Macro Photography: Shooting Macro with the Canon 7D and extension tubes Vs close up filters

I took some nice pics today using my Canon 7D and 50mm F1.8 lens reversed on a set of extension tubes. For a comparison in magnification I also have a beetle that I took with the extension tubes and then with the 50mm F 1,8 lens and a set of magnification filters. I used Kenko close up filters with the No 1, No2 and No 3 filters stacked on top of each other. This allows you to focus much closer with full aperture, shutter and auto-focus control, but you can't focus as close as with the extension tubes.

I have a also included a photo of a match head on a canon lens carp to show the difference in magnification between the close up filters on a 50mm lens and a set of manual extension tubes and a 50mm F1,8 lens reversed on top, As you can see, the amount of magnification is dramatic, and this was not even a full set of extension tubes....