Originally Posted by
ktuli
Nick, Amanda,
Actually, your understanding here is reversed. 1:1 macro is indeed life size... however, 5:1 is 5 x life size, so a subject can be magnified 5 times its real size on the sensor.
There also also lenses on the market that are labeled as macro but only get 1:2 (which is 1/2 life size) or 1:3 (1/3rd life size). I would not consider these to be true macro lenses. These are quite often zoom lenses - where true 1:1 lenses are usually primes (as the others have said).
The Canon MP-E65 is a specialty lens and is full manual and basically has bellows/extension tubes built in. This is not really something you want to try as a first macro lens or to be used for portaits.
As to picking the lens, the other posts here seem to have that covered pretty well. I just wanted to make sure that I shared the info about the 1:1, 5:1, and 1:2 designations.
Hope this helps!
- Bill