VILTROX EF-M2 II 0.71x Speed Booster Adapter MFT for EF mount Lens to Micro 4/3 Cameras GH6 GH5M2 BMPCC 4K GH4 GH5 G100 G95 G85 OM-1 EM-10 EM-5

After a bit of fiddling with the lens facing glass as per online instructions, I've now got this taking some wonderful images (see above, taken at f4 on my Sigma 18-35 1.8 lens paired with a GH4). It's perhaps not quite as sharp as using a decent native lens. However I intend to use it for video, so it's more than good enough for that. It seems well made - it fits the camera/lens snuggly. Autofocus isn't perfect, but it's actually better than I thought it would be.

I’ve had this thing for ages now as I couldn’t afford the metabones version. Works perfectly, footage still looks really good. Id buy it again if I broke it for sure.

Used on a Panasonic G9 and sigma 18-35 1.8.Cons - There's slight vignetting (might be the lens) and is mitigated by stopping down to around 2.8 and initially the lens couldn't reach infinity focus, but that was easily fixed by rotating the element clockwise until it worked properly.Pros - Image quality seems nice and sharp and the extra stop of light is noticeable when compared to not using a speedbooster. IBIS, AF and aperture all work through the camera, although AF doesn't work well continuously for photos and a bit too noisy for video.Definitely worth it over metabones if you value money

I am using this on a Panasonic G7 with a Canon 50mm f1.8. It is amasing. I will recommend this without any hesitation especially for the price.. It has great build quality and ease of use

Works well sometimes but infinity focus issue is a big turn off. And the screws on the MFT mount side have all become loose and two have fallen out, making it impossible to mount to the camera without replacement screws.

I was very nervous when i clicked "order now"; I had heard good and bad stuff and therefore didn't know what to expect.I picked the right choice! The Sigma 18-35mm looks great with this on the Pocket 4K, and all things works as a native lens (just not the autofocus). When I go down to 1.2 I see some blur in the sides and middle — but if your on a budget or never go to 1.2 this is really great overall.

Mechanically the adapter is OK, but the auto-focus does not function. When I purchased, it was not clear this was an issue, although now there is a warning - but it is easy to miss on the web-site.I would like to return it but left it too late.Depending on your needs it is easier and probably more cost effective to buy a new lens.

I had a couple of older Canon lenses I wanted to use on my Panasonic G9, the Viltrox site didn't list them as compatible but they both work great, Tamron 16-300mm VC PZD and Canon 15-85mm IS USM, so I am happy and it beats the Metabones hands down for price and I would say quality too