Embedded CMYK TIFF Graphics Are Exported As RGB and the Picture Includes an Alpha Channel (825923)

SYMPTOMS

In Publisher, when you export a picture that uses the Tagged Image File Format (TIFF), the exported picture uses the red-green-blue (RGB) color model. Additionally, an alpha channel is added to the image data of the exported picture. This behavior occurs even when the original picture uses the cyan-magenta-yellow-black (CMYK) color model and does not have an alpha channel.

CAUSE

This problem occurs when you export the picture by using either of the following two methods:

In Graphics Manager, you select the picture and then click Save as Linked Picture.
You right-click the picture and then click Save as Picture.

Publisher uses a TIFF export filter that saves files as RGB with one alpha channel.

WORKAROUND

If you have to edit an embedded CMYK image, you must obtain a copy of the original graphic and then work with that image. If the original graphic is unavailable, open the picture in a photo editing program (such as Adobe Photoshop) after you export the picture from Publisher, and then convert the picture back to CMYK.

MORE INFORMATION

In Publisher, there are two methods for converting an embedded graphic in an external graphic file (besides copying and pasting). Both of these methods work well when you have to convert an embedded RGB picture to CMYK.

Notes about alpha channels

The TIFF file format supports additional color channels besides RGB or CMYK. These additional channels are named alpha channels. When you import a TIFF file in Publisher and that TIFF contains alpha channels, Publisher uses the first alpha channel as a transparency mask. The TIFF image appears in Publisher with a transparent background.
If you export a rectangular object as a TIFF file, the alpha channel is blank. If you export an irregular object, the alpha channel contains the outline of the object.