EF-M Adpter: Focus problems

cr2shooter wrote:

I have the same problem.
- M6 II
- Viltrox EF-M adaptor
- Canon 50mm f1.8 STM
- Camera settings: One Shot AF, AF Method is the square (don’t know its name), - Continuous AF disabled
Sometimes the lens won’t focus correctly when I press the focus button. You can hear the lens being jolted electrically and then the focus indicator beeps but enlarging the image shows it’s not in focus. Yet on other occasions it works perfectly. The Canon EF-M 32mm/1.4 and 22mm/2 work perfectly all the time.

I’ve tried other focus settings like continuous AF but the fault is still there.

I guess you’d have to eliminate that adapter from the equation, and try a genuine Canon adapter. I don’t have the Viltrox adapter, and I sold my EF 50 STM, so I can’t do any testing for you unfortunately.

The Fotodiox Pro adapter (and my Canon adapter) don’t have focus issues, and didn’t with the 50 STM. However the Fotodiox Pro adapter does suffer from the “internal reflection” issue (resulting in flare and veiling glare), so I’d avoid that one.

Maybe someone with your particular combo can jump in here.

R2

R2D2 wrote:

Robert Seetzen wrote:

istscott wrote:

I don't have any answers, but I did buy a new Canon 85mm f/1.8 stm that had inconsistent focus accuracy with the official adapter. Though the 50mm f/1.8 stm I have works well.

Oh, that doesn't sound good. Up until now I was hoping that these problems would be limited to lenses from other manufacturers - (...)

I’d avoid conflating issues here. You’ll muddy the waters and then never find your way out.

For now stick to determining why your Tamron lenses are misbehaving. Have they offered any solutions yet?

(...)

I’d reiterate that I don’t think your issue lies with the adapter (and the body is proven). Take it from there...

Best of luck!

R2

The lens is still with Tamron. I spoke with the service department yesterday and was told that the lens is within the tolerances, but they still want to try a better adjustment. Basically, however, they are aware of focus problems with the mirrorless systems of all manufacturers.

I've since sold my M5 body and used the proceeds to buy a 70D with the 18-135 STM - partly because of the apparently pretty good lens included in the low price and partly because I simply want the option of micro adjustments for any problematic lenses.

My 50mm f2.8 Macro sent to Sigma service is apparently also out of adjustment. I'm curious to see how it will behave after repair on the M50 and 70D.

The Sigma 28-135 f3.8-5.6 Macro clearly gives better results on the 70D than on the M50 - without any micro adjustments. This is another reason why I wonder if the problems are not at least partly due to undisclosed or unsuccessfully reverse engineered details of the EF control protocols.

cr2shooter wrote:

I have the same problem.
- M6 II
- Viltrox EF-M adaptor
- Canon 50mm f1.8 STM
- Camera settings: One Shot AF, AF Method is the square (don’t know its name), - Continuous AF disabled
Sometimes the lens won’t focus correctly when I press the focus button. You can hear the lens being jolted electrically and then the focus indicator beeps but enlarging the image shows it’s not in focus. Yet on other occasions it works perfectly. The Canon EF-M 32mm/1.4 and 22mm/2 work perfectly all the time.

I’ve tried other focus settings like continuous AF but the fault is still there.

Do you have an opportunity to test the lens on an SLR? Just to be sure it's not a problem with the lens itself?

R2D2 wrote:

cr2shooter wrote:

I have the same problem.
- M6 II
- Viltrox EF-M adaptor
- Canon 50mm f1.8 STM
- Camera settings: One Shot AF, AF Method is the square (don’t know its name), - Continuous AF disabled
Sometimes the lens won’t focus correctly when I press the focus button. You can hear the lens being jolted electrically and then the focus indicator beeps but enlarging the image shows it’s not in focus. Yet on other occasions it works perfectly. The Canon EF-M 32mm/1.4 and 22mm/2 work perfectly all the time.

I’ve tried other focus settings like continuous AF but the fault is still there.

I guess you’d have to eliminate that adapter from the equation, and try a genuine Canon adapter. I don’t have the Viltrox adapter, and I sold my EF 50 STM, so I can’t do any testing for you unfortunately.

The Fotodiox Pro adapter (and my Canon adapter) don’t have focus issues, and didn’t with the 50 STM. However the Fotodiox Pro adapter does suffer from the “internal reflection” issue (resulting in flare and veiling glare), so I’d avoid that one.

Maybe someone with your particular combo can jump in here.

R2

To me, the Viltrox adapter seems to be almost identical with the one from Canon. Even small details in the detachable tripod adapter are identical. I wonder whether they are manufactured in the same plant.
Anyway, to my best knowledge, the adapters do nothing more than to forward the electrical connectors in a 1:1 manner. So besides some possible production tolerances, any adapter that fits the mechanical EF and EF-M specs should deliver the same results.

Or am I wrong and the EF-M adapters are in fact more than just metal and a few wires?
I'd think that it would be interesting to test the f1.8 not only with a different adapter, but with an SLR, too.

Robert Seetzen wrote:

R2D2 wrote:

cr2shooter wrote:

I have the same problem.
- M6 II
- Viltrox EF-M adaptor
- Canon 50mm f1.8 STM
- Camera settings: One Shot AF, AF Method is the square (don’t know its name), - Continuous AF disabled
Sometimes the lens won’t focus correctly when I press the focus button. You can hear the lens being jolted electrically and then the focus indicator beeps but enlarging the image shows it’s not in focus. Yet on other occasions it works perfectly. The Canon EF-M 32mm/1.4 and 22mm/2 work perfectly all the time.

I’ve tried other focus settings like continuous AF but the fault is still there.

I guess you’d have to eliminate that adapter from the equation, and try a genuine Canon adapter. I don’t have the Viltrox adapter, and I sold my EF 50 STM, so I can’t do any testing for you unfortunately.

The Fotodiox Pro adapter (and my Canon adapter) don’t have focus issues, and didn’t with the 50 STM. However the Fotodiox Pro adapter does suffer from the “internal reflection” issue (resulting in flare and veiling glare), so I’d avoid that one.

Maybe someone with your particular combo can jump in here.

R2

To me, the Viltrox adapter seems to be almost identical with the one from Canon. Even small details in the detachable tripod adapter are identical. I wonder whether they are manufactured in the same plant.
Anyway, to my best knowledge, the adapters do nothing more than to forward the electrical connectors in a 1:1 manner. So besides some possible production tolerances, any adapter that fits the mechanical EF and EF-M specs should deliver the same results.

Or am I wrong and the EF-M adapters are in fact more than just metal and a few wires?
I'd think that it would be interesting to test the f1.8 not only with a different adapter, but with an SLR, too.

We've learned however that all adapters are not created equal. 

There's a separate known (not AF) issue with internal reflections in some adapters, caused by either the internal paint, baffles, or opening.  This causes flare and veiling glare (loss of contrast).  Here's an earlier thread detailing the issue...

https://www.dpreview.com/forums/thread/4324738#forum-post-64795450

I only use the Canon adapter now.

R2

Robert Seetzen wrote:

R2D2 wrote:

Robert Seetzen wrote:

istscott wrote:

I don't have any answers, but I did buy a new Canon 85mm f/1.8 stm that had inconsistent focus accuracy with the official adapter. Though the 50mm f/1.8 stm I have works well.

Oh, that doesn't sound good. Up until now I was hoping that these problems would be limited to lenses from other manufacturers - (...)

I’d avoid conflating issues here. You’ll muddy the waters and then never find your way out.

For now stick to determining why your Tamron lenses are misbehaving. Have they offered any solutions yet?

(...)

I’d reiterate that I don’t think your issue lies with the adapter (and the body is proven). Take it from there...

Best of luck!

R2

The lens is still with Tamron. I spoke with the service department yesterday and was told that the lens is within the tolerances, but they still want to try a better adjustment. Basically, however, they are aware of focus problems with the mirrorless systems of all manufacturers.

That's in line with multiple reports over the years (re: Tamron).  Some folks have had great results, some poor.

I've since sold my M5 body and used the proceeds to buy a 70D with the 18-135 STM - partly because of the apparently pretty good lens included in the low price and partly because I simply want the option of micro adjustments for any problematic lenses.

Hey, I shot with that combo for 5 years. 

A great camera indeed.  However I actually went in the opposite direction and sold it for the M5 (and EF-M lenses).  I'm now shooting the M6ii.

My 50mm f2.8 Macro sent to Sigma service is apparently also out of adjustment. I'm curious to see how it will behave after repair on the M50 and 70D.

Wish you the best there.

The Sigma 28-135 f3.8-5.6 Macro clearly gives better results on the 70D than on the M50 - without any micro adjustments. This is another reason why I wonder if the problems are not at least partly due to undisclosed or unsuccessfully reverse engineered details of the EF control protocols.

That sounds odd indeed.  An outlier.

Well best of luck to you!  Happy shooting with your new kit!

R2