Re: [Leica] This sucks -- possible summicron problem

[SthRosner@aol.com]

Good morning Derek!

I was aware that this was a not-uncommon problem with some of the pre-ASPH 35 
Summicrons; earlier examples of this lens did not have locking rings and this 
fact permits the unscrewing of the entire lens cell from the focussing mount. 

By wild coincidence, I had just posted my response to Oliver's inquiry about 
the 35/3,5 Summaron citing Dick Gilcreast's article. I have just spoke with 
Dick about your problem. He said it is almost certain that someone had 
unscrewed the lens cell. It is possible that the lens cell (the optical 
portion) has been put back in a focussing mount diffeent from the one with 
which it was supplied by the factory. Dick suggests that to test if the lens 
is functioning properly, you can take some photographs wide open of objects 
at infinity and see if the centers of the resulting images are sharp. If so, 
you should have no functional optical problem with this lens. 

If the lens is functioning properly, as to the lens shade issue, he suggests 
getting a 35/1,4 Summilux shade that is round and so won't foul or interfere 
with the image, not to mention the effect on the psyche of the displaced 
rectangular shade.

If the lens is not functioning properly, it really should go back to the 
place from which it came for replacement or refund. Otherwise, it is possible 
that Leica USA or Solms can fit the lens cell with a correct focussing mount. 

Hope this has been helpful.

Seth            LaK 9   (incidentally, for those who have been wondering and 
those who have read this morning's post on the 35/3,5 Summaron, LaK 9 is the 
designation for the lanthanum crown glass that the Leitz glass laboratories 
invented in the late 1940s or early 50s and that led to the breakthrough 
design of the 50/2 DR Summicron, the first 35/2 and 90/2 Summicrons and a 
bunch of contemporary Leitz lenses).  

In a message dated 3/15/02 8:57:51 PM Eastern Standard Time, derek@zeanah.com 
writes:

> OK, I'm back in the world of M cameras -- I traded some Nikon gear for an 
M6 
>  and a 35 pre-asph Summicron.  Everything seems to work great -- test pics 
>  came back fine and everything, and I think I got some *great* shots last 
>  night.
>  
>  But tonight I put the 35 back on the camera (also have a 90 and 50) and 
saw 
>  this: http://derekzeanah.no-ip.org/summicron
>  (it's a DSL line limited to 20k uploads, but I tried to keep the images 
>  small.  Yes they suck, no I don't care right now.)
>  
>  Basically, the lens shade rests lop-sided on the lens normally; I can 
twist 
>  it back, but it looks like I'm unscrewing the front element of the lens 
when 
> 
>  I do so, and having everything line up properly isn't finger tight (though 
> it 
>  might be tight enough not to notice for 2 days, as is going on here).
>  
>  Please tell me this is something that's easy to correct.  In-house.  
Tonight 
> 
>  so I've still got the camera in-hand tomorrow.
>  
>  Please!
>  
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