Displacement Maps Photoshop

Photoshop CS4 won’t let me use displace filter – why and how do I change that?

well, the title pretty much says everything… i already used the displacement map feature in an earlier version of PS without any trouble but now I can’t figure out why filters->distortion->displace is greyed out!
the file i want to use the displacement on got transparent background but i already tried pictures with backgrounds =(
i’m working with 16-bit RGB files and the only distortion filter i may use is lens correction – anybody got an idea?

Displace will only work on 8bit or lower. You’ll have to convert it.

Image > Mode > 8bit.

It will be visible again.

Photoshop Tutorial Displacement Map

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