I have rasterized an object in Illustrator, so it is embedded. I want to enhance it with photoshop, but I don`t know how to convert it to link.
Oh, I think I may have worked out what you're trying to do....
You've rasterized a set of objects in Illustrator. When you do this the image shows up as an embedded image in the Links Panel.
You want to alter this set of rater objects with Photoshop.
And you want to convert the embedded image to a linked image in the Links Panel.
Simply select and copy the raster objects.
That should replace the rasterized embedded image with a link to the Photoshop image.