I mostly shoot landscapes and used the Canon 17-40mm f/4L USM lens till now. Just switched to the Canon EF 16-35mm f/4L IS USM Lens and have been amazed by how sharp the images are especially the corners at either end of the zoom spectrum. Its a lightweight wide angle zoom with superb construction quality. I am sure it will provide me many years of service similar to the 17-40mm lens which I am now inclined to sell.

I don't want to bore you with all the technical aspects of this lens. There are enough of them online. I bought the lens for landscape and part-time street photography and image resolution is incredible. It's sharp to all corners from its low focal length to its max. I walked around town with my 5D Mark iii and my shoulder thanked me. Feels as if it was made for Mark iii or any other DSLR. The usual Canon quality applies. Yes, it's plastic but its 'good' plastic with a solid feel. Zoom and manual focus is smooth. I'd actually like some more resistance but it's not a deal breaker. Auto focus is the quickest I've experienced: see it, shoot it. Very quiet too. I thought I'd miss the wide open aperture but I really don't with this lens. You're not going to get the glorious bokeh of the 50,85, or even the 135 but you get a pleasant out of focus blur. Bear in mind, this lens wasn't meant for that but you'll be pleasantly surprised. IS? Nice feature but I've never had IS at this focal length in my other lens and I can't tell if it's any different. It was between this and it's 2.8 older brother and after seeing the MFT charts and taking my own pics, I'm glad I bought it and you'll be too.

I am very glad I purchased this lens. I was initially going to purchase the 17-40 f/4L wide angle lens by canon but read a lot of reviews stating that this lens was better than both the cheaper 17-40 and the much more expensive 16-35 f/2.8L. I am very glad that I spent the extra $ to get a very sharp lens, no issues with darkening. Wide angle distortion is minimal and expected with this type of lens. I would buy again. This lens was slightly heavier than I expected (it is heavier than my 24-105mm f/4L) but the weight feels appropriate attached to my Canon 6D, it's not too heavy. Someone who uses the stock neck strap with this lens may have a sore neck/shoulders by the end of the day. I did buy a B+W UV filter to protect the front element and to finish the weatherproofing.

This was my first piece of L series glass, all I can say is WOW! Why did I wait so long to upgrade. I always thought I was doing pretty good with my kit lenses until I put this on the camera. Been shooting with this for a little over 2 months now and I am very pleased with the purchase. I can't wait to buy my next one, as I upgrade my lenses prior to upgrading my camera. I am using this on a T2i, can't wait to use it on a full frame to take advantage of the wider angle.

I rented this before buying (lensrentals com) and really enjoyed it, so I have bought it with no regrets. It's going to be on my 5D Mk III very often, and may become my 'walkabout' lens (although I'll keep my EF 24-70mm f/2.8L II close at hand). Great lens! And the difference between 24mm (short end of my 24-70) and 16mm (short end of this lens) is very dramatic. Love it!

I don't shoot video at all, so it's all about photography for me. I love this lens, it's sharp from f/4 at all zoom range, little to no vignette at all zoom range, easily controllable barrel distortion from camera (my 6D has the ability to fix it in camera for jpeg files) or by post processing software. The IQ is awesome, just awesome. The IS is amazing, allowed me to take handheld photos in very low light conditions, and I've never thought they would be sharp, but IS is phenomenal! The build quality is newer-standard L lens by all means, creamy smooth and very wide rubber focus ring (grip is awesome with/without gloves), tough and resisting zoom ring - which is good IMHO to avoid creeping or any change even walking with the lens. Weather sealing tested several times with b&w clear protective filter attached, tough, rugged, took it with me on rainy/windy days and did not afraid to use it under any conditions. I love the whole focal length of this lens, there is no length it's bad at. From 16 to 35 this is an awesome sharp lens. The bokeh is quite good, I don't usually like bokeh for these focal length values, but when I do get a bokeh shot - it's really nice. Cons: F/4. This is not a good night photography lens by any means. It's capable to take some low light street/in doors whatever photos, but F4 is just not enough to get some good stars action, by boosting the last stop by shutter you risk at blur, by boosting ISO you risking unusable noisy images. BUT! IMHO, Instead of getting the 16-35F/2.8, just get this lens and with the change get the rokinon 14F/2.8 for night sky photography, because besides the fact that 16-35F/4 lens is super sharp, I love that this lens is 77mm thread, which allows you to share filters/filter holders between rest of your 77mm lenses, and I love the fact that 77mm filters usually costs less then 82mm.

An excellent choice if you're looking for a sharp, rugged wide angle lens. I bought it to use for landscapes on my 6D and couldn't be happier.Check out the photos below my first time out with the lens.

With a passion to shoot architecture and landscape photography a wide angle lens is a must. This Canon 16-35mm IS F4L doesn't dissapoint. The sharpness from this lens is wonderful, it is useable wide open at f4 and improvements are hard to recognise as you move up to f5.6, f8, f11 etc. It really is a sharp lens and the resolving detail is just amazing - the fine details are really well defined. The build quality is great with high quality materials used and the IS is a wonderful addition to be able to handhold shots in low light etc. Very fast to focus and quite too. Would highly recommend this lens for architecture and landscape photography.

I had read that this lens was superior to the f/2.8 version, and it is!! It is a true wide angle zoom on full frame and on APS-C it provides about 25-56mm.

I have used dozens of lenses in Canon's lineup and own my fair share of L series glass and EF USM lenses, but this lens has earned its place in my bag, and is my second favorite lens behind the Canon 135L f/2. Of course, these two lenses are completely different, but they both get the job done. I would go as far as to say that this lens gives the sensor the full capabilities of dynamic range that it can handle and maintains contrast and colors better than any lens that I have seen in Canon's lineup. Additionally, it is sharp throughout the entire frame and not just at the center like the 16-35 f2.8 and the 17-40 f/4. IF you are into landscapes, real estate, or artistic portraits, then this lens should be a serious consideration for your purchase. As always, B and H was flawless in their execution of my purchase.