Wow...very creative. And it seems to be working for you, so Job Well Done!Robin: I just checked my raw image and I've noticed that it's cropped but just for adjusting the angle of the photo. The watch was rotated a little. If you want i can upload an untouched version of the photo.
It is true that you can free the lens and control the aperture with the help of the DoF button but in the way that i modified the lens I can control the aperture when it is reversed, as I would do with a normal lens.
Basically I dismantled the mount of the lens, I have de-soldered the electrical contacts from the circuit board of the lens. I sawed off the mount of the lens (the protruding bit of the EF-S mount) and glued it the other way (to the front element of the lens) and with the help of an old floppy/ata/ide cable i have soldered back the electrical contacts. In that way the camera can control the aperture of the lens as it would do with a normal lens.
The lens had problems (the focus control ribbon ripped apart) and it was very cheap and I didn't want to repair it so I gave it a try
I will post a picture with the lens.
Sorry for my bad English