Adobe Photoshop CS4 - Manual (Page 305)

298 USING PHOTOSHOP CS4
Layers
Last updated 1/10/2010
Setting opacity and blending
Specify opacity for a layer or group
A layer’s opacity determines to what degree it obscures or reveals the layer beneath it. A layer with 1% opacity appears
nearly transparent, whereas one with 100% opacity appears completely opaque.
Note: You cannot change the opacity of a background layer or a locked layer. You can, however, convert a background
layer into a regular layer, which does support transparency. See “
Convert background and layers ” on page 285.
1 Select a layer or group in the Layers panel.
2 Do one of the following:
• In the Layers panel, enter a value in the Opacity text box or drag the Opacity pop-up slider.
• Choose Layer > Layer Style > Blending Options. Enter a value in the Opacity text box or drag the Opacity pop-up
slider.
• Type a number indicating the percentage of opacity.
Note: To view blending options for a text layer, choose Layer > Layer Style > Blending Options, or choose Blending
Options from the Add A Layer Style icon at the bottom of the Layers panel menu.
Specify fill opacity for a layer
In addition to setting opacity, which affects any layer styles and blending modes applied to the layer, you can specify a
fill opacity for layers. Fill opacity affects pixels painted in a layer or shapes drawn on a layer without affecting the
opacity of any layer effects that have been applied to the layer.
For example, if your layer contains a drawn shape or text that uses a drop shadow layer effect, adjust the fill opacity to
change the opacity of the shape or text itself without changing the opacity of the shadow.
❖ Do one of the following:
• In the Layers panel, enter a value in the Fill Opacity text box or drag the Fill Opacity pop-up slider.
• Double-click a layer thumbnail, choose Layer > Layer Style > Blending Options, and enter a value in the Fill Opacity
text box or drag the Fill Opacity pop-up slider.
Note: To view blending options for a text layer, choose Layer > Layer Style > Blending Options, or choose Blending
Options from the Add A Layer Style icon at the bottom of the Layers panel. Enter a value in the Fill Opacity text box.
Specify a blending mode for a layer or group
A layer’s blending mode determines how its pixels blend with underlying pixels in the image. You can create a variety
of special effects using blending modes.
By default, the blending mode of a layer group is Pass Through, which means that the group has no blending properties
of its own. When you choose a different blending mode for a group, you effectively change the order in which the
image components are put together. All of the layers in the group are put together first. The composite group is then
treated as a single image and blended with the rest of the image using the selected blending mode. Thus, if you choose
a blending mode other than Pass Through for the group, none of the adjustment layers or layer blending modes inside
the group will apply to layers outside the group.