Wow was I surprised on my first shoot with this lens. I had a Great Blue Heron fly directly at me and not having my tripod on though that the pictures would turn out shaky but the were crisp and clear. A very nice lens and focus is very quick and without any hesitation.

I've only used it for a couple of days but it seems to be in just as good a condition as advertised. No scratches, no visible damage. Works great. Good stuff. Fun fact. I chose the seller with the best lens picture.

Just purchased this lens and have spent time out birding. I've used it with and without an EF Extender 1.4x, and both hand-held and on a solid tripod. I'm very pleased: without the extender you can (with large hands and steady arms) shoot hand-held for quite a while.

This lens is one of the great values in photography. It is super sharp and does a great job of bringing the action to you. While it does not have image stabilization, it is light enough to hand hold and with some practice you can get great shots.

Image quality; weight; build quality

No image stabilization; maximum aperture f/5.6

I was looking at purchasing the Canon 100-400mm zoom then convinced myself I would be mainly using it at the 400mm end so why waste money when you can buy the Canon 400mm f5.6L for half the price Received my lens just over a week ago and have not used it much beyond the wildlife in my garden.

My previous 100-400mm L IS USM lens seemed to produce shots which lacked sharpness, particularly noticeable in reduced fine feather detail when photographing birds. This 400mm f5.6 prime lens is much crisper and gives much improved results.

Lightweight; Quick Focus; Sharp Focus; Strong Construction

No Image Stabilisation

I'm using this lens and an EOS 700D on an internet controlled astrograph. The build and the image quality over the entire field are both absolutely superb. Ultimate picture quality appears to be limited by the camera sensor, rather than the lens. Just amazing. Next, a x2 extender.

A very fast focusing lens on canon. MTF chart of the lens says all about the picture quality

I bought this for a trip to BC/Alaska, and it's my first Canon L lens. It may have cost me an arm and a leg, but it is solidly built and focuses very fast. I bought a monopod at the same time but it could really do with a pistol grip screwed into the lens's tripod bush when you're shooting hand-held...

Pros: I have had numerous favorable photography gear purchases from buydig.com and my new Canon 400mm 5.6L is no exception. It's a sharp, telephoto lens with a wonderful bokeh not to mention it is rather light weight. So it's easy to carry by hand vs. requiring a tripod.