Would prefer a f3.5 version of the DO lens. Because of price, plus size and weight, It would soon become the most popular telephoto for wildlife, just as it was for many years with Nikon.

I am a huge fan of my Canon 600mm f/4. The sharpness of that lens continues to blow me away. I realized that over the past few years all my wildlife pictures were taken between 400-800mm. My next in line lens fixed tele-lens was an old 300mm Sigma f/2.8 without IS.

The EF 400mm f/4 DO IS II USM lens delivers brilliant high-speed performance for professionals with minimal glare and superb image quality. Taking advantage of the best in lens technology, it features gapless dual-layer diffractive optical elements for improved diffraction efficiency with reduced...

I chose this lens as a compromise to get the maximum focal length against weight (and cost) as I tend to walk around when shooting wildlife rather than use a tripod or monopod. The 500mm f/4 is just too heavy for me to walk round with or hand-hold at eye-level for long periods.The 400mm f/4 DO can...

Relatively lightweight; f/4 max aperture allows a x2 Extender to be used

Expensive; Focus not the fastest with a x2 extender

When you think of a super telephoto lens, especially one with a wide f/4 aperture, a few words come to mind: big, heavy, and expensive. The Canon EF 400mm f/4 DO IS II USM ($6,899) is smaller than your average 400mm lens, and relatively light, but it certainly isn't a budget choice. It's easy to carry all day, and its optical quality is simply impeccable. While it's pricey, it earns our Editors' Choice based on its performance. If you can live with a narrower aperture, you can opt for a zoom like the excellent Canon EF 100-400mm f4.5-5.6L IS II USM ($2,199.00 at Adorama) instead, but an f/4 lens adds some versatility, including the ability to take advantage of teleconverter lenses. Design When compared with other super telephoto primes, the EF 400mm f/4 DO ($6,899.00 at Amazon) is relatively light at just 4.6 pounds, and small at 9.2 by 5.0 inches (HD). For comparison, the EF 400mm f/2.8L IS II USM ($9,999) tips the scales at 8.5 pounds and measures 13.5 by 6.4 inches, while Cano...

The Canon EF 400mm f/4 DO IS II USM lens delivers near-perfect optical performance, and is priced accordingly.

Impeccable optics; Relatively compact and light design; Superb build quality; Rotating tripod collar; Rear filter system; Includes hard case

Very expensive

"I have only had the opportunity to use this new lens for a few trips yet but have found the quality of lens and pictures excite. I previously used a Sony A777 with a sigma 2.8 300mm, which was a older model and gave very high quality pics but I was starting to have problems with a new body and an...

Fa lavorare bene anche la 7d2 il che è tutto dire

Put simply, the Canon EF 400mm f4 DO IS II USM is an outstanding super telephoto lens. Its use of cutting edge optical technology provides superb image quality with minimal light fall-off, no noticeable distortion and very high corner to corner sharpness.

I bought this lens because I have always wanted a DO lens but the first version of the 400mm DO was a little disappointing - based on online reviews. So when the Mk II was annnounced towards the end of 2014, I eagerly waited for some positive reviews.

Light weight; Good Optical Performance; Improved IS

Could be cheaper

Weighing in at about half the weight of a 400mm f/2.8 lens, the Canon EF 400mm f/4 DO IS II USM Lens immediately finds favor with sports and wildlife photographers looking for an easily hand-holdable, high-performance lens.