Archived posting to the Leica Users Group, 2001/06/15

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Subject: Re: [Leica] is it possible for one M lens to misfocus?
From: shino@ubspainewebber.com
Date: Fri, 15 Jun 2001 17:02:18 -0400 (EDT)

i thank you guys for the advice.

i put a couple of illustrative scans on my site, showing images
taken with my suspect 28, versus my 90.  i made these scans as
quickly as possible, so there is plenty of dust, and tonality has
only been minimally adjusted.  i applied identical amount of sharpening
to all my scanned images with photoshop, and to the canon CD scans
with gimp.

http://www.shinozuka-family.com/testphotos

~/public_html/testphotos $ ls -lt
total 4940
- -rw----r--  1 shino  users  1608334 Jun 15 16:41 trees28.jpg
- -rw----r--  1 shino  users   710288 Jun 15 16:31 robots90.jpg
- -rw----r--  1 shino  users  1129158 Jun 15 16:26 playroom28bad.jpg
- -rw----r--  1 shino  users   242007 Jun 15 16:24 color28.jpg
- -rw----r--  1 shino  users   203170 Jun 15 16:23 color90.jpg
- -rw----r--  1 shino  users  1126408 Jun 15 16:19 greenwich28.jpg

you can see, these are BIG files.

set 1. color28.jpg and color90.jpg are 1536x1024 canon hyperphoto CD scans,
       taken on the same day on fuji800  with the m6 and 28mm and 90mm
       respectively.  the 28mm image is just not crisp.  both around f8.

set 2. playroom28bad.jpg and robots90.jpg are delta 100 scanned on my
       minolta dimage scan multi to 2200x1760, were taken on the same
       day as each other with the 28 and 90mm.  the playroom28bad
       is just bad, but robots90 show the m6 to be focusing well.
       both f4-5.6.

3.     to show why i USED to think the 28 was such a great lens, is
       greenwich28.jpg taken in 1988 on XP1, scanned identically to set 2.
       probably around f8.

4.     finally, just to confuse things, i have a 28mm image on the same roll
       as set 2 (delta 100), which seems to be a decent shot (except for
       wind motion)  this was taken at f8, scanned identically to set 2.

the set 1 and set 2 images are VERY representative of the results i am
getting.  if it were only 1 or 2 images that were out-of-focus, i would
attribute to user error.  but they ALL look like this.

does this look like a focus problem with the lens?  or something else?

thanks very much for any advice you may offer.

- -rei


> From: V8PWR@aol.com
> 
> Dans un courrier daté du 15/06/01 19:21:07 Paris, Madrid (heure d'été), 
> shino@ubspainewebber.com a écrit :
> 
> > i have an m6 and the following lenses: (dates are design year, as per Puts)
> >    2.8/21 Elmarit-M 1980
> >    2.8/28 Elmarit-M (III) 1979
> >    1.4/35 Summilux-M, 1961
> >    2.0/90 Summicron-M (III), from 1980
> >  
> >  i used to think the 28 was the sharpest of these lenses, but lately
> >  i've been surprised to see images made on this lens have looked very
> >  mushy and soft.  from examining some of these images, i suspect
> >  that the 28 is focusing well ahead of the rangefinder.  my other
> >  lenses on the same camera seem fine, even the 90.  if the m6's
> >  rangefinder were off, i'd expect images on the 90 to be affected the most,
> >  but my photos with the 90 are pretty well dead-on focus.
> >  
> >  so, is it possible on an M that the focus on one lens is off?  i suppose
> >  i could give the whole kit over to leitz, but realistically
> >  that would mean being without the stuff all summer (shudder!).
> >  
> >  any advice to a guy who may need to use an F3 all summer?
> >  
> >  thanks,
> >  
> >  -rei
> >  
> >  
> I've always wondered how a 28 Leica can be off by so much .
> What has changed in it ? It must have been desassembled ,
> and wrongly reassembled , cause the rear ring , contacting 
> the body roller , cannot be worn so much .
> But I'd rather send Leica stuff for 6 months instead of using 
> it knowing it is so much faulty .
> 
> JO GOODTIMES -FRANCE/ AIRBORNE RADAR TECH / LIVE FREE OR DIE
> will soon walk with mud covered combat boots...
>