M8 1.4/50mm ASPH. backfocus blues!

[Arne Helme]

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Being a long time user of M cameras and lenses I have always enjoyed using the lenses at their widest apertures knowning that the M body is sufficiently accurate to let me set the correct focus. In most cases I focus either in the near range og 0.7m-4-5m, or at infinity. Simple.

 

WIth the M7 I am usually spot on with the focus about 80% of the time using the 2.0/28mm ASPH., 1.4/35mm ASPH. and 1.4/75mm lenses. With the M8 a little less so as it seems that it must be focused more accurately than the M7 in order to exploit the true potential of the lenses. However, after 3 months with the M8 I am now quite confidently using the camera with my lenses and the level of sharpness that I expect from the lenses.

 

About a year ago I acquired a Summilux-M 1.4/50mm ASPH. LHSA edition lens. It did not get that much use before I got the M8. That's also about the time the blues started. After a couple of months using this lens my suspicion about the lens was backfocusing started to grow. While I still got lots of sharp photos with the other lenses, most shots with the 50mm, wide open and stopped down, were brilliantly sharp BEHIND the subject that I had focused on.

 

The lens went back to Solms for installation of a 6-bit decoder and to be readjusted. It came back with the new 6-bit decoder installed but still backfocusing.

 

I looked at the other threads in this forum discussing backfocusing and decided to give camera adjustment a try. I little bit of experimentation and adjustments with the Allen hex key and, VOILA, all photos shot wide open with the 1.4/50mm ASPH. were brilliantly sharp EXACTLY where I focusing in the near range. The imagery at 1.4 with this lens is truly stunning when correctly focused!

 

Now the problem, of course, turned to be that all my other M lenses did not correctly focus anymore !

 

So, I readjusted my camera again for the other lenses, plus a 1.4/50mm ASPH. that is backfocusing. I guess sending it back again to Solms is my only option. It is sad to say, but a backfocusing lens is for me simply not usable. Therefore it seems as if I will have the 1.4/50mm ASPH. blues for at least another two months until the problem HOPEFULLy has been fixed!

 

Sigh!

 

-- Arne

[Guest Olof]

sure that its a backfocus problem and not a focus problem ? For the 50mm 1.4 the Leica 1.25 Magnifier is very helpfull, i use it and now focusing is much easier.

[Arne Helme]

sure that its a backfocus problem and not a focus problem ? For the 50mm 1.4 the Leica 1.25 Magnifier is very helpfull, i use it and now focusing is much easier.

 

Yes, I am quite sure of that. I forgot to say that I am already using the 1.25mm Magnifier. It helps tremendously with the the other lenses except for the 1.4/50mm ASPH...

 

I also did test the lenses using a tripod and the focus test chart. The lens is consistently backfocusing compared to the other lenses.

 

-- Arne

[Guest Olof]

Yes, I am quite sure of that. I forgot to say that I am already using the 1.25mm Magnifier. It helps tremendously with the the other lenses except for the 1.4/50mm ASPH...

 

I also did test the lenses using a tripod and the focus test chart. The lens is consistently backfocusing compared to the other lenses.

 

-- Arne

 

 

OK, than ist a problem between your M8 and your lens. I use the same combination without problems

[B&W]

I did send my M8 to Solm for adjustment of back focus

It did back focus with both my lenses 35 cron asph and 50 lux asph

I got it back last week and the 35 cron is spot on and the 50 lux is still back focusing, but it’s better just not perfect

 

I even bought a Leica viewfinder M 1,25 to get the focus correct but it’s doesn’t work for me with my spectaculars – I’m not able to se the LEDS

[charlesphoto99]

The infinity focus adjustment is not the "quick fix" that's been advertised on her. It's a fine play between that and the near far focus adjustment, which is the screw at the end of the arm, which when loosened, one can adjust the length of the arm by moving the washer underneath. See Carstenw's post on the subject.

 

I've spent several hours carefully adjusting the two - they are not independent of each other and without sophisticated equipment it's a matter of trial and error. problem was I would get the near and far focus of the rangefinder spot on and then the mid focus would be off. Finally got it to where it works, using a 90 APO as my guide lens, though my 35 1.4 asph backfocuses still from about f4 on up and my 28 Summicron needs adjustment from a previous repair by Leica - it won't focus properly at infinity (and therefore somehwta at other distances), something I just never noticed with my film Ms. My 50 pre-asph summilux 2nd version backfocuses horribly from wide open on out and will either need adjustment or be sold. My worry is adjusting via shims etc to the M8 will render it useless on M7 etc.

 

I think there's no magic bullet here. Some lenses will focus better than others, and adjusting the camera to a particular lens may render it useless with other lenses. Not sure if Leica or anyone will be able to figure the answer on this. Hopefully they will. And digital is a lot less forgiving than film.

[ARARAT4]

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I do have exactly the same problem. My LHSA 50 summilux aspherical back focus (about 5 cm at 3 meters) while all my other lenses are spot on (90 summicron asph, 50 summilux pre asph and 35 summicron asph). I tried adjusting the infinity cam on the M8 and I can make the 50 summilux asph spot on, but all the other lenses are slightly out of focus. And I do use the 1.25 magnifier. Leica UK tells me I need to send both the Summilux asph and the M8 together to Solms, but my worry is that they will fix one problem and create another with the rest of the lenses. Which mean that I will probably send everthing to them and worry about £8,000 in hte post for 4-8 weeks.

 

Ala

[Jamie Roberts]

Is there no local Leica or camera guru in the UK?

 

I ask because I'm about to take my 75 Lux and 35 Lux into Kindermann Canada for a full adjustment with the M8. The 75 because it front focusses a bit; the 35 so they don't mess that up!!!

[glenerrolrd]

I do have exactly the same problem. My LHSA 50 summilux aspherical back focus (about 5 cm at 3 meters) while all my other lenses are spot on (90 summicron asph, 50 summilux pre asph and 35 summicron asph). I tried adjusting the infinity cam on the M8 and I can make the 50 summilux asph spot on, but all the other lenses are slightly out of focus. And I do use the 1.25 magnifier. Leica UK tells me I need to send both the Summilux asph and the M8 together to Solms, but my worry is that they will fix one problem and create another with the rest of the lenses. Which mean that I will probably send everthing to them and worry about £8,000 in hte post for 4-8 weeks.

 

Ala

How can you be sure you have set the focal point accurately? I worked on this both on a tripod and hand held ..using 3 different lenses. Made significant improvements by adjusting infinity (the cam) ..but I had to back it off just a degree or two to achieve accurate close focus ..its much better than it was. Having taken several hundred test images...I realized that handheld best I can do is within 10-15cm. At 3 meters can you really be sure you focused accurately within 5 cm ?

[tom0511]

My 50/1.4asph also backfocused on my M8, I sent it to Leica for adjustment and it now is spot on.

Still not all ofmy lenses are perfect in focus, and some which are perfect on my rd1 are not on my M8.

The funny thing is that my longer lenses (50,75,90) seem to work perfect and more accurate than the wider. However my wider lenses seem to be close enough that its not a problem.

The only I am not sure is my 35/1.4asph after being coded. Seems to show some backfocus.

[guywalder]

My 50/1.4asph also backfocused on my M8, I sent it to Leica for adjustment and it now is spot on.

QUOTE]

 

Thomas,

did you send the lens or the camera back?

My experience is similar to Arne's. I have had a 50 lux ASPH for a while, not used in much on my M7, although when I did I always wondered about the focus.... now I can easily see that the M8/50 combination is off, which makes me sure the lens is at least partly at fault (confirming my suspicions from the M7). But my 28summicron is also a little off on the M8 as well although it is at least useable between infinity and, say, 1.5m

All rather frustrating...

Guy

[ARARAT4]

How can you be sure you have set the focal point accurately? I worked on this both on a tripod and hand held ..using 3 different lenses. Made significant improvements by adjusting infinity (the cam) ..but I had to back it off just a degree or two to achieve accurate close focus ..its much better than it was. Having taken several hundred test images...I realized that handheld best I can do is within 10-15cm. At 3 meters can you really be sure you focused accurately within 5 cm ?

 

I myself have thought that it would would be very difficult to reproduce cosistently but it was fairly reproducible especially with the two summilux lenses. I have used 3 similar small boxes with a big barcode set in a diagonal one behind the other with a variable distance (between 1-5 cm) and focused on the middle one. This would be very difficult to do with my MP but with the M8 it is much easier. One has to be consistent with the focusing and that required some experimentation.

 

Ala

 

P.S. the distance was not exactly 3 meters, but probably more lik 2.5 meters.

[ARARAT4]

How can you be sure you have set the focal point accurately? I worked on this both on a tripod and hand held ..using 3 different lenses. Made significant improvements by adjusting infinity (the cam) ..but I had to back it off just a degree or two to achieve accurate close focus ..its much better than it was. Having taken several hundred test images...I realized that handheld best I can do is within 10-15cm. At 3 meters can you really be sure you focused accurately within 5 cm ?

 

I myself have thought that it would would be very difficult to reproduce cosistently but it was fairly reproducible especially with the two summilux lenses. I have used 3 similar small boxes with a big barcode set in a diagonal one behind the other with a variable distance (between 1-5 cm) and focused on the middle one. This would be very difficult to do with my MP but with the M8 it is much easier. One has to be consistent with the focusing and that required some experimentation.

 

Ala

 

P.S. the distance was not exactly 3 meters, but probably more lik 2.5 meters.

[pemayeux]

My 50 lux ASPH and my 75 lux backfocus. I sent them to Leica NJ and they verified that they were off and now they are on their way to Solms. Hopefully I'll get them back before Christmas. It took the NJ office a month just to verify that the lenses need to go to Solms.