Thanks Roger, great suggestion. Do you know if there is a way to put a drop shadow on the "first" border using this method?
Well, I didn't before your question, so it was a challenge. [img]images/icons/smile.gif[/img] This was the method I worked out. It requires layers, so will only work with 8-bit images.
1. Open image
2. Duplicate background layer
3. Set background colour to white
4. Select original background layer
5. Increase canvas size with relative checked by enough to include shadow
6. Select background copy (dupe layer)
7. Layer>Layer Style>Drop shadow - fiddle with settings as required
8. Set background colour to black
9. Select background layer
10. Increase canvas size again
There may be an easier way, but this works and could be recorded.