Canon EF 300mm f4L

Fall Leaf -- Canon 1D Mark II & EF 300mm f4L @ f4. Click for larger.

It's not an understatement that it was Canon's wickedly fast focusing USM telephoto lenses coupled with the EOS-1 that wrestled the sports photography market since the film days from Nikon's long time dominance, until the the Nikon D3 and its revamped AF-S based telephoto lenses.  Nikon's screw drive focusing lenses were no match for Canon's super quiet and fast ultrasonic motors based lenses. Unfortunately for most of us, fast pro telephoto lenses like 300mm and 400mm f2.8  are just too darn expensive. But, there are in-between lenses, like the EF 300mm f4L, 400mm f5.6L.  These two lenses were designed for photo enthusiasts who can not justify spending $7,000 on a 300mm f3.8L, or $11,000 for a 400mm f2.8.  They are wildly popular, due to it's lower prices and most of all, superior optical performance.

I had the 300mm f4L, the original non-IS version.  It was the sharpest telephoto lenses I used, other than the ungodly sharp 200mm f1.8L.  It is light and fast focusing.  Did I mention that it is sharp?  I later traded it for an IS version and found that it was not as sharp as the non-IS copy, and add to the reason that I don't use tele lenses much, and later sold it.  I highly recommend the non-IS version of the 300mm f4L, if you are looking for a telephoto lens with a smaller budget.  These lenses can be had in the used market for $500 to $700 depending on condition.