LAYERS FOR DIGITIZERS
Presentation by Kathy Cooley
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Using layers gives flexibility. It gives you the ability to isolate different parts
of an image on layers which can then be edited.

Photoshop needs a layer to operate and by default calls it “Background”.
However, you are unable to do many things to the “Background” that can be
done to layers:

• Change stacking order

• Change blending mode

• Change opacity

• Change fill percentage

• Attach a mask

• Embellish it with layer effects/styles

• Must be fully opaque and cannot contain transparent pixels

A document does not have to contain a “Background”. You can double click
on it and change the name or go to Layer > New > Layer from Background.

Conversely, any layer can become a “Background” by simply going to Layer
> New > Background from Layer.

Good idea to duplicate your “Background” before editing. If you make a
mistake, you can always go back to the “Background” or use the History
Brush from the “Background”. Try to use adjustment layers whenever
possible as it preserves the original pixels and you can always readjust. Use a
new layer to add color or tints and sharpen. Name your layers.

Always check your layer selection to make sure you are working on correct
layer.

To select more than one layer:

• If consecutive – click first layer and then Shift-click last layer

• Not consecutive – Command-click (Control-click) individual layers

• Similar kinds (e.g., image, shape, adjustment) – Control-click (Right-click)
one and choose “Select Similar Layers”.

Formats that save layers (must check “Layers” box):

• Photoshop PDF

• Photoshop

• Large Document Format

• TIFF

All others automatically flatten the layers.

Layers are controlled via the Layer Palette. Let’s look at the icons in the
Layer Palette. At the top we have:

• Lock Transparent

• Lock Image

• Lock Position

• Lock All

At the bottom we have:

• Link Layers

• Layer Style

• Layer Mask

• Create fill or Adjustment Layer

• Create New Group

• Create New Layer

• Delete Layer

At the top right there is an available pull-down menu and some of these can
also be accessed by Control-click (Right-click) while others are duplicates of
the icons at the bottom of the palette.

Align two layers – Click a layer, hold Command (Control) and click on 2nd
layer. Edit > Auto-Align Layers. Set to Auto and click OK.

Align objects on two or more layers – Select layers, select move tool (V) and
use option bar at the top to choose your choice of alignment.

15-Second Fix for underexposed/overexposed images:

• Duplicate layer

• Blending Mode > Screen – lightens (underexposed)

• Blending Mode > Multiply – darkens ( overexposed)

FYI:

• Merge down preserves transparency (except to the “Background”) while
flattening does not.

• Drag and drop layers between open documents. Suggested use – When you
have a group of photos taken in similar lighting, make an adjustment
correction layer then drag to others.

• Option/Delete (Alt./Backspace) fills layer or selection with black
(foreground color).

• Command-J (Control-J) duplicates selected layer

• When switching color modes, click “Don’t Flatten” or “Don’t Merge” to
preserve layers.

• Layer Groups are like folders – Can move, rotate, scale, duplicate, restack,
lock/unlock, hide/show simultaneously.