Set blend mode of current layer in a Photoshop document

Scripting Forums AppleScript | Mac OS X
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#1

What i have so far is:

tell application “Adobe Photoshop CS4”
set blend mode of current layer to screen
end tell

That throws the error:

Adobe Photoshop CS4 got an error: Can’t set current layer to screen.

I’m running OS X 10.5.8

any one got any ideas?

#2 
tell application "Adobe Photoshop CS4"
	tell current document
		set blend mode of current layer to screen
	end tell
end tell