K&F ConceptM42 to NEX Lens Mount Adapter, for M42 Screw Mount Lens and Compatible with Sony Alpha E-Mount Cameras

I haven't tried any other model but this does the job well at a fair price.Easy to connect, feels sturdy, looks good, came in a nice box.Photo taken with a worn Minolta MD Rokkor 50mm 1.4 on a A7RIII.Edit -- it does leak a bit of light (test with a 30 sec exposure with front cap on) but to me this gives a very interesting effect - see photo, it doesn't spoil the image but gives it a luminous effect, like the light is bleeding out of the photo.Please note: Their updated model, with the copper ring matching that of the camera doesn't leak light (same test). Keep this in mind if you don't like that, as it's only a few pounds more. (I have tested that updated model on a M42 model as well, no light leak.

The quality of these adapters are unreal. This will be my second m42 adapter from K&F and both are exceptional quality, and accommodate the small aperture pin on these lenses.My only feedback would be ideally if the adapters were a bit lighter, especially as m42 lenses themself tend to be on the heavier side so the weight does become a little much but not enough for me to not use them by any means.

Good quality item, fit perfectly

I had previously purchased several Canon EF lenses for my old and heavy EOS 5D mark ii. Having sold the 5D a decided to take a gamble and buy this converter. All my Canon lenses can now be attached to the Sony and the results are extremely good. Auto focus is fast, though it can struggle a little in low contrast situations. In such a situation it is easy to set to Manual focus. I've tested the following Canon lenses with great success.EF 100mm f/2.8 macroEF 50mm f/1.8 a cheap lens but really sharp resultsEF 28-105mm f/3.5-4.5EF 17-40mm f/4 L seriesEF 24-105mm f/4 L seriesCanon Extension Tube EF25 ii works too!The only other slight negative is that the lens image stabilizer doesn't seem to work on those lenses that have it.The other advantage is that there are lots of Canon lenses available in the second hand market. Why buy a new Sony lens when you can get good second hand Canon ones!The picture was taken using the Canon 100mm macro lens hand held.

Having just swapped over to Sony from Canon, after many years of being loyal to Canon and having many of their lenses, I ended up with a few of their cheaper lenses that simply weren't really worth selling as the shipping and hassle would've been more than what the lenses are worth.So I decided to put the lenses to good use with my new A7 III, but I first needed an adapter. Enter this adapter. It's incredible!Sure, it only allows for manual focus, even though my Canon lenses are AF, but who cares? This adapter has allowed me to get back to basics with my camera and enjoy photography, almost at grassroots level. It's so refreshing, especially with photography being my main business.The adapter is built like a tank, and together with its box, it fits comfortably into my camera bag. I don't go anywhere without it.K&F have knocked this one out of the park! If you're in the market for an EF/EF-S to E adapter, this is the one you want!

K&F market themselves as decent quality but then don't have someone check if a lens even fits on the mount before it leaves the factory. I had the same non-fitting problem with one of their PK to NEX adapters and another of theirs leaked light. Fortunately with free returns its not such a big problem but a waste of money and reputation for K&F, i've ordered another in the hope the next one works, if it doesn't i'll never bother trying K&F again. Get your act together K&F - UPDATE: received the second one and it also doesn't allow a lens to be fitted.

The adaptor itself seems to work fine. I've used it with lenses like the Helios 44M 58mm and Helios 28mm wide-angle with much success. However after shooting with it for several days, I've noticed maybe a dozen fine metal particles covering my A7ii's sensor. I can't be certain whether the particles came from a lens or the adaptor itself, but it might be a good idea to leave one of these adaptors on each M42 lens you have, or purchase a more expensive one that won't wear.

Firstly, I have over 100 vintage lenses, so I've tried so many different adapters and this was the first K&F adapter that I bought in 2015 (I'm going through my old purchases to leave long-term reviews). Since then I've bought quite a few more K&F adapters for my other mount lenses, so at this point, you might be able to guess that I like these adapters a lot!So why do I like them so much? They are not the cheapest adapters out there, but for the price, they are the best adapters I've tried so far. They fit onto the camera quite snuggly which is obviously a good thing and the same can be said for the lens side on the adapter. Overall build quality is very good, even better than I would expect at this price point, so I highly recommend these to anyone using vitnage lenses on modern cameras!