Focus shift with Canon 50mm 1.2 and M8

[OurManInTangier]

I recently bought a Canon 50mm 1.2 and have been using it with my M8, at first I thought that the lens was simply very soft or that my hands were even shakier than I had assumed!

However, having tested the two together using a tripod and the self timer with some very careful focusing I've found that the focus seems to be out by several inches. The lens seems to actually focus on a point some 8 inches beyond the intended point of focus.

Has anyone else had a similar problem with this combination? I have heard that some lenses may need to be calibrated to be used with the M8 or 'shimmed.' Does this sound like a typical example or a problem with the lens itself?

Does anyone know of a decent place in the UK that could perform the necessary calibration? What potential effect this could have on using the M8 with other lenses or the 1.2 with other cameras? Plus, what sort of cost we may be talking about?

Sorry for all the questions!

Many Thanks

 

[Hacker]

I sent my lens to DAG. Cost me US$150 + US$50 return shipping for an overhaul.

 

[OurManInTangier]

I sent my lens to DAG. Cost me US$150 + US$50 return shipping for an overhaul.

So you just need to send the lens?

I'll have to take a look at the DAG website, assuming there is one. If anyone else has any advice, experiences or suggestions I'd be grateful to hear them.

 

[Mackinaw]

This problem (certain lenses either over-or-under focusing on the M8) has been covered big-time on the Leica forum. Several M8 owners have fixed things themselves by readjusting the rangefinder cam in the camera itself. If you insert an allen wrench into the cam (take off the lens and look at the mechanism) and turn it a few degrees, you can solve many of the focusing problems. Here's the thread:

http://www.l-camera-forum.com/leica-forum/leica-m8-forum/13933-new-backfocus-thread-solution.html

Jim B.

 

[Keith]

I remember checking four lenses on my M8 one night for focus accuracy ... my 1.2 Nokton ~ 50mm Hex and 35mm Hex along with my 1.2 Canon. The results weren't good but it was mainly an issue at the minimum distances ... I try not to think about it!

 

[OurManInTangier]

This problem (certain lenses either over-or-under focusing on the M8) has been covered big-time on the Leica forum. Several M8 owners have fixed things themselves by readjusting the rangefinder cam in the camera itself. If you insert an allen wrench into the cam (take off the lens and look at the mechanism) and turn it a few degrees, you can solve many of the focusing problems. Here's the thread:

http://www.l-camera-forum.com/leica-forum/leica-m8-forum/13933-new-backfocus-thread-solution.html

Jim B.

Thanks Jim, I'll scour the threads for more info. Though i'm not sure I want to adjust my M8 just for one lens as all my others are fine. I'll have to check the 50mm 1.2 on one of my M6 bodies and see what the focus is like there.

Thanks again

 

[rxmd]

If all lenses are focusing fine, and just one lens is off, it seems to me that one should adjust the lens rather than the camera.

 

[OurManInTangier]

If all lenses are focusing fine, and just one lens is off, it seems to me that one should adjust the lens rather than the camera.

This would appear to be the sensible course of action

 

[OurManInTangier]

I've just got back from a camera repairman I know who has tested all of my lenses on my M8 and on one of my M6 bodies ( yep, he's an absolute star as he just fitted me in around everything else he was doing.)

The upshot is that both my Canon 1.2 and 1.8 lenses are absolutely on the mark, as is my Summicron v.4 and the CV Ultron 1.9....my CZ 50mm Planar is however fractionally out at infinity, which surprised me as I expected the 1.2 to have all the problems.

It seems my m8 had a slight back focusing problem that was only really picked up when I bought the 1.2 and started shooting it wide open to test it out. I rarely shoot wider than f4 as I like to have some context for the focus of my pictures so it didn't really show up. I've now adjusted the RF on my M8 and everything seems to be working perfectly so I'd like to thank everyone for their suggestions and especially Jim for the link to the thread that helped me so much.

 

[kevin m]

Wow, congrats on getting this resolved so quickly! I know of many people who sent their entire M8 kits to either DAG or Leica Germany and didn't see them again for weeks. Merry Christmas to you.... 😀

 

[OurManInTangier]

Thanks Kevin!

Maybe if I'd sent my gear off somewhere I'd have the same wait as everyone else. Thankfully this guys a great find. He works on all my work kit as well as many other Pro guys I know though he does specialise in SLR gear. He did all the checking and told me what the problem was and gave me the choice of send the M8 away, leave it with him to do in the next three weeks or do it myself. I ended up taking it home and using a 2mm flathead screwdriver to make the adjustment...not exactly the master craftsman but hey, it worked!