35/1.4 Summilux-M ASPH 11874 with film
Old 06-26-2019   #1
F456
Tom H
 
F456 is offline
Join Date: Jul 2007
Location: UK
Posts: 137
35/1.4 Summilux-M ASPH 11874 with film

I have a 35/1.4 which is the first version ASPH lens (i.e. the version that first came after the very expensive Aspherical). I first used it with an M8 12 years ago and yes I did notice some focus issues on digital.

The lens has hardly been used since then but is in fine condition and I am about to shoot with it again but this time I only shoot with film Leicas.

As I don't have time to experiment, field test etc before going for my next shoot I am hoping someone might confirm what I suspect -- that the lens will be absolutely fine with film as far as focus goes. Leaving aside that the more recent lenses are probably better, is the problem solved entirely when shooting film rather than digital with this lens? Presumably so, as it was designed for film use, but it would be nice to hear from regular users. Thank you. (I have been shooting with my old 35/1.4 original style little Summilux but I want a different look for a while in low light and could be using all the critical apertures i.e. slightly stopped down between fully open and about f/4 when not in use for daylight shooting.) Thank you.

Tom
  Reply With Quote

Old 06-26-2019   #2
Freakscene
Deregistered user
 
Freakscene's Avatar
 
Freakscene is offline
Join Date: Aug 2006
Location: In exile
Posts: 1,621
Quote:
Originally Posted by F456 View Post
is the problem solved entirely when shooting film rather than digital with this lens?
No. The focus shift is exactly the same - focus shift is an optical property of the lens and has nothing to do with the camera or recording medium. But - film just shows focus shift less clearly because of the depth of the recording medium, lower sharpness and lesser enlargeability.

I still like and use this lens with film.

Marty
  Reply With Quote

Old 06-26-2019   #3
F456
Tom H
 
F456 is offline
Join Date: Jul 2007
Location: UK
Posts: 137
Quote:
Originally Posted by Freakscene View Post
No. The focus shift is exactly the same - focus shift is an optical property of the lens and has nothing to do with the camera or recording medium. But - film just shows focus shift less clearly because of the depth of the recording medium, lower sharpness and lesser enlargeability.

I still like and use this lens with film.

Marty
Marty,

Thank you. In your way of working do you consciously avoid certain apertures or adjust your focus to compensate? I suppose I am just wondering if the acceptability for you is a result sometimes of a work around. Am I right in thinking that at full aperture, assuming I have focused accurately there should be no problem? And that beyond a certain aperture the problem is pretty much dealt with by depth of field? Just checking to be sure!

Thanks for your fast response!

Tom
  Reply With Quote

Old 06-27-2019   #4
Doug
Moderator
 
Doug's Avatar
 
Doug is offline
Join Date: Sep 2003
Location: Pacific NW, USA
Posts: 13,018
I got that same lens model from Robert White Ltd back in 2009, and was dissatisfied with the focus on both an M8 and Konica Hexar RF film camera. It was not really a matter of focus shift, rather it seems the lens was not set up correctly at the start. My note regarding use on the Hexar RF:

"Lens needs focus adjustment; focusing well behind intended point both wide open and at mid-apertures. If desired focus is 3ft, then best sharpness is abt 4ft; same if doubled; but if focusing at 50 ft, then not even far distance is sharp."

So I sent the lens, along with several others, to DAG for focus check and adjustment, and he replied that all were in need of focus adjustment. After he made the adjustment, the focus was correct, at least on the M8 and M9 but it was not used on the Hexar after that. I never noticed any focus shift myself.

Similarly I recall DAG adjusting the focus on my 1.5/50mm C-Sonnar which is notorious for focus shift. Wide open at 8-10' distance I'd lean forward slightly (an inch or so) after focusing to bring the focus to where I wanted it. It was right-on at f/2.8. DAG made it right-on at f/2 - f/2.2 and ever since I've been able to simply ignore the issue, as the shift is so minimal.
__________________
Doug’s Gallery
RFF on Facebook
  Reply With Quote

Old 06-27-2019   #5
Freakscene
Deregistered user
 
Freakscene's Avatar
 
Freakscene is offline
Join Date: Aug 2006
Location: In exile
Posts: 1,621
I have found, sadly, that if you don't have your digital Leica and your lenses calibrated every few years (depending on how much and how hard you use them) focus calibration wanders.


Okavango Delta - Leica MP 1/250, 35 Summilux ASPH @ f5.6 medium yellow filter, Tri-X in Xtol 1+3.

Focus shift occurs more in lenses with certain kinds of residual spherical aberrations. As the aperture changes, the point of focus changes (shifts).

Lens designers always have to make compromises. The distribution of the field of acceptable sharpness depends on the focal length of the lens. Shorter focal length lenses always have less depth of field in front of the subject than longer focal length lenses, but they have more depth of field behind the subject than longer focal length lenses. At close range and wide open the focus point of an 11874 as Leica designed it to be calibrated is ever-so-slightly in front of the point at which you focus. As you stop down the focus point shifts away from the film/sensor plane. When the shift is greater than the increase in depth of field this causes out-of-focus photos.

In practice with the 11874 if you avoid using the lens at distances <3m at f2.8 and 4 it will be a minimal problem. I understand that you want to use the lens on film, but if you have access to a digital M and a focus checker, you can take lots of photos fast at different apertures and distances with a focus checker like this: http://michaeltapesdesign.com/lensalign.html and see the difference.

But enjoy. It's a great lens.

Marty
  Reply With Quote

Old 2 Weeks Ago   #6
agoglanian
Reconnected.
 
agoglanian's Avatar
 
agoglanian is offline
Join Date: Jun 2005
Location: San Francisco, CA
Age: 33
Posts: 929
I'm still getting to know my copy of the lens, but mine is a 2000 production date and was 6-bit coded at some point so I'm guessing it got calibrated when the service was done.

It has been very easy for me to predict any focus shift on both digital and film I find that at my normal working distance it is hardly even noticeable. If I were to test very specifically looking for focus shift then I do see it but in actual use it's just a non-issue for me personally.

I've started to just counter for it by just slightly adjusting my focus forward and that always seems to land my focus exactly where I want it.
__________________
- Abram

M-A | M10 | Q | 500CM

Instagram. | Website.
  Reply With Quote
Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is On
HTML code is Off



All times are GMT -8. The time now is 21:35.


vBulletin skin developed by: eXtremepixels
Powered by vBulletin® Version 3.6.8
Copyright ©2000 - 2019, Jelsoft Enterprises Ltd.

All content on this site is Copyright Protected and owned by its respective owner. You may link to content on this site but you may not reproduce any of it in whole or part without written consent from its owner.