Good idea and concept, but its hard to judge this product when using it on the EOS-M with its horrible focus. You don't really lose any stops with you EF lenses. The IS does not seem to transfer over. The EF lenses do what they are told, but a continuous auto focus and generally undeveloped Hybrid APS-C sensor is not fluently compatible with the current EF-s and EF lenses. Video is horrible with the CON AF on. It.'s just not pretty. If you have EF L lenses, already have a dependable DSLR, and you love the EOS-m with cash burning in your pocket, I would say get it. If not, buy the other EF-M lens you dont have or the one coming out soon.You will be disappointed if you buy this and a EOS-M in one shot. Product is fine, the root problem is the M.

I purchased this adapter along with the EOS M camera kit to use with my EF and EF-S lenses. After less than a week, I have been able to try out with the EF 50mm F1.4, EF 70-300mm L, EF-S 17-85mm, and EF-S 60mm lenses. The adapter fits perfectly. Same form and fit as the Canon extenders I have. The EOS M is of course made very tiny with any large EF lens. It creates a sort of 'pocket Rebel'. Of course, once you mate with the larger lens, this is no longer going to fit in anything less than a massive coat pocket. The combination of camera, adapter, and lens seems comfortable after brief handling. The EF 50mm was a very comfortable combination, the adapter does not add a very large amount to the overall combination. The upside to this adapter is if you already have a variety of EF and/or EF-S lenses. The image quality of the JPEGs, right out of the camera ranged from expected to stunning (the latter results obtainable with off camera studio flash strobe and soft box). The adapter was immediately a huge part of the EOS M camera purchase. I highly recommend it if you have other lenses. Again, the results I got with the EF-S 60mm macro (and studio lighting) were stunning. It transformed the camera from curiosity to studio prime. No problem using manual mode and Pocket Wizard. Include this adapter in your purchase and you won't be looking back.

I love this lens. It's compact, the optics are good as with the other EOS M lenses, it focuses fast. If I had one thing to pick on it would be the lens lock which is also present on the EF-M 15-45. I'm getting used to it but otherwise it's a fun lens and rounds out the EOS M3 kit.

Not much to say here, this device allows you to mount an EF lens onto your EOS-M camera, and appears to be well built. Done.

This is a very good entry level camera, but lacks some advanced features expected with a pro camera.Please be aware:- Kit does not include a memory card, so the camera is inoperable out of the box.- Mount Adapter EF-EOS M (~$200) is required to use Canon EF and EF-S lenses.

I have a Canon EF to EOS R adapter for an EOS RP camera and I bought this adapter to reduce the swapping. From what I can see it works as well as the Canon one. I tested it on a 17-40 F4L and on a Sigma 100-400 5-6.3 C and I saw no difference. So I'm very happy with it.

Adapter works great, it lets me attach my EF and EF-S lenses to my Canon EOS M without any issues.

I own an original EOS-M, no networking capability. It came with the two EF-M lenses that were available at the time, and I also acquired an adapter ring to fit original EOS-EF lenses to the camera so I could use my other 300mm len. Now, a 300mm EF and EF-S vs 200mm EF-M is a fair approximate comparison IMHO since digital cameras and lenses have a different focal length, so don't think I stacked the deck or anything. This lens is lighter, smaller, and integrates better with the system. The zoom is smoother, and the range of the camera is finally what I expect it to be.As for the seller, well, they said this was a used lens and had a few markings, but I couldn't see anything without magnification. Full Points for Full Disclosure, guys