the 100mm f2 is a useful lens. the focal length and fast apperture make is perfect for portraits, and compared to the 70-200 it's a lot less tiring to use. being a telephoto with an f2 apperture makes it appropriate for things such as sports, where an f2 apperture can let in twice the light of a 2.8 lens, and give you shutter speeds that are more suitable for action sports (IS doesn't help much when your subject is moving) For the speed you do give up some flexibility, if you're not in the right place when you frame your shot then too bad, because you can only zoom with your feet. Shooting with 2 bodies is good practice for professionals using prime ...  Read the complete review

If you're choosing a fixed focal length lens for portrait photography, there are several options from Canon. There are 50mm/1.8, 50mm/1.4, 85mm/1.8, 100mm/2.0, 135mm/2.8 - I only name affordable ones. There are also some alternatives from Sigma: there are 50mm, 70mm and 105mm, all f/2.8. Tamron has 90mm/2.8, and Tokina has 100mm/2.8. First of all, several words about portrait lenses in general. Why do you need a fixed focal length lens for portraits? The answer is simple: a zoom lens will never beat a fixed-focal in quality. Also, it's nice to have a fast lens (with wide maximum aperture), and fixed-focals are usually faster then zooms. The wider you open the ...  Read the complete review