Viltrox EFL Pro adapter

I bought the Viltrox mount adapter EF-L Pro new from BH photo/video last month and when I use it with my Canon EF 85mm f1.8 lens, I can not get a wider aperture than f2.0. This lens works at f1.8 on my canon cameras, and a Canon EF 50mm f1.8 works at f1.8 with my L mount camera and the Vlitrox EF to L pro adapter.

Also my EF 50mm f 1.4 lens shows f 1.45 on the CCFF as the widest aperture.

My L mount camera is the Black Magic Cinema Camera 6K Full Frame.

Ideas why this isn't working correctly? Having the widest aperture the lens is capable of is very important to me.

Thanks in advance for your help.

First step in such kind of case from my expirience - trying to update the adpter's firmware. https://viltrox.com/pages/downloads-adapter
Second step - try to contact Viltrox support. They may do some software fix by your reason.

Viltrox says their EF to L adapter isn't designed for the BMCC6K. They didn't give me any more information.

I have one EF zoom that won't work with it, a 28-135 variable aperture and so far the rest do, with the exception where a couple don't open up all the way. One 24mm f 1.4 shows 1.45 on the lcd screen, but I can see that the aperture is actually open all the way. My EF 50mm f1.4 is reading f1.45 in the camera and is actually slightly closed down when I look at the lens aperture. My EF 85 f 1.8 won't open past f 2.0 in the ff, but they all work fine on my eos 20d.

I ordered the Sigma 21 adapter, EF to L to see how that works.

Young Durand wrote:

“I have the viltrox EF-L pro but on the sigma 24-70 f2.8 iris control dont work
…iris control work for my 70-200 and 18-35
On the fotodiox pro fusion ciné iris control work on all my sigma Lens”

Chris Ortenburger wrote:

“Recommendation Needed: I have the 6K FF and am trying to find a lens adapter to go from L to EF *that will allow me to control F stop. I have one that lets me use the glass, but I can't adjust any settings. Anyone have a recommendation for one that will?”

Facebook>Blackmagic Pocket Cinema Camera 4K / 6K Pro Community (BMPCC4K BMPCC6K)

https://www.facebook.com/groups/8821606 ... tid=Nif5oz

I came across this:

Dave Ng complained that with the Sigma MC-21, the EF 50mm F1.4 won’t AF unless he manually focuses before it starts to work.

Dave Ng wrote:

“UPDATE: I've just updated the body firmware and the AF has improved quite considerably. At the extremes from moving far to near it does still cause some issues but if I'm half pressing the shutter button as I move the camera it can get around this. Time to take it out for a test drive.

Just switched over to the S5IIX from Canon, hoping to use my EF lenses. Using the Sigma MC21 converter I was hoping it'll just plug and play nice. However the 50mm 1.4 doesn't want to focus at all unless I manually focus it before it decides to work and also with the 24-70mm? Didn't see that coming as I let go of my Eos R/R7 hoping to be upgrading.

…50mm just doesn't want to play nice unless you do most of the focus and let the camera do the rest.”

Edward CH Light wrote:

“I also have that lovely budget canon 50mm f1.4. Unfortunately that lens remains crippled by Sigma MC-21’s lack of firmware updates since 2019 till now. Everytime i had to rent a Canon R/R6 or using my old 6D for event photography gigs. I’ve heard good thing about Voltrox pro ef-l adapter but i dont see this lens in their compatibility list.”

Ed Dooley wrote:

“The MC-21 is designed to be compatible with certain Sigma EF lenses. Some Canon lenses may they, others may not. Here’s another person’s 50 1.4 not-so-great experience.”

https://www.dpreview.com/forums/thread/4628466

Facebook>Panasonic Lumix S9, S5II/X, S5, S1, S1R, S1H, & BS1H for Video User Group>Dave Ng 7/5/24

https://www.facebook.com/groups/3323226 ... tid=Nif5oz

While looking at the Adorama listing, a reviewer of the Sigma MC-21 said this in 2021:

Works great with manual lenses, could be better for others.
When Sigma says that they only guarantee correct operation with lenses they make themselves, that should be taken seriously as a warning with lenses that aren't fully manual.
This adapter works great with fully-manual Rokinon/Samyang cine lenses. By contrast, I'm not thrilled w/ performance with a Canon f/1.8 50mm, despite the "nifty fifty" being hugely popular -- autofocus is unusably slow, and the camera hung a few times and had to have power removed to get it unstuck during settings adjustments.
It's interesting that the screw mounts are in exactly the right place (to have both camera and lens mount fastened down) when the camera is in a SmallRig cage; when the camera is uncaged, one ends affixing the mount only but not the camera to a tripod.

Another user who rated it with 2 stars posted this in 2020:
Poor compatibility and no AF-C really prevents keeps me from recommending this
Alex R.'s review was spot on. On lenses that have electrical contacts for aperture control, the adapter will cause the lens to stop down every I start and stop shooting video, except for when shooting wide open. I am attaching a video for better understanding.
Sigma - Please update firmware to fix this.

This user rated it as 2 stars in 2019:
Buggy but we don't have any other options
Works well with most lenses. I don't need autofocus for what I do so I don't care about that. However, when I use it with my Rokinon SP 50mm 1.2 the camera only sees it as a f/1.3 and every time I start or stop recording, the aperture closes by one stop. No idea why. I don't want to get rid of my lens. Please metabones make something better.

Sigma MC-21 Mount Converter, Canon EF Lenses to Leica L Mount Cameras

https://www.adorama.com/sgmc21c.html

I also checked the reviews on the BH Photo site:

Tsubasa gave it 3 stars in 2024:
Glitchy
So far, it has been very glitchy. It did not work with Canon 50mm F1.4 non L series lens at all. With Canon EF 17-4- F4.0, it works but hit and miss. What is very annoying is my Lumix S5iix sometimes even recognize the adaptor at all. When I take photos. AF is okay, not amazing. Often time it misses eye focus.

Qin gave it 1 star in 2023:
Canon EF lens is not designed to work with this adapter
I read the review here as well as on YouTube, thought this adapter will work with Canon EF lens. No!!! I have Canon EF 50mm F1.8 as well as EF 35mm F2, both are not working. Then I checked with tech support, and was told this adapter is designed for Sigma EF-mount lens, not for Canon EF-mount lens. So some Canon EF lens will work, but many don't. Check check online. So don't assume this will work with Canon EF lens

Louis gave it 3 stars in 2019:
Not really fully compatible with S1R
Sigma claims that this mount makes certain Sigma Art lenses in Canon mount compatible with the Panasonic S1R, with the exception that continuous autofocus is not supported. This is not true. The focus and aperture bracketing functions of the camera do not work with this adapter. Nor does the Panasonic Lumix tethering program support manual focus when this adapter is used with the Sigma Art 70mm macro lens, which is on Sigma's compatible list. Nor does the linear manual focusing mode of the S1R.

Vincent gave it 3 stars in 2019:
Flop for sigma, its not like a MC11 in L mount!
After 2 weeks of use I found a lot of negative points to this ring! The (-) -Strongly it works better with any other brand than with sigma lens ** .. no AF-C (even for the sigma lens) so the S1 / S1R are very poor in purpose perfectly usable for the moment ** You need to buy the USB sigma dock, update the firmware and its better) - the adapter vignette on some lens even in FF (those who want to put a 18-35 you can forget because the 16-35 f2.8 sticker already good) - No connection for updates (big mystery, will you have to buy another dock L mount in the future ?? ..), -heavy -incompatible with the ronin S focus weel The (+) -stabilization -The setting of the aputure -It is solid -AF-s is fast enough (except with some lens where it gets 100% tilted)
Sigma MC-21 Mount Converter/Lens Adapter (Sigma EF-Mount Lenses to L-Mount Camera)

https://www.bhphotovideo.com/c/product/ ... ml/reviews

Re: Best EF to L adaptor for BMCC6K?

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