I must admit, I like Photoshop. In fact I'm fascinated by the kind of changes a skilled person can make to a photograph, especially the magazine retoucher's work on people.

Here is my rather less skilled attempt at retouching a photo from last month's Digital Photographer magazine. It took me about four hours to do this. There are hundreds of tiny changes and tweaks adding up to approximately 24 major differences. Can you spot them all? (You might want to click through to a larger size.)

For demonstrations of better Photoshop skill these are worth a watch:

• The magic of Photoshop
• Extreme (Photoshop) Makeover
• Retoque com Photoshop
• Extreme Photoshop Retouch
• The camera never lies (BBC Radio 1 Surgery)