VILTROX EF-M2II 0.71x Speed Booster, EF to Micro 4/3 Focal Reducer Booster Adapter Auto-Focus for GH6 GH5M2 BMPCC 4K GH4 GH5 G100 G95 G85 OM-1 EM-1 E-M1X E-M1 iii E-M5 iii E-M10 iv E-M10 iii

This adapter is incredible for the money. However you will need to rotate the element inside the unit to achieve proper infinity focus. I had to update the firmware for it to work with the pocket 4K. Finally, do not use this adapter past the lenses advertises t stop. For example on the sigma 18/35, this adapter stays sharp all the way to f1.8, but when you use the “boosted” range of f1.2 to f1.8, it becomes a blurry mess. This is where the metabones is better. However it is way more expensive and if you’re happy doing the infinity focus tweak as well as using it within what the lens was designed for, you’re going to be extremely happy. Perfect pairing for the pocket 4K, as dropping the money on the metabones for the pocket 4K puts you at the same price as just getting a pocket 6k anyways.

This speed booster is very useful. Sold at more or less half the price than others, it delivers the same optical quality, good communication between the adapted lens and the camera and it has a very solid construction. I use it mainly with my Sigma 17-50mm f2,8 and my Tokina 12-24mm f4, both Canon EF mount, mounted to my Olympus E-M1 mark II. With this camera they become, respectively, a 24-70mm f2 FF equivalent (the Sigma) and a 19-36mm f2,8 FF equivalent (the Tokina). Focus is still very precise, even if slightly slower than when used on their original mount. Warning: in order to achieve a perfect focus you need to calibrate the speedbooster by phisically turning the optic group. It's very simple and there are lots of videos on youtube explaining the manouver in detail. 100% reccommended.

Not had too much time to use this, just an initial exploration but is seems at first look to be pretty good. Just allowing me to use my L series Canon lens on my OM1 mkii is a huge benefit. The Canon lenses are excellent and I’m hoping to get some decent pictures with this combo. The EF 70-200mm L IS II USM worked well, I was using single point focus. Pretty fast. This combination allowed me to get to f2.0 throughout the zoom range. It worked fabulously with the EF 24-70 f2.8 L II USM through the entire zoom range and wide open (also f2.0). Focus was fast and accurate. 85mm f1.8, worked well. Little (and I mean a little) hunting for focus when wide open (f1.3) but at f16 was fine. I do have a sigma 150-600mm lens for Canon that I did try with this converter but the autofocus was slow, slow enough to make it useless for moving wildlife subjects. It did, however, allow me to shoot at f3.5 at 600mm! That’s more likely down to the lens and not the converter. While this is not perfect it’s worth 4 stars and because it has given me a means of using my canon lenses on my OM1 mkii systems camera I may up that to 5. Very pleased so far. Well worth the money.

Understand that you should update the firmware and set your infinity zoom first so you will be all good. Instructions can be found online and both can be done in 5 mins. This adapter works great with connecting my Sigma 17-50 EF to my BMPCC4K micro 4/3. I get my normal F2.8 down to an F2 and plus a wider frame. Also, keep in mind that the auto focus won’t work with this camera… but I knew that going in and won’t use it anyways. Overall, the adapter does exactly what I need and want it to do at a cheaper cost than its competitors.

I tried this adapter with multiple cameras and lenses and each time the camera reads F- and autofocus doesn't work. I tried to update the adapter's firmware, but the drive came up completely empty, no firmware appeared to be installed in the first place. Following the online instructions for updating, I tried dragging the update files onto the adapter drive anyway. When I did, the adapter would not eject. When I unplugged and plugged back in, the drive was completely empty again. Also, the latch that locks the lens onto the adapter doesn't work. It's build so cheaply and it doesn't line up, so you can unscrew the lens without pressing the lever to unlock. Total piece of junk. I returned it and can't believe I paid over $200 what amounts to a junky passive adapter.

I purchased this to mount my Canon EF lenses to my LUMIX G7. So far I’m pretty happy with it. The build quality is pretty much all metal and seems solid. Autofocus, aperture control & EXIF all work fine. Autofocus is a bit sluggish, but that’s to be expected when adapting non-native glass to any system and not that big of a deal for stills. Definitely a great and cheaper alternative to Metabones. Image quality is good and fairly sharp at about f/2 and up, anything lower gets soft but they’re still reasonably exceptable. It mounts great to the G7 snuggly and lenses mount nicely too with out any issues.

Having had many Viltrox products over the years, I ordered this EF-M2II when I needed something to adapt my Canon lenses to my Micro Four-Thirds cameras. This did not disappoint. I've used it with both Canon and Sigma lenses without any issues. The AF seems quick enough and I am not seeing much if any loss in quality (just the usual you normally get with lens adapters). Again, Viltroz comes through with another great adapter!

When it works, it’s great. I moved from Canon to an OM-1 MkII but I hated to give up my favorite Canon macro lens, the 180mm f/3.5L. I bought this in hope that I could still use it on my new camera, as it was on the list of compatible lenses. I was able to get a couple of shots off before my camera screen went black. I kept having to turn the camera on and off in order to make it work, and sometimes multiple times. Definitely not conducive to an enjoyable shooting experience so I returned it. Side note: I ended up buying a full-frame Canon RP and an EF to R lens adapter which was cheaper than buying an Olympus macro lens!

This really works and I have no idea how Metabones can be even better. Best benefit for the price. It worked neatly with my Sigma 18-25mm.

Panasonic GH6にEF－Sレンズを使用する為に購入しました。 まず同様の商品を複数所持していますが、正常に動作するものはごく僅かです。 この商品もズームを操作したとたん認識が外れることがあります、接触が悪いことが無ければ基本動作は可能であろうと思います。 AF-Sにおいては基本的には問題なく、一部の暗いズームレンズでフォーカスがズレる現象が見られました。 AF-Cは動作しようとするのですが動作しないようです。 F値はいい加減な表示をします、ファインダーと仕上がりが違うことがあります。

quick reliable and great value

It does what it basically describes; using it on an em1x and there are some times that it disconnects or loses connection, so you have to make sure it is securely connected to the camera, or undo and reattach the lens repeatedly. Very slow for focus, but effective in that I'm able to use my Canon lenses on the Olympus body. Just don't count on speed!

一度目の購入：OM-1のカメラ本体には装着できるが、EFレンズが装着できない。アダプターの赤点にレンズ赤点を合わせ右に回すが、少し行くと止まってしまう。何度やっても同様。別のEFレンズでもトライしたが、同様。初期不良と判断し、返却して返金となった。 二度目購入：一台目が初期不良と判断したが、どうしても使用したいと思い二度目の購入。しかし状況は同様。一度だけ本当に無理やり回し何とかカチッとなった（装着できた）。AFも絞りも正常に働いた。…が、やはり装着のこの固さは尋常ではない。もう一度装着しなおしてみたが、レンズフードが壊れてしまうのでは？というほど力を入れてようやく装着できた。レンズ交換ができる一眼が野外でこれではとても使えない。この仕様なんだろうと判断し、二度目の返却となった。 実はこのVILTROX社のストロボ（以前のもの）がとても気に入っていて、７台リピート買いしていたもので、この商品には期待していた。残念だった。しっかり装着ができれば、もっと試撮したかったが、そこまで行くことができなかった。