Transparency "added" to TIFF images

[oscillator]

Acrobat X reports that images in my PDF use transparency ("Transparency used (soft mask in image)") but they are saved as TIFFs from GIMP without any alpha channel.

Strangely enough, this only happens for a few of my GIMP TIFFs.

What causes this behavior?

Staffan

[oscillator]

Ok, my fault. I had introduced an alpha-channel during the GIMP editing process.

Sorry.