I have been using this lens for more than a month now. Its really exciting to see distant birds and wild animals so close thro' the image finder. AF is very fast.

Consistent Output; Durable; Easily Interchangeable; Fast / accurate auto-focus; Nice Bokeh; Rugged; Strong Construction

Heavy

What can I say, superb image quality with ultra long reach The ultimate wildlife lens, lighter than the 600mm and it fits (just) in my AW Rover bag so I can take it as hand luggage Add a 1.4x on a 1d body and you have autofocus (centre only) to an incredible 1456mmm equivalent Expensive but you know...

the pros of this lens are well documented in various on line reviews,all i will say is that its not cheap but its worth the money. you really do get what you pay for.its easy to manage thanks to its relative lightweight and it produces very sharp images for a super telephoto lens,F5.6 and F8 are the...

SUPERB LENS,VERY LIGHT,VERY SHARP AND EXQUISITE CONSTRUCTION

None really,F4 would be sweet but it would then weigh a tonne.

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