Clipping mask from complex shape InDesign

Question

this may be a duplicate question but I can't fix this problem with the solutions I've found.

I have three images in InDesign:

• Background 1
• Background 2
• Mask Image (complex silhouette of a forest)

I want to keep Background 1 as the main background, and clip Background 2 into the shape of the Mask Image. I've removed the (previously white) background of the Mask Image in Photoshop to create an entirely transparent background, and added an alpha channel.

So, it should be a case of Ctrl-X on Background 2, then select the Mask Image and Paste Into.

Except... this doesn't work. Background 2 does indeed go into the Mask Image's frame, but it doesn't take the shape of the trees. Does anyone know what I'm doing wrong?

Answer 1

You must at first to convert the alpha channel of the Mask image to InD clipping path (Object > Clipping Path > Options > Alpha)

Next convert the clipping path to a frame (Object > Clipping Path > Convert Clipping Path to Frame)

Now you can paste your photo into the image which is actually a frame.

Warning: The pasted photo takes its full size. It does not help that you possibly copied into the clipboard a placed and scaled copy. The size in centimeters will be the original size taken from photo metadata. Fortunately scaling is possible inside the frame, no matter how complex is it.

An example:

The black Z is a PSD image; one layer, a black painted Z on transparent background, no attempt especially to add an alpha channel, only painted the Z on the checkerboard

The orange outline appeared after converting the alpha channel to clipping path

A copy was made. The whole Z was selected with the normal black arrow tool, copied and pasted. Object > Clipping Path > Convert Clipping Path to Frame was applied.

The placed and squeezed photo was copied to the clipboard and pasted into the new frame. See its different size. The squeezing didn't have any effect to the pasted copy.