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  1. Photoshop User Guide
  2. Introduction to Photoshop
    1. Dream it. Make it.
    2. What's new in Photoshop
    3. Edit your first photo
    4. Create documents
    5. Photoshop | Common Questions
    6. Photoshop system requirements
    7. Get to know Photoshop
    8. Keep Photoshop up to date
  3. Photoshop and other Adobe products and services
    1. Work with Illustrator artwork in Photoshop
    2. Work with Photoshop files in InDesign
    3. Substance 3D Materials for Photoshop
    4. Use the Capture in-app extension in Photoshop
  4. Photoshop on the iPad (not available in mainland China)
    1. Photoshop on the iPad | Common questions
    2. Get to know the workspace
    3. System requirements | Photoshop on the iPad
    4. Create, open, and export documents
    5. Add photos
    6. Work with layers
    7. Draw and paint with brushes
    8. Make selections and add masks
    9. Retouch your composites
    10. Work with adjustment layers
    11. Adjust the tonality of your composite with Curves
    12. Apply transform operations
    13. Crop and rotate your composites
    14. Rotate, pan, zoom, and reset the canvas
    15. Work with Type layers
    16. Work with Photoshop and Lightroom
    17. Get missing fonts in Photoshop on the iPad
    18. Japanese Text in Photoshop on the iPad
    19. Manage app settings
    20. Touch shortcuts and gestures
    21. Keyboard shortcuts
    22. Edit your image size
    23. Livestream as you create in Photoshop on the iPad
    24. Correct imperfections with the Healing Brush
    25. Create brushes in Capture and use them in Photoshop on the iPad
    26. Work with Camera Raw files
    27. Create and work with Smart Objects
    28. Adjust exposure in your images with Dodge and Burn
    29. Auto adjustment commands in Photoshop on the iPad
    30. Smudge areas in your images with Photoshop on the iPad
    31. Saturate or desaturate your images using Sponge tool
    32. Content aware fill for iPad
  5. Photoshop on the web (not available in mainland China)
    1. Common questions
    2. System requirements
    3. Keyboard shortcuts
    4. Supported file types
    5. Introduction to the workspace
    6. Open and work with cloud documents
    7. Generative AI features
    8. Basic concepts of editing
    9. Quick Actions
    10. Work with layers
    11. Retouch images and remove imperfections
    12. Make quick selections
    13. Image improvements with Adjustment Layers
    14. Add a fill layer
    15. Move, transform, and crop images
    16. Draw and paint
    17. Draw and edit Shapes
    18. Work with Type layers
    19. Work with anyone on the web
    20. Manage app settings
    21. Generate Image
    22. Generate Background
    23. Reference Image
  6. Photoshop (beta) (not available in mainland China)
    1. Get started with Creative Cloud Beta apps
    2. Photoshop (beta) on the desktop
    3. Reference Image
  7. Generative AI (not available in mainland China) 
    1. Common questions on generative AI in Photoshop
    2. Generative Fill in Photoshop on the desktop
    3. Generate Image with descriptive text prompts
    4. Generative Expand in Photoshop on the desktop
    5. Replace background with Generate background
    6. Get new variations with Generate Similar
    7. Generative Fill in Photoshop on the iPad
    8. Generative Expand in Photoshop on the iPad
    9. Generative AI features in Photoshop on the web
  8. Content authenticity (not available in mainland China)
    1. Content credentials in Photoshop
    2. Identity and provenance for NFTs
    3. Connect accounts for creative attribution
  9. Cloud documents (not available in mainland China)
    1. Photoshop cloud documents | Common questions
    2. Photoshop cloud documents | Workflow questions
    3. Manage and work with cloud documents in Photoshop
    4. Upgrade cloud storage for Photoshop
    5. Unable to create or save a cloud document
    6. Solve Photoshop cloud document errors
    7. Collect cloud document sync logs
    8. Invite others to edit your cloud documents
    9. Share files and comment in-app
  10. Workspace
    1. Workspace basics
    2. Preferences
    3. Learn faster with the Photoshop Discover Panel
    4. Create documents
    5. Place files
    6. Default keyboard shortcuts
    7. Customize keyboard shortcuts
    8. Tool galleries
    9. Performance preferences
    10. Use tools
    11. Presets
    12. Grid and guides
    13. Touch gestures
    14. Use the Touch Bar with Photoshop
    15. Touch capabilities and customizable workspaces
    16. Technology previews
    17. Metadata and notes
    18. Place Photoshop images in other applications
    19. Rulers
    20. Show or hide non-printing Extras
    21. Specify columns for an image
    22. Undo and history
    23. Panels and menus
    24. Position elements with snapping
    25. Position with the Ruler tool
  11. Web, screen, and app design
    1. Photoshop for design
    2. Artboards
    3. Device Preview
    4. Copy CSS from layers
    5. Slice web pages
    6. HTML options for slices
    7. Modify slice layout
    8. Work with web graphics
    9. Create web photo galleries
  12. Image and color basics
    1. How to resize images
    2. Work with raster and vector images
    3. Image size and resolution
    4. Acquire images from cameras and scanners
    5. Create, open, and import images
    6. View images
    7. Invalid JPEG Marker error | Opening images
    8. Viewing multiple images
    9. Customize color pickers and swatches
    10. High dynamic range images
    11. Match colors in your image
    12. Convert between color modes
    13. Color modes
    14. Erase parts of an image
    15. Blending modes
    16. Choose colors
    17. Customize indexed color tables
    18. Image information
    19. Distort filters are unavailable
    20. About color
    21. Color and monochrome adjustments using channels
    22. Choose colors in the Color and Swatches panels
    23. Sample
    24. Color mode or Image mode
    25. Color cast
    26. Add a conditional mode change to an action
    27. Add swatches from HTML CSS and SVG
    28. Bit depth and preferences
  13. Layers
    1. Layer basics
    2. Nondestructive editing
    3. Create and manage layers and groups
    4. Select, group, and link layers
    5. Place images into frames
    6. Layer opacity and blending
    7. Mask layers
    8. Apply Smart Filters
    9. Layer comps
    10. Move, stack, and lock layers
    11. Mask layers with vector masks
    12. Manage layers and groups
    13. Layer effects and styles
    14. Edit layer masks
    15. Extract assets
    16. Reveal layers with clipping masks
    17. Generate image assets from layers
    18. Work with Smart Objects
    19. Blending modes
    20. Combine multiple images into a group portrait
    21. Combine images with Auto-Blend Layers
    22. Align and distribute layers
    23. Copy CSS from layers
    24. Load selections from a layer or layer mask's boundaries
    25. Knockout to reveal content from other layers
  14. Selections
    1. Get started with selections
    2. Make selections in your composite
    3. Select and Mask workspace
    4. Select with the marquee tools
    5. Select with the lasso tools
    6. Adjust pixel selections
    7. Move, copy, and delete selected pixels
    8. Create a temporary quick mask
    9. Select a color range in an image
    10. Convert between paths and selection borders
    11. Channel basics
    12. Save selections and alpha channel masks
    13. Select the image areas in focus
    14. Duplicate, split, and merge channels
    15. Channel calculations
  15. Image adjustments
    1. Replace object colors
    2. Perspective warp
    3. Reduce camera shake blurring
    4. Healing brush examples
    5. Export color lookup tables
    6. Adjust image sharpness and blur
    7. Understand color adjustments
    8. Apply a Brightness/Contrast adjustment
    9. Adjust shadow and highlight detail
    10. Levels adjustment
    11. Adjust hue and saturation
    12. Adjust vibrance
    13. Adjust color saturation in image areas
    14. Make quick tonal adjustments
    15. Apply special color effects to images
    16. Enhance your image with color balance adjustments
    17. High dynamic range images
    18. View histograms and pixel values
    19. Match colors in your image
    20. Crop and straighten photos
    21. Convert a color image to black and white
    22. Adjustment and fill layers
    23. Curves adjustment
    24. Blending modes
    25. Target images for press
    26. Adjust color and tone with Levels and Curves eyedroppers
    27. Adjust HDR exposure and toning
    28. Dodge or burn image areas
    29. Make selective color adjustments
  16. Adobe Camera Raw
    1. Camera Raw system requirements
    2. What's new in Camera Raw
    3. Introduction to Camera Raw
    4. Create panoramas
    5. Supported lenses
    6. Vignette, grain, and dehaze effects in Camera Raw
    7. Default keyboard shortcuts
    8. Automatic perspective correction in Camera Raw
    9. Radial Filter in Camera Raw
    10. Manage Camera Raw settings
    11. Open, process, and save images in Camera Raw
    12. Repair images with the Enhanced Spot Removal tool in Camera Raw
    13. Rotate, crop, and adjust images
    14. Adjust color rendering in Camera Raw
    15. Process versions in Camera Raw
    16. Make local adjustments in Camera Raw
  17. Image repair and restoration
    1. Remove Tool
    2. Remove objects from your photos with Content-Aware Fill
    3. Content-Aware Patch and Move
    4. Retouch and repair photos
    5. Correct image distortion and noise
    6. Basic troubleshooting steps to fix most issues
  18. Image enhancement and transformation
    1. Replace sky in your images
    2. Transform objects
    3. Adjust crop, rotation, and canvas size
    4. How to crop and straighten photos
    5. Create and edit panoramic images
    6. Warp images, shapes, and paths
    7. Vanishing Point
    8. Content-aware scaling
    9. Transform images, shapes, and paths
  19. Drawing and painting
    1. Paint symmetrical patterns
    2. Draw rectangles and modify stroke options
    3. About drawing
    4. Draw and edit shapes
    5. Painting tools
    6. Create and modify brushes
    7. Blending modes
    8. Add color to paths
    9. Edit paths
    10. Paint with the Mixer Brush
    11. Brush presets
    12. Gradients
    13. Gradient interpolation
    14. Fill and stroke selections, layers, and paths
    15. Draw with the Pen tools
    16. Create patterns
    17. Generate a pattern using the Pattern Maker
    18. Manage paths
    19. Manage pattern libraries and presets
    20. Draw or paint with a graphics tablet
    21. Create textured brushes
    22. Add dynamic elements to brushes
    23. Gradient
    24. Paint stylized strokes with the Art History Brush
    25. Paint with a pattern
    26. Sync presets on multiple devices
    27. Migrate presets, actions, and settings
  20. Text
    1. Add and edit the text
    2. Unified Text Engine
    3. Work with OpenType SVG fonts
    4. Format characters
    5. Format paragraphs
    6. How to create type effects
    7. Edit text
    8. Line and character spacing
    9. Arabic and Hebrew type
    10. Fonts
    11. Troubleshoot fonts
    12. Asian type
    13. Create type
  21. Filters and effects
    1. Use the Blur Gallery
    2. Filter basics
    3. Filter effects reference
    4. Add Lighting Effects
    5. Use the Adaptive Wide Angle filter
    6. Use the Oil Paint filter
    7. Use the Liquify filter
    8. Layer effects and styles
    9. Apply specific filters
    10. Smudge image areas
  22. Saving and exporting
    1. Save your files in Photoshop
    2. Export your files in Photoshop
    3. Supported file formats
    4. Save files in graphics formats
    5. Move designs between Photoshop and Illustrator
    6. Save and export video and animations
    7. Save PDF files
    8. Digimarc copyright protection
  23. Color Management
    1. Understanding color management
    2. Keeping colors consistent
    3. Color settings
    4. Duotones
    5. Work with color profiles
    6. Color-managing documents for online viewing
    7. Color-managing documents when printing
    8. Color-managing imported images
    9. Proofing colors
  24. Web, screen, and app design
    1. Photoshop for design
    2. Artboards
    3. Device Preview
    4. Copy CSS from layers
    5. Slice web pages
    6. HTML options for slices
    7. Modify slice layout
    8. Work with web graphics
    9. Create web photo galleries
  25. Video and animation
    1. Video editing in Photoshop
    2. Edit video and animation layers
    3. Video and animation overview
    4. Preview video and animations
    5. Paint frames in video layers
    6. Import video files and image sequences
    7. Create frame animations
    8. Creative Cloud 3D Animation (Preview)
    9. Create timeline animations
    10. Create images for video
  26. Printing
    1. Print 3D objects
    2. Print from Photoshop
    3. Print with color management
    4. Contact Sheets and PDF Presentations
    5. Print photos in a picture package layout
    6. Print spot colors
    7. Print images to a commercial printing press
    8. Improve color prints from Photoshop
    9. Troubleshoot printing problems | Photoshop
  27. Automation
    1. Creating actions
    2. Create data-driven graphics
    3. Scripting
    4. Process a batch of files
    5. Play and manage actions
    6. Add conditional actions
    7. About actions and the Actions panel
    8. Record tools in actions
    9. Add a conditional mode change to an action
    10. Photoshop UI toolkit for plug-ins and scripts
  28. Troubleshooting
    1. Fixed issues 
    2. Known issues
    3. Optimize Photoshop performance
    4. Basic troubleshooting
    5. Troubleshoot crash or freeze
    6. Troubleshoot program errors
    7. Troubleshoot scratch disk full errors
    8. Troubleshoot GPU and graphics driver issues
    9. Find missing tools
    10. Photoshop 3D | Common questions around discontinued features

Blend layers and channels

You can use the blending effects associated with layers to combine channels within and between images into new images. You can use either the Apply Image command (on single and composite channels) or the Calculations command (on single channels). These commands offer two additional blending modes not available in the Layers panel—Add and Subtract. Although it’s possible to create new combinations of channels by copying channels to layers in the Layers panel, you may find it quicker to use the calculation commands to blend channel information.

The calculation commands perform mathematical operations on the corresponding pixels of two channels (the pixels with identical locations in the image) and then combine the results in a single channel. Two concepts are fundamental to understanding how the calculation commands work:

  • Each pixel in a channel has a brightness value. The Calculations and Apply Image commands manipulate these values to produce the resulting composite pixels.

  • These commands overlay the pixels in two or more channels. Thus, the images used for calculations must have the same pixel dimensions.

Blend channels with the Apply Image command

The Apply Image command lets you blend one image’s layer and channel (the source) with a layer and channel of the active image (the destination).

  1. Open the source and destination images, and select the desired layer and channel in the destination image. The pixel dimensions of the images must match for image names to appear in the Apply Image dialog box.
    Note:

    If the color modes of the two images differ (for example, one image is RGB and the other is CMYK), you can apply a single channel (but not the source’s composite) to the destination layer’s composite channel.

  2. Choose Image > Apply Image.
  3. Choose the source image, layer, and channel you want to combine with the destination. To use all layers in the source image, select Merged For Layer.
  4. To preview the results in the image window, select Preview.
  5. To use the negative of the channel contents in the calculation, select Invert.
  6. For Blending, choose a blending option.

    For information on the Add and Subtract options, see Add and Subtract blending modes. For information on other blending options, see Blending mode descriptions.

  7. Enter an Opacity value to specify the effect’s strength.
  8. To apply the results only to opaque areas in the result layer, select Preserve Transparency.
  9. If you want to apply the blending through a mask, select Mask. Then choose the image and layer containing the mask. For Channel, you can choose any color or alpha channel to use as the mask. You can also use a mask based on the active selection or the boundaries of the chosen layer (Transparency). Select Invert to reverse the masked and unmasked areas of the channel.

Blend channels with the Calculations command

The Calculations command lets you blend two individual channels from one or more source images. You can then apply the results to a new image or to a new channel or selection in the active image. You cannot apply the Calculations command to composite channels.

  1. Open the source image or images.
    Note:

    If you are using more than one source image, the images must have the same pixel dimensions.

  2. Choose Image > Calculations.
  3. To preview the results in the image window, select Preview.
  4. Choose the first source image, layer, and channel. To use all the layers in the source image, choose Merged For Layer.
  5. To use the negative of the channel contents in the calculation, select Invert. For Channel, choose Gray if you want to duplicate the effect of converting the image to grayscale.
  6. Choose the second source image, layer, and channel, and specify options.
  7. For Blending, choose a blending mode.

    For information on the Add and Subtract options, see Add and Subtract blending modes . For information on other blending options, see Blending mode descriptions.

  8. Enter an Opacity value to specify the effect’s strength.
  9. If you want to apply the blending through a mask, select Mask. Then choose the image and layer containing the mask. For Channel, you can choose any color or alpha channel to use as the mask. You can also use a mask based on the active selection or the boundaries of the chosen layer (Transparency). Select Invert to reverse the masked and unmasked areas of the channel.
  10. For Result, specify whether to place the blending results in a new document or in a new channel or selection in the active image.

Add and Subtract blending modes

The Add and Subtract blending modes are available only for the Apply Image and Calculations commands.

Add

Adds the pixel values in two channels. This is a good way to combine non-overlapping images in two channels.

Because higher pixel values represent lighter colors, adding channels with overlapping pixels lightens the image. Black areas in both channels remain black (0 + 0 = 0). White in either channel results in white (255 + any value = 255 or greater).

Add mode divides the sum of the pixel values by the Scale amount, and then adds the Offset value to the sum. For example, to find the average of the pixels in two channels, add them, divide by 2, and enter no Offset value.

The Scale factor may be any number between 1.000 and 2.000. Entering a higher Scale value darkens the image.

The Offset value lets you lighten or darken the pixels in the destination channel by any brightness value between +255 and –255. Negative values darken the image; positive values lighten the image.

Subtract

Subtracts the pixel values in the source channel from the corresponding pixels in the target channel. As with Add mode, the result is then divided by the Scale factor and added to the Offset value.

The Scale factor may be any number between 1.000 and 2.000. The Offset value lets you lighten or darken the pixels in the destination channel by any brightness value between +255 and –255.

 Adobe

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