Are Viltrox Speed Boosters Good? (Not With IBIS!)
- silverlightphotoco
- Mar 29
- 6 min read
Updated: Sep 11
INTRO:
As a budget photo & video geek, I’ve always been drawn to the idea of using a speed booster on my Micro Four Thirds cameras. The concept is to take a relatively inexpensive lens (like the Nikon AF 50mm f/1.8 D) and transform it into a 35mm f/1.2 with the help of a (.71x) speed booster. The idea is cool, but the high price tag of (some) of these adapters in the past (not saying names) has made it kind of unattainable for me. Then along came the Viltrox brand; a lower budget option that seemed like the perfect solution. I bought one, then 2 more, and I was happy...until they ruined 2 of my favorite cameras (a LUMIX GX85 and then my G85). Let's talk about what happened, and try to figure out if there is any safe ways to use these things.
BTW, this post may contain affiliate links, which means we receive a commission (at no cost to you) if you make a purchase through a link.
The Story:
WHY WE LIKE SPEED BOOSTERS
Speed boosters can significantly enhance the capabilities of Micro 4/3 cameras. For instance, the Nikon mount version allows you to use older, budget-friendly lenses while achieving a wider aperture. The Canon mount version, which I previously recommended, is pricier at around $220, but it also offers similar benefits. Unfortunately, I had to stop recommending it after experiencing electronic issues with my Canon mount speed booster, which ultimately led to problems with my Panasonic GX85.
ISSUES WITH THE CANON-MOUNT (EF-M2II)
The Canon mount Viltrox EF-M2ii speed booster/focal reducer caused significant electronic issues with my GX85. I was using an old Sigma 17-50mm f/2.8 EX lens, and the combination resulted in glitches, corrupted files, and erratic behavior with the shutter speed dial. Despite attempts to factory reset the camera, the problems persisted, leading me to conclude that the speed booster was the culprit.
ABOUT THE NIKON-MOUNT (NF-M43X)
My troubles didn’t end with the Canon mount Viltrox EF-M2ii. I initially believed that the Nikon mount Viltrox focal reducer (the NF-M43x) would be a safer bet since it has no electronic contacts. I recommended it to others, especially for those who don’t need autofocus. However, disaster struck when I dropped my Panasonic G85 while I was out shooting sports. The camera fell onto a hard surface, and upon reviewing my photos, I discovered a scratch in the upper left corner of every image. Upon inspection, I found that the scratch was on the lower right corner of the lens, which is the opposite of where it appeared in the photos.
It seems the impact of the drop caused the stabilized sensor to move, causing it to impact and scratch the sensor of my G85. My theory is that the design of the Viltrox focal reducer places the glass element closer to the sensor than any OEM Panasonic lens, which is dangerous when using it on a camera with a stabilized sensor. This experience made me wary of Viltrox speed boosters, and actually of speed boosters overall (because of the risk of damaging your camera if it's dropped).
WHAT ABOUT METABONES?
All of this brings up questions about the Metabones speed boosters (which are really good in a lot of ways) and if they could also scratch an IBIS sensor if dropped). I don't really know if they would even solve this problem (of potential damage with IBIS sensors) because ANY speed booster/focal reducer optic has an inner element that is closer to the sensor than OEM lenses...so they could potentially scratch a sensor too. There is a compatibility chart that does warn about some of these things, and I could guess and say that because the Metabones .64x works on the GX85 (per their chart) that maybe the same pattern would be true for the Viltrox, but it's a .71x (so it's not an apples to apples comparison). Plus, that Metabones is NOT recommended for the G85, so it really gets sticky and I don't really want to guess with the Viltrox and ruin my camera (as I don't want anybody else to go through what I went through...losing two of their cameras).
PERHAPS PIXCO THEN?
I tested a third brand called Pixco, which offers focal reducers at even lower prices than Viltrox. However, I’ve found that some of their products, like the Canon FD focal reducer, do not always focus to infinity (depends on the lens) let alone the fact it might have the same problem as the Viltrox (with how close the optic gets to a stabilized sensor). So, this inconsistency can be an issue for users who may not realize that certain lenses are incompatible with their adapters. It’s super essential to test each lens with each adapter to avoid disappointment.
THE AFTERMATH: A HOLE IN MY KIT
As a result of these experiences, I can no longer recommend either the Canon or Nikon mount speed boosters from Viltrox. This leaves a significant gap in my camera kit, as I relied heavily on the Viltrox 0.71 focal reducer for low-light shooting and achieving a wider aperture. Now, I’m left with a scratched G85 sensor and a GX85 with electronic issues, which is incredibly frustrating. Also, I wish I still could use the focal reducer for protection (to keep the sensor from getting dust on it every time I change lenses). Yet, that's not as much of a problem as is replacing the low-light capability of a 50mm f1 .8 that turns into a 35mm f1 .2 (with the .71x focal reducer).
LOW-LIGHT ALTERNATIVES?
With my current situation of not being able to use speed boosters on sensors with IBIS, I’m exploring alternatives to fill the low-light void. The reason is that my tests show that a number of the budget filmmaking cameras I've used need at least an f/1.4 in some low-light situations. There are a number of good f/1.4 options from Panasonic/Leica (@NigelBarros has a lot of good videos on these on both of his YouTube channels) yet due to budget, I’m considering trying some third-party 35mm f/1.4 lenses from brands like Mieke and 7artisans. My goal is to figure out a super budget-friendly camera system that can handle almost any situation, ideally with two cameras that are under $600 each. This is becoming difficult when using only Micro Four Thirds cameras, especially now that this speed booster option has been removed. The Panasonic GX85 and G85 have served me well (when using speed boosters) but without speed boosters, they really need an f/1.4 lens in low-light situations. So, I’m contemplating upgrading to models like the Panasonic G9 or GH5, which do better in low light, and are certainly becoming more affordable and maybe adding a full-frame camera.
SUMMARY:
So, while speed boosters can enhance the capabilities of Micro 4/3 cameras, my experiences have taught me to approach them with caution. The risks of damaging your camera or encountering electronic issues are significant, and I hope my story helps others make informed decisions about their gear. So, I no longer recommend either the Canon nor the (all-manual) Nikon mount version of the Viltrox speed booster. The reason is that the risk of ruining your camera (especially if you drop it) is just too great.
Here's the PODCAST that inspired this blog post.