Canon EF 17-40mm f/4L USM Ultra Wide Angle Zoom Lens for SLR Cameras

First of all, let me start to talk about the delivery/amazon.com service for this purchase of mine.About the delivery/service: (skip this part if you are only interest in the lens review :) )Usually I am very content with amazon's service. They respond fast and if something goes wrong, they compensate one.Unfortunately this time, things weren't as great. And to be honest I was just disappointed of the service.I have an Amazon-Prime account and therefore 2days delivery was 'guaranteed' (cite) since I have purchased this item from amazon. If it was not amazon prime and if it was just delayed for a day, I wouldn't bother mentioning it. Yet this time, the delivery was all confusing. I received daily messages that the item was out for delivery and a couple hours later that the item has to be sent back because of a wrong location. The lens ended up coming late about one week. All wouldn't be as but if I didn't have work to do and a travel for the weekend, for which I both bought this lens for. It is not the fact that it came late which disappoints me so much, it was the fact that amazon guaranteedtwo day shipping and as they were usually reliable, I sold my other lens, expecting this one to come on time (It should have come on Wednesday, so I did calculate a possible two day delay...). It is moreover the opportunity costs I had to pay because I did not have a lens in this range neither for work, nor for my journey.Amazon did offer me some kind of compensation on the first day of delay, a $15 certificate for the next purchase from amazon.com. To be honest with you, this was not worth even a tiny bit of what I missed due to the delay. And until now, I haven't received any information about the further process yet. In this case they should have kept better contact with their delivery/supply chain.Now we come to the hot part :DAs you can see I still gave the lens 5 stars, because the lens itself is a great piece of glass. I got the lens while it was still on a very good deal!I just got my copy of this lens today and tried it out right away and I am already happy with this lens! And as you can see I wasn't able to wait to share my excitement (which was quite dampened by the delay though)Just look at the pictures which were uploaded. This thing is just great!1) Overall first impression and optical quality:I am currently using a Canon 7D. My other lenses are: Canon 70-200mm f/4 L, Canon 50mm f/1.8 and Rokinon 8mm f/3.5 fisheye.The Canon 17-40mm f/4 L just completes my kit.I haven't had the opportunity to fully tet the lens yet. What I can say is that in good to decent light conditioning this lens is performing at its best! The details, the saturation and the contrast are great with this lens. Moreover you can get really really close to the object. I have the feeling that you could use this one even as a macro lens. I might be one of the lucky person who got a very good copy of this lens, but I am very pleased with Canon so far and think, that their Quality control is really good.And yes - this thing is BOKEHLICOUS :) Nice, smooth Bokeh!2) The build qualityThose who had the pleasure to use L lenses before can tell that the build quality and ergonomic of these or second to none.And the 17-40mm f/4 L is no exception. In fact, this lens is one of the lightest Canon L lenses. But lighter does not mean cheaper. In opposite! The build quality is great. A very sturdy piece of glass, good weight to carry it around all day, attached to a big camera such as the 7D or 5D MarkII without getting tired.One also has to mention that this lens is weather sealed. IMPORTANT NOTICE: The weather sealing is only complete when you mount a 77mm UV Filter onto it (I decided to buy Hoya . very good quality, reasonable price. No flare at all.)3) The priceThis is in fact of the most affordable lenses by Canon. And yes, call it: BANG FOR THE BUCK. Of course, everything has to be regarded in relative terms. Whoever can really call around $700 to be cheap probably doesn't have quite a tight wallet as most of us.But in terms of L lenses, yes, this one is one of the most inexpensive glasses you can get. And don't be fooled by the price, this has nothing to do with the quality!4) What's great about it?a) It is an L lensb) Resale price does not drop significantly over timec) comes with leather lens-bag and hood (for ASP-C DSLRs one has to be another hood though, since this is actually a FF lens)4) looks sexy because of the red ring ;)5) Compatible with FF DLSRs (for the future)!And lastly, yes this lens does not have IS. But at this wide angle one usually does not need one.And yes, this lens only has an aperture of f4. But as always, ask yourself what you really need and if you really need the extra stop to f2.8 which costs you almost $1000 more. For me, this lens is all fine. Shooting in really poor light conditions might be a little tough, but that's when you should use a flash and/or a monopod/tripod. But even handheld I did not have a huge problem with this lens, most of all because of the ability of the newer cameras such as the Canon 7D to perform quite well in low light in terms of dealing with high ISO.An update will be coming soon, which will include more about the performance in normal and also in low light!

If you're shooting an APS-C Canon and you've decided that you only want EF full-frame lenses for future use on a full frame camera, the 17-40 is a must-have. The focal range on the cropped sensor is 27 to 64mm which covers a large range for the majority of shots most people are likely to take. I've found this lens is perfect for social gatherings and essential for group shots. The size and weight is perfect on the 7D, making this my favorite lens for handling (compared to the 24-70 f2.8L and the 70-200 f4L). The build quality is superb. The focus and zoom rings couldn't be smoother and AF is fast. While this is a sealed lens, I hear that it's not fully sealed until a filter is fitted. With one in place, the zoom extension is completely internal, so there's no change in length when zooming from wide to the long end.This lens is a fixed f4. If you buy the lens with the understanding it is not an f2.8 and will not get you the lower ISO and/or faster shutter speed of an f2.8, the lens does very well in most shooting situations. On the 7D it's even better with the excellent high-ISO performance of that camera (I can shoot at ISO 3200 to 5000 without much concern). While it is reasonably sharp at f4 across the focal range, it is not as sharp as when stopped down to f5.6. Also, boarder sharpness falls-off a bit wide open and close to 40mm. However, these are not big issues. Contrast and color with this lens is excellent. My only caution from experience is to be careful when adjusting the point-of-focus to depth-of-field balance with the micro AF adjust on the camera (if you have that feature). What may appear to be a correct adjustment with a focus scale sheet that uses the center of the field, may end up causing excessive edge softness of your images due to the edge of the frame starting to fall out of the depth of field. I believe this may be due to the field curvature characteristic of a wide angle lens where the focal plane is not equidistant from the camera lens but slightly curved. I spent some time setting the correct AF micro adjustment by photographing a large bulletin board with very small lettering and symbols across both dimensions while making sure the camera was pointed square to the center so that all corners were equal distance from the camera. Once you have this dialed-in, you can test the center-to-corner sharpness of your lens at different focal lengths and apertures and determine whether you may have any sharpness issues with your copy. Initially I thought I had a bad lens copy that was soft and de-centered, but after getting this procedure right, the lens proved to be sharp.While there are other excellent options such as the Canon 17-55 EF-S f2.8 lens, this one is full-frame compatible, it's weather sealed, it has superior build quality, it's an L lens with that unmistakable red ring at the end, and it's the next greatest lens bargain second to the 70-200 f4L. While the hood may look odd, remember that it was intended for a full-frame camera where this lens would be a true 17-40mm - making a shallow hood necessary.

Use this on my Canon camera for wide angle shots and found this L series lens to be up to par with the other L series lenses i use. I’m not a professional photographer but I’ve found this lens helps me get highly detailed photos that coulnd’t be captured with cheaper lenses i first tried out.