Adobe Photoshop

Aka: Adobe Photoshop

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II. Precautions: Non-Medical

  1. Not for Medical Care
  2. The author uses several software packages and programming languages to develop FPnotebook content
  3. For convenience, a dozen pages in FPNotebook are dedicated to quick notes on content creation

III. Technique: Anatomy

  1. Draw Blue Bursa Sac
    1. With pen draw a shape
    2. Add an adjustment fill layer - gradient (uses pen-drawn shape)
    3. Choose gradient #004080 to #7fbfff
    4. Add fx - outer glow to layer: Color #0061c2, spread 7, size 18

IV. Technique: Layers

  1. Create selection from mask
    1. Ctrl-click on Mask Icon on Layer (alt-click allows for editing the mask)
    2. Also works with a selection outline of object pasted onto layer
  2. Copy selected part of image to a new layer
    1. Ctrl-J (or Ctrl-Alt-J to name it)
  3. Replace a layer mask with another
    1. Click on the new layer mask to use and press alt while dragging to the mask to replace
    2. If the layer had no prior mask, this mask creates a new one for the layer
  4. Merge all layers onto a new layer
    1. Alt-Ctrl-Shift-E (only way to do this, there is no menu option)
  5. Create New Layer
    1. Ctrl-Shift-N
  6. Layer Modes
    1. Multiply
      1. Darkens (consider in compositing)
    2. Screen
      1. Lightens
  7. Duplicate Layer
    1. Right click on image or layer and choose duplicate layer
    2. Allows layer to be duplicated to any open document
  8. Apply layer to one below
    1. Alt-click between the two layers until you see icon (box with arrow down)

V. Technique: Selection

  1. Quick Mask (Q)
    1. Use smudge tool for soft edges
    2. Press tilda (~) to toggle on and off the ruby-lith image (shows only the black/white mask)
  2. Editing Mask
    1. Alt-Click the layer mask thumbnail to see mask in black and white
    2. Set default colors with "D" (white as foreground, black as background)
    3. Use the brush tool (100% hardness, 100% opacity) and paint mask with black to conceal, white to reveal
    4. Select areas (e.g. marquee, lasso) and backspace to fill selected mask area with background black
    5. Select areas (e.g. marquee, lasso) and alt-backspace to fill selected mask area with foreground white
    6. Invert the mask with Ctrl-I
    7. Check mask by using magic wand tool with threshold set to 0
      1. Click in blacks with magic wand, invert selection and paint any residual selected areas with black
      2. Click in whites with magic wand, invert selection and paint any residual selected areas with white
  3. Other compositing tools (for adjusting selections)
    1. Smudge Tool
      1. Smudge margins in slightly
  4. Refine Mask
    1. For compositing, use a combination of feather and shift edge
      1. Feather: 0.5
      2. Shift-Edge: -50
      3. Adjust contrast to increase edge definition as needed
  5. Selection modifications
    1. Click/drag to start new selection
    2. Shift + click/drag to add selection
    3. Alt + click/drag to subtract selection
    4. Shift + alt + click/drag to intersect selection
  6. Tools to get basic selection with edge detection
    1. Precautions
      1. Edges will be imperfect (use threshold tool set to 0 and 255 to see this)
      2. Use the refine mask/edge without changing radius/auto
        1. Increase smooth and contrast in equal ammounts to remove irregularities
    2. Tools (use shift to add to selection, alt to subtract from selection)
      1. Magic Wand
      2. Quick Selection
    3. Selection Menu
      1. Set-Up
        1. Deselect selection, Ctrl-D, before applying these
        2. If limiting sample to a single layer, ctrl-click the layer first
      2. Color Range
      3. Focus Area
    4. Magnetic Lasso
      1. Adheres to edges, automatically laying down points while you move around object
      2. Click "backspace" to remove a point
      3. Click to create a point
  7. Adjusting selection
    1. Transform selection (free transform for selections)
      1. Transform Selection (selection menu)

VI. Technique: Transformation

  1. Precautions
    1. Each application of free transform re-writes layer pixels (but not vector based shapes)
      1. Avoid applying free transform to the same pixel-based layer more than once
      2. Smart objects and vector-based objects may be transformed multiple times
    2. Some effects are permanent modifications when using standard layers
      1. Smart objects and their applied filters remain editable (e.g. filters such as gaussian blur, camera raw)
    3. Masked smart objects can not be transformed
      1. Click the link icon between the smart object and mask to disconnect
      2. Transform the smart object and then click the mask link icon to reapply the mask
  2. Free Transform Tool (Ctrl-T or to create a copy at same time, Ctrl-Alt-T)
    1. Skew
      1. Ctrl-click and drag
    2. Skew opposite sides simultaneously
      1. Ctrl-Shift and drag
    3. Perspective transform
      1. Ctrl-Shift-Alt and drag
    4. Warp Mode
      1. While working in Free-Transform mode, click on warp mode button at upper right

VII. Technique: Camera Raw

  1. Cross-functionality with Photoshop
    1. Open as smart object in photoshop
      1. When DNG or raw file is open in camera raw, hold shift and click "open object"
      2. Double click thumbnail to open again in camera raw
      3. To duplicate a smart object layer, right click image and select "New Smart Layer via Copy"
        1. Avoid Ctrl-J for this, as will simply copy a layer but modify the sam underlying smart object
  2. HSL adjustments
    1. Use the HSL Grayscale tab with the targeted ajustment tool
    2. Select the saturation sub-tab
      1. Click over colors to adjust in the image and slide mouse left or right to modify
    3. Select the luminance sub-tab
      1. Increase or decrease luminance as needed
    4. Less commonly, hues may also be adjusted
  3. Contrast adjustments
    1. Contrast affects all pixels
      1. Increasing contrast increases brightness of highlights and darkness of shadows
      2. Increasing contrast spreads the histogram out
    2. Clarity affects edges
      1. Increases contrast between highlights and shadows adjacent to one another
  4. Identifying clipped whites or blacks
    1. Hold Alt while dragging the whites slider (clipped whites will be shown on black background)
    2. Hold Alt while dragging the black slider (clipped colors will be shown on white background)
      1. Complimentary colors are shown of the clipped channel (e.g. yellow indicates clipped blue channel)
      2. Normal to see some clipping of various colors
      3. Black areas suggest clipping of all colors and this should be corrected
  5. Setting white balance when neutral color in image is difficult to find
    1. Turn vibrance to 100%
    2. Select the white balance tool (I, eye dropper)
    3. Click on or drag over a white or light gray object
    4. Decrease the vibrance to a reasonable setting

VIII. Technique: Saving

  1. Saving for web
    1. Save for Web (legacy) still offers the most options
    2. Always choose "convert to sRGB"
    3. Choose JPG for photos and PNG 8 for illustrations (PNG-32 for broad color range >>256)

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