[0.8 MOD] This is simply a magnificent piece of glass. Can be used as a 17mm prime lens and performs better than any other wide angle prime in the Canon lineup. Great quality, no chromatic aberration, solid build. As an architectural lens, it cannot be matched. Shooting European cathedrals and basilicas is very challenging and this lens changes the game. Top to bottom, front to back captures, both portrait and landscape. Replaced the old 24mm standby and the improvement is enormous. Pricey, both worth it.

[0.8 MOD] Exceptional wide angle tilt/shift lens is great fun in cities or other tight spaces. Image quality is exceptional unshifted, but stop down to f/11 for a full shift. Image quality ranges from outstanding wide open over most of the unshifted frame to just good at the edges of the shifted frame at f/11. Fully shifted, image quality not acceptable until f/8. Flare control is outstanding, and mechanics are excellent, and build is superior to Nikon tilt/shift lenses. This lens is unique for its outrageously wide angle view, nearly a fisheye when fully shifted. In that context, it is unequalled by any other T/S lens. Look to the 24/3.5L II for another excellent choice. Be careful with the front element!

[0.8 MOD] These two photos was taken in one frame shot - not in five frames then stitch later. It was taken around 5:30PM in Long Island NY. I am challenging myself into taking my photographs AS IS, without heavy editing in the end of the shot (only touched contrast, exposure and thats it). This lens performs well for me, and in the long run this lens will save me a lot of time editing for i can correct distortions in the field immediately. I heard there are people using this lens for portraitures and landscape and they produced amazing work. The price will compensate the use in the long run and the lens was built to last. I advise people to have external monitor for composing for the built-in camera monitor is getting smaller every year. The lens is a prime lens, a mechanical equipment manual all the time, i consider this a machine built with metal and glass - not automatic/electronic lens. This lens moves in three different directions, tilt, shift, and rotate --X, Y and Z axis, in aviation roll, pitch and yaw. The thing negative is it doesnt come with hood for protection in the field you have to be very extra-careful for the glass protrudes out of the barrel. When i go out for shoot the positive effect is the lens is so obviously protrudes and the people respect you immediately for they think you are a living legend in photography, LoL. You can actually hear people from the background say "shht move back the guy is serious look at the lens. Is that a lens?" the bleeding wallet will heal right away. The lens cap was poorly designed for an expensive lens. The lens is remarkably beautiful, engineered and well-built to last.

[0.8 MOD] This is my favorite lens for interior photography, whether I'm shooting expansive or closet-size spaces. The price is steep, but it's an investment with high yields. Using this lens cuts down on constantly having to adjust the height of the tripod. With my tripod fully extended to 72 inches I can include soaring ceilings as well as the floor. In kitchens, I can have the tripod high enough so you can't see under the unfinished underside of cabinets, yet still show lower cabinets, ovens, flooring. After using it for two years, I had it serviced, and while it was gone I realized how much I missed it. I used my 16-35, a frustrating experience that worked, but to get verticals vertical, I had way too much ceiling, so I ended up shooting almost everything at 16mm and cropping the ceiling and sides down in post to retain aspect ratio, adding unnecessary time to my workflow. I am so happy I spent the money, the results are fabulous, not only in workflow, but in beautiful photos.

[0.8 MOD] This lens defines the word sharp.

[0.8 MOD] Great lens. Clean, sharp and very wide. I thought I would miss not having auto focus but I haven't. All of the tilt / shift knobs have lots of range and are easy to control and lock. No issues.

[0.8 MOD] Great lens that requires some training. The exposure changes as you adjust the tilt/shift which takes some getting used to. The lens protrudes past the end of the housing making it very prone to damage. You can not install any filters but the results are GREAT!