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

With the use of my lenshide and this Super Telephoto lens I did capture photos of wildlife that is so crisp and stunning. I pair this one with my canon 1DX because I observed that my 1DX give me more freedom with the light in low light situation. However, I sometimes I used also my 5DS.

A great performing lens when it comes to Wildlife and news photojournalism. Of course you can use this lens for sports as well. But it might be a bit tight standing at the field, because you might be too close.

Resolution has always been my highest priority and this lens certainly is the best. The auto-focus features are superb. After using the 600mm f/4 L lens for years trading it in for the 800 was the best trade I've ever made.

Fast auto-focus; Superior build quality; Super-sharp images

wish it had a larger aperture

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.

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

The images produced at f5.6 are sharper than anything from any lens I've ever seen. Color and contrast are both excellent. Focus is fast and accurate. A keeper!

Really brings distant wildlife up close. Birds in flight are fantastic.

Consistent Output; Fast / accurate auto-focus; Sharp; Strong Construction

Really brings distant wildlife up close. Birds in flight are fantastic.

Consistent Output; Sharp; Strong Construction; Fast / accurate auto-focus

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...