Does anyone have any comparison info on the picture quality of these 2 lenses? Is the 100 -300 Canon lens significantly better? I plan to use the lens for high school sports.

-- sue labeaume (slabeaume@hotmail.com), October 16, 2000

Answers

I can't speak for the optical quality of the Tamron, but I have owned two of the Canon 100-300USM lenses. It's a good quality consumer optic: really sharp and contrasty from 100 to 200mm and a bit softer at 300 (but good enough for nice 11 x 14 enlargements if you use a good tripod). However, I do know the Canon has a real advantage over the Tamron in AF: Canon's ultrasonic motor (USM) is totally silent and very fast. The rear element focus and USM combo rips. The Real-time manual focus override of the Canon is the best advantage yet (you can manual focus without fliping the manual focus switch and without releasing exposure lock.

Avoid the cheaper Canon 75-300. AF is very slow and it doesn't have real time manual focus.

-- Puppyface (puppyface@aol.com), October 16, 2000.

I wouldn't buy any of these if I was looking for the best in image quality. None of them have it. But if you're looking for acceptable quality at an affordable price, then any of them would do. They are fairly even in sharpness.

The Canon 100-300 USM cost's more because it's built better, doesn't rotate the filter ring, focuses faster and offers full time manual focusing. If you are looking at a lens for sports shooting, that last feature could be very important after you tried it.

-- Jim Strutz (jimstrutz@juno.com), October 17, 2000.