Viltrox EF-EOS M2 – Speedbooster x0.71 for EF Lenses on EOS M with AF

Jun 12, 2018
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#1
Hi, i got this new Speedbooster yesterday from eBay for €145.-. I didn't had the time to do some real photos with it but from my short testing it seems that AF is much slower with this booster and you need more light, despite the fact that it increases the amount of light hitting the sensor. It also converts the lens parameters correctly so my EF 28/1.8 is shown as a 19/1.2. Both mounts and the barrel are made of metal and it feels very sturdy. It also has a removeable tripod mount and it comes in a transport case that's a bit bulky. It's a bit shorter than a "dumb" EF on EOS M converter but much more heavy. There is also a USB port for firmware updates.

I hope i will find some time to shoot with it over the weekend and post some pictures. I wouldn't be surprised if its not very sharp in the corners but, most likely it will be used for photos with the corners out of focus anyways. For me it's also more a gadget to find out whether a FF camera is interesting to me as my EF lenses will behave almost as mounted on a FF camera.

B.
 

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Jun 12, 2018
29
20
#3
Hi, weather is crap today but you all know the feeling when new stuff is in the house and you have to do something with it. So i did some really amateur testshots to get a glimpse of how this speedbooster is doing. All tests are done with the 28/1.8 which is not a stellar performer even without further optical elements but it's the only EF lense i have that has a short FL and can be used for a test like this from my balcony.

Magnification
I put the camera on i tripod and did the shot with speedbooster and with regular adapter. It's not realy focus to infinity but more than 10 meter. Then i tried to match both pictures in Photoshop. As you can see i moved the camera between the shots :) Scaling is 70.5% so the x0.71 is confirmed. I used manual exposure set to 1.2/1.8 and 1/2000 / 1/1000. The shot with regular adapter seems a bit darker so i guess the boost is even a little more than one stop.

Sharpness
This time the fence on my balcony. I tried to place the camera at right angle to the fence but not scientifically. It was only about 70cm away from the camera and matching both images resulted in a little less than 70% and again a little darker. As you can see the 28/1.8 isn't exactly sharp in the corners even without booster and even on a crop camera. But there is enough usable area in the center of the image even with booster. The CAs are easily removed in LR.

Separation
The prime reason for me to go FF would be to have more focus separation. I used a globe to simulate a portrait and tried to frame it the same size with all focal lenght. I invited the EF-M 22/2.0 to the party as it's very close to the 28mm with SB.

Autofocus
Can't really tell right now. But it's definitely worse with the SB. I must shoot some real photos to come to a conclusion but i think if you don't plan to shoot sports&action it should work.

to be continued..

B.
 

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4fun

picture? perfect!
Nov 19, 2018
181
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#6
@Bambel: if you have any EF lens with STM AF-drive - e.g. EF 40/2.8 STM or EF 50/1.8 STM or one with Nano-USM (70-300 IS Mk. II) ... maybe you could try and see whether they focus faster? EF 28/1.8 is not exactly a stellar AF performer even natively on EF bodies and much less so in live view/mirrorfree operation.
 
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Jun 12, 2018
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#7
I received a EF 50/1.8 STM today :) My old EF 50/1.8 II (A.K.A. the coffee mill) didn't work on the M10 even with the regular adapter (and this lens is understandably missing on Canons compatibility list for the EF-M adapter). I only played around for a few minutes and the STM seems to work well but AF is a bit slower with the booster. I will visit a christmas market over the weekend and hope to shoot some photos there.

B.
 
Likes: 4fun
Jun 12, 2018
29
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#9
So i'm back from my trip and here are my experiences: I only had the 50/1.8 STM on the SB with me and TBH i wish i had at least taken the regular adapter with me. AF with the SB is a bit challenging. In bright daylight it works quite well but in low light my M10 had problems getting in focus. Sometimes it just hunted and sometimes i got a lock but the image was completely out of focus. On the other hand the optical quality seems to be very good. All in all i like the SB but you have to know it's limitations, especially in low light or when you try to shoot subjects in motion.

BTW i like the 50/1.8 STM. AFAIK it has the same optical formula like the 50/1.8 II but the overall build quality and how it looks is a world apart from it's predecessor. In fact, while i never had an issue with the II, i used it very seldom because i didn't like the poor build quality. I'm sure i will use the STM much more often. I also never liked this FL on a crop sensor but with the SB it's so much more usefull.

I will buy an M50 in the next few weeks, i try to wait for some killer christmas deal. I hope that the DP sensor in the M50 will provide better AF than the rather vintage hybrid AF on the M10. Nevertheless, i will keep the SB as i didn't had such fast primes on crop before. But again, it's not realy a "drop in" solution that works without noticing it, but maybe some firmware updates will improve it's performance.

The attached pics are shot mainly at 1.2 - 1.6 as it was very dim lit.

B.
 

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Likes: 4fun
Jun 12, 2018
29
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#10
Next update..

Firmware
Viltrox is working hard on firmware updates, the latest version is 1.4. They fixed a few bugs and improved a few things. If you turn off the camera the focus barrel is now retracted and there was a bug on the M50 that the FL and apperture was not correctly convertedon the first shot. Also, the lens name is now in the EXIFs.

Autofocus on M50
I bought an M50 the other day and AF works much better on this one. Only in very dim light it still strugles a bit but otherwise it's very good compared to my M10. (BTW: i love the M50. This cute little thingy is a real camera but very very small. The small grip is so much better than on the M10, even the 17-55/2.8 is at least usable while not comfortable off course. My 7D will now be relegated to the heavy stuff ;))

The pictures are taken with the 50/1.8 STM and the 100/2 USM. All at 1.2/1.4 and no corrections in LR.

B.
 

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