Adobe 13101332 - Photoshop - Mac User Manual page 276

Adobe Photoshop Help
Using Help | Contents
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 Select Preview to preview the results in the image window.
5 Select Invert to use the negative of the channel contents in the calculation.
6 For Blending, choose a blending option.
For information on the Add and Subtract options, see
blending modes" on page
a blending mode" on page
7 Enter an opacity to specify the effect's strength.
8 Select Preserve Transparency to apply the results only to opaque areas in the result
layer.
9 Select Mask if you want to apply the blending through a 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. (See
(Photoshop)" on page
Using 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.
To use the Calculations command:
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 Select Preview to preview the results in the image window.
4 Choose the first source image, layer, and channel. To use all the layers in the source
image, choose Merged for Layer.
5 Select Invert to use the negative of the channel contents in the calculation. For
Channel, choose Gray to get the same effect as would be obtained by converting the
image to a grayscale image.
6 Choose the second source image, layer, and channel, specifying further options as
described in step 5.
7 For Blending, choose a blending mode.
For information on the Add and Subtract modes, see
blending modes" on page
blending mode" on page
8 Enter an opacity to specify the effect's strength.
Using Help | Contents
| Index
277. For information on other blending options, see
241.
"Using channel calculations to blend layers and channels
275.)
277. For information on other blending modes, see
241.
| Index
Using Channels and Masks
Back
"About the Add and Subtract
"About the Add and Subtract
Back
276
"Selecting
"Selecting a
276