How to select a difference of two layers?
Consider the following two files.
Background with some content on top:
How do I get a flat image that is content-background? ie. the result should be white text with the blood stains on a transparent background.
The underlying issue that I am trying to solve:
The layers "Layer 27 copy 3" and "Layer 55" (the blood stains) use "multiply" blending mode, therefore simply merging these with the text will result in:
- Turn off visibility for paragraph layer ("Each correct answer will...")
- New Layer above all other layers (Command/Ctrl-Option/Alt-Shift-N)
- Merge Visible (Command/Ctrl-Option/Alt-Shift-E)
- Turn off visibility for all other layers
- Select all (Command/Ctl-a)
- Copy (Command/Ctrl-c)
- Add Layer Mask
- Select Layer Mask (Command/Ctrl-)
- Paste (Command/Ctrl-v)
- Adjust levels to bring up the white nad red and reduce the black.
- Turn on visibility fo the paragraph layer ("Each Correct Answer will...")
- Save for web
To retain all the blood - on or off text
- Set both the blood layers to Normal.
- Remove the mask on the one layer.
- Merge the two layers
- Choose Select > Color Range and click a white area of the layer
- Hit OK
- Inverse Selection (Select > Inverse)
- Add layer mask
- Set layer to multiply.
This leaves you with this...
(grey background used to show transparency)
You can then further mask the blood if you'd like.