m 31s
26. Exploiting a "happy accident"
2m 46s
9. 32. Auto-Align, Auto-Blend, and Photomerge

1h 40m
1. Artificial intelligence that works
1m 22s
2. The Auto-Align Layers command
7m 25s
3. The Auto-Blend Layers command
3m 54s
4m 50s
5. The Geometric Distortion setting
6m 44s
6. The Seamless Tones and Colors checkbox
4m 8s
7. Creating the best possible layer mask
9m 18s
8. Auto-blending depths of field
5m 54s
6m 29s
10. Shooting and downsampling panorama images
5m 54s
11. Introducing the Photomerge command
6m 40s
12. Evaluating the Layout settings
6m 47s
5m 36s
14. Tracing and extracting seams
7m 18s
5m 55s
16. Simplifying and correcting a panorama
5m 58s
17. Smart Filters and nondestructive cropping
6m 43s
10. 33. High Dynamic Range (HDR Pro)

1h 18m
1. The most mysterious of mysterious topics
2m 29s
2. Introducing HDR Toning
6m 43s
3. Reigning in clipped highlights
5m 54s
9m 5s
5. Nondestructive editing with HDR Toning
8m 22s
6. Using the HDR Toning Curve
7m 2s
6m 0s
8. Merging multiple exposures
7m 14s
9. A first look at HDR Pro
6m 24s
10. Removing ghosts, correcting backlighting
7m 11s
11. Generating and editing an HDR comp
7m 0s
12. HDR rendered to completion
5m 19s
11. 34. Actions and Batch Processing

1h 27m
1. Processing hundreds of files in no time
1m 43s
2. Creating an action set
6m 37s
3. Making an action
7m 7s
4. Stop, Delete, and Record
7m 12s
6m 40s
6. Playing and testing an action
6m 31s
7. Playing and editing a specific operation
6m 39s
8. Permitting the user to change settings
4m 58s
9. Explaining an action with a custom stop
5m 0s
10. Batch-processing multiple images
7m 22s
11. Adding a Save As operation
6m 34s
12. Creating an action to save web graphics
7m 59s
13. Batching two actions into one
7m 15s
5m 30s

1m 19s
1. See ya
1m 19s

Start learning today

Sometimes @lynda teaches me how to use a program and sometimes Lynda.com changes my life forever. @JosefShutter
@lynda lynda.com is an absolute life saver when it comes to learning todays software. Definitely recommend it! #higherlearning @Michael_Caraway
@lynda The best thing online! Your database of courses is great! To the mark and very helpful. Thanks! @ru22more
Got to create something yesterday I never thought I could do. #thanks @lynda @Ngventurella
I really do love @lynda as a learning platform. Never stop learning and developing, it’s probably our greatest gift as a species! @soundslikedavid
@lynda just subscribed to lynda.com all I can say its brilliant join now trust me @ButchSamurai
@lynda is an awesome resource. The membership is priceless if you take advantage of it. @diabetic_techie
One of the best decision I made this year. Buy a 1yr subscription to @lynda @cybercaptive
guys lynda.com (@lynda) is the best. So far I’ve learned Java, principles of OO programming, and now learning about MS project @lucasmitchell
Signed back up to @lynda dot com. I’ve missed it!! Proper geeking out right now! #timetolearn #geek @JayGodbold
Share a link to this course

What are exercise files?

Exercise files are the same files the author uses in the course. Save time by downloading the author's files instead of setting up your own files, and learn by following along with the instructor.

Can I take this course without the exercise files?

Yes! If you decide you would like the exercise files later, you can upgrade to a premium account any time.

How to use exercise files.

Learn by watching, listening, and doing, Exercise files are the same files the author uses in the course, so you can download them and follow along Premium memberships include access to all exercise files in the library.

Exercise files

How to use exercise files.

This course includes free exercise files, so you can practice while you watch the course. To access all the exercise files in our library, become a Premium Member.

Are you sure you want to mark all the videos in this course as unwatched?

This will not affect your course history, your reports, or your certificates of completion for this course.

Congratulations

You have completed Photoshop CS5 One-on-One: Mastery.

Become a member to add this course to a playlist

Join today and get unlimited access to the entire library of video courses—and create as many playlists as you like.

Become a member to like this course.

Join today and get unlimited access to the entire library of video courses.

Exercise files

Learn by watching, listening, and doing! Exercise files are the same files the author uses in the course, so you can download them and follow along. Exercise files are available with all Premium memberships. Learn more

How to use exercise files.

Thanks for contacting us.
You’ll hear from our Customer Service team within 24 hours.

Please enter the text shown below:

The classic layout automatically defaults to the latest Flash Player.

To choose a different player, hold the cursor over your name at the top right of any lynda.com page and choose Site preferencesfrom the dropdown menu.

• Mark video as unwatched
• Mark ALL videos as unwatched
Exercise files

Access exercise files from a button right under the course name.

Mark videos as unwatched

Remove icons showing you already watched videos if you want to start over.

Make the video wide, narrow, full-screen, or pop the player out of the page into its own window.

Interactive transcripts

Click on text in the transcript to jump to that spot in the video. As the video plays, the relevant spot in the transcript will be highlighted.

Are you sure you want to delete this note?

Thanks for signing up.

We’ll send you a confirmation email shortly.

• new course releases
• general communications
• special notices

Keep up with news, tips, and latest courses with emails from lynda.com.

• new course releases