Just a public service announcement: Canon's MP-E 65mm macro lens has a ribbon cable that connects the aperture assembly to the contacts on the lens. With repeated use that cable will break causing the following symptoms:
- You'll hear a "crunching" noise, kinda like metal scraping against metal (probably the aperture blades not moving in unison and binding up).
- "Error 01 , communication between camera and lens faulty. Clean lens contact" will be displayed on the LCD.
- Changing the magnification ring may temporarily "fix" the problem. At some magnifications the lens might work, and at others it might not. Or the lens will just fail hard with the Error 01 message on the LCD.
I have had to send my MP-E 65mm in to a Canon service center twice in the roughly eight years I've owned it, with the cable breaking once every four years (almost exactly four years apart between the first and second repair). Keep in mind that I'm a pretty heavy user of the lens, so I don't think that it's inherently faulty.
Both times the MPE-65mm broke I used an EF-S 60mm macro lens + extension tubes while waiting for it to be repaired. I have since labeled that combo the Poor Man's MPE-65mm. A full set of tubes will only get you to about 3x, but it's probably one of the easiest ways to shoot above life size if you don't have the MP-E 65mm (or don't want to pay for one). You can also use the lens on any Canon camera as long as you have an extension tube attached. You'll lose infinity focus, but that's not what a macro lens is for anyway
Personal note: I absolutely loathe macro lens reviews when the reviewer justifies buying the glass because you can also use it to take portraits... of people. I also think it's pretty darn short sighted to gauge the sharpness of a macro lens when it's focused at infinity. Just stop...