I have owned one of these lenses for over 10 years and it is sensational. Great autofocus and fabulous bokeh. Wonderful wildlife lens especially for birds. Works well with my Mk3 1.4x TC not great with 2x and MF only with the latter. Yes it is on the heavy side but hardly surprising.

Quick Focus; Rugged; Sharp Focus

No matter what if you are in the back row and your son on the stage at a school play, your picture will be prefect and it will look like you were in the front row.

This is a horrible way to spend your money!! I got this lense but for how much money you spend (a lot) you dont get much back, sure for a while you can zoom in really far and see things like you have never seen them from a camera before but after a while even that ends up getting messed up...

zooms in far

images (after lots and lots of use) can be distorted..

There is nothing like the arrival of a new Canon Super Telephoto Lens to bring the excitement of Christmas to any time of the year. And the hit on the credit card from this lens is considerably larger than the hit from most households' Christmas expenditures.

The arrival of the new Canon EF 800mm f/5.6L IS USM lens was a case of perfect timing as within a few days I'd be on the road for a couple of weeks photographing the abundance of wildlife at the Blackwater Refuge.

The tripod mounting bracket is fully integrated into the main barrel and rotates rather cleverly internally after a locking knob has been released. There are click-stops at 90-degree intervals which makes switching orientations a lot easier from behind the camera.

It's an excellent lens in every regard. Compared to the 200 f2L IS (which I have) it falls a bit short in the CA performance. But if you've used the 200L IS this is something you'll fuss about with every lens you use and unfortunately the 800L IS isn't immune to it.

Everything

Nitpicking a bit but CA