I read this comprehensive review before purchase and you should too:http://www.imaging-resource.com/PRODS/canon-eos-m/canon-eos-mA.HTMI'm an amatuer photog for more than 40 years. Until recently, my only concession to digital photography was the purchase of inexpensive Canon point-n-shoots. As film photography has become a greater burden and digital has caught up in terms of quality while surpassing in convenience and affordability, my discovery of this little gem at a bargain price was perfect timing. Adding a $15 adapter, I can use may ancient but excellent FD mount Canon lenses - think F1 and AE-1 cameras. Auto-focus speed doesn't matter to me because I still prefer to manually set almost everything. That said, the AF performance of the EOS M seems equivalent to that of my son's Nikon 1.My purchases for my entry into serious digital photography to date include: the EOS M with Speedlite 90EX and EOS M 18-55mm IS lense: an SD card (PNY 64 GB High Speed SDXC Class 10): a spare battery (Opteka LP-E12 LPE12 2000mAh Battery Pack): a lense adapter (Fotasy Canon FD Lens to EOS M Lens); and a neck strap (OP/TECH USA System Connector Super Pro A).

If you want to use your old FD lenses, this is one of the best choices. All you need is an adapter ring "Fotasy Canon FD FL Lens to Canon EOS M". The pictures turn out great, you just have to get used to the manual adjustment but there is an automatic ISO adjustment to help, if you want.

What can I say! It's a Canon body cap that will fit any canon camera with EF anf EF-S mount, doesn't matter if it's a full frame, APS-C, or film. In other words, if your camera was made in the last 30 years, this cap will fit!

If I were to choose one lens for my Canon M series this would be it. Fast and with a very versatile focal length for walk around photography. Excellent for travel photography, very small compact and lightweight.

This is easily one of the best lenses Canon has ever made for their Mirrorless system. Highly Recommend if you want this focal length.

Works great to attach my Canon DSLR to my Celestron model#94175 reducer/corrector

I purchased a Canon FD to Leica M adapter in order to get some more use out of my 17mm Canon lens. I’m pretty impressed with it so far. It seems considerably better quality than the cheap imported adapters, and not as expensive as a Novoflex. The lens hooks up solid and it feels solid on the camera body. I will most likely try some of their other adapters as necessary.

The walkaround lens. This very topic leads to a heated discussion among DSLR photographers.First, determine your budget, focal length, and aperture needs.If you frequently find yourself zooming out to get everything in a frame, you will want a wide angle lens such as this. If you frequently find yourself zooming in, this is not the lens for you. On a full frame body such as Canon EOS 5D, this lens becomes ULTRA wide angle. On an APS-C crop body such as Digital Rebel XTi (which I used for this review), it becomes MEDIUM wide angle. But thanks to 1.6x crop factor, this lens expands to more usable 35mm equivalent focal length of 27 to 64mm.Second, audition the lens if you can.By definition, a walkaround lens should be relatively portable. At 1.1 lbs., Canon's EF 17-40mm f/4L USM is neither super light nor neck breakingly heavy. In fact, it weighs almost the same as Digital Rebel XTi -- really nice balance. The lens feels very solid with supreme build quality that only L-series lenses offer. Although this lens is weather proof and therefore sealed against liquid and dust, I strongly recommend getting a 77mm filter to protect the front lens element. With it, this lens is made to last.In terms of looks and feel, it doesn't get much better. Its rubberized full-time inner focus manual ring USM focuses smoothly, quietly, and quickly. Since it's inner focus, the lens will not extend beyond its metal casing whether you zoom in or out. The focus window shows focusing distance from 0.28 meter (0.92 feet) to infinity. The focal length marker indicates 17, 20, 24, 28, 35, and 40mm. The lens exudes quality from tip to tip.You may tolerate heavier lens or may not mind lesser build quality of cheaper lenses. A walkaround lens will be used very often, so make sure you will be comfortable with it.This lens is famous for saturated color and deep contrast. Its images are simply stunning. At 17mm wide angle, barrel distortion is noticeable but relatively mild. From 24mm to 40mm, its images are distortion free and perfectly suited at capturing people.Vignetting (corner darkness) is minimal with mild chroma abberrations (color shadows). At f/4 aperture, details become noticeably softer toward the edges. The center region is very sharp and at f/5.6, edges remain fairy sharp. Thanks to 7 diaphragm blades, this lens can produce very nice bokeh at 40mm (blur effects).One of the most cited weaknesses is the f/4 aperture. In my experience, a bump in the ISO speed and steady hands are all you need to take well focused images indoor. On the other hand, if you are shooting with very little amount of light, you might wish for f/2.8 or image stabilizer. Although the difference between f/4 and f/2.8 is just 1 stop, my other lens, Canon EF 24-70mm f/2.8L USM (too heavy to be my walkaround lens) easily outperforms in such challenging situations. But by and large, I was not handicapped by the f/4 aperture.Some of the main competitions (sorted by price):- Sigma AF 17-70mm f/2.8-4.5 DC macro: Good zoom range with macro, and generally solid performance if you can get a good sample. It does suffer from a bit slow focus mechanism, soft corner, and chroma aberrations. Works only with EF-S mount.- Sigma 18-50mm f/2.8 EX DC: Very good value for f/2.8 aperture, but Tamron's 17-50mm is a bit better lens overall. Works only with EF-S mount.- Canon EF-S 17-85mm f/4-5.6 IS USM: This "traveler's lens" has a wider focal range than most wide angle lenses (widest among Canon) and is equipped with an image stabilizer. While it is a Jack of many trades, it is the master of none. Every lenses on this list will perform better at particular focal length. Then again, none of the lenses on this list has as wide focal range. It is famous for extreme barrel distortion at 17mm and chroma aberrations. Works only with EF-S mount.- Tamron SP AF 17-50mm f/2.8 Di II LD Aspherical (IF): This is the most direct competitor. It takes sharper images with faster aperture while costing less. Both the build and focus mechanism are significantly worse, but should be good enough for many. Works only with EF-S mount.- Canon EF-S 17-55mm f/2.8 IS USM: This is THE reference, if you can afford it. Its images have razor sharp details and great performance all around (minus vignetting, which is typical of EF-S lenses). The build quality is worse than L-series but still pretty good. Works only with EF-S mount. This is the best EF-S lens hands down.- Canon EF 16-35mm f/2.8L USM: One of the most expensive wide angle zoom lenses. It's larger and heavier, but has f/2.8 aperture.This is how Canon EF 17-40mm f/4 USM stacks up.Pros:- Among the very best build quality.- Excellent, buttery smooth, super fast front-focus system.- Top notch color and contrast. Very sharp center resolution.- Almost non-existent vignetting, generally low distortion, and well controlled chroma abberrations.- Ideal weight and size for walkaround purposeCons:- Edge softness at f/4 aperture.- Narrower focal length than most competing lenses.- Slower than some third party lenses.All in all, this is an excellent wide angle walkaround lens. It may not offer the most bang for the buck, but if you value full frame compatibility (EF lens mount) and excellent build quality, this is the default choice. This lens comes with a nice pouch and a lens hood. I find the hood to be somewhat ridiculously shaped and because the lens is resistant to flare, I do not use it often when shooting outdoor.