[Leica] Fogging film during lens changes

[len-1 at comcast.net (Leonard Taupier)]

Rob,

I've never had fogging with my IIIC, IIIF or any of my M bodies.  
Nearly all of my photography is outdoors and I change lenses often. I  
never pay attention to where the sun is when I only change a lens.  
I'm very surprised Sherry made a comment like that. I just looked at  
over 80 sheets of bw negatives and didn't find one single fogged  
frame. Most of my film was ISO 100 or 125 though. What film do you use?

Len


On Oct 8, 2007, at 7:20 PM, Robert Lilley wrote:

> I am relatively newbie to the Leica world and I've been going crazy  
> trying
> to figure out what gives with my screw mount Leica stuff.  Various  
> frames on
> a roll would be fogged seemingly at random.  I thought it was my  
> Leica IIIa
> body or the Summicron 50mm as it always seemed to happen around the  
> use of
> that lens.
>
> I changed Leica bodies to the older Leica II and did a test roll  
> with all my
> Leica lenses and figured it out.  It's not the lenses or the  
> bodies; it's in
> the lens changes.  Apparently Leica shutter curtains are  
> susceptible to
> stray light.  Sure enough, every time I changed lenses the last  
> frame shot
> got another dose of fogging light whilst the next frame shot with  
> the new
> lens was fine.  Of course it always happened around use of the  
> Summicron -
> it wasn't the Summicron, it was the shot just before the change  
> back that
> got fogged.  Called Sherry Krauter, noted Leica repair person and  
> she said,
> "Oh, yea, you didn't know that - happens with all the screw mounts  
> and M's!?
> I said, "Why doesn't this happen with Japanese cameras, etc?" and she
> shrugged (imagined), "That's just the way it is".
>
> Being a longer time Exakta user I voiced my woe to that group and  
> got the
> following reply:
>
> "I was using my Version 1 Varex IIa last week for an entire  
> cartridge and I
> used four different lenses. I don't know how many changes it was,  
> but it was
> more than three or four because I was using my 80mm Biometar most  
> of the
> time. It was the "user" lens and I switched to a 35mm and a 100mm  
> and a
> 150mm. The mirror was up all the time when I was changing the  
> lenses, of
> course, and it was extremely bright sunlight, and I had no  
> fogging.  In fact
> I have never had fogging except when there was a sprung back or bad
> weather-stripping on a camera requiring it.  Considering all the
> photojournalists and other professionals who used Leicas switching  
> lenses
> all the time, I can't imagine they put up with this fogging business
> changing lenses. Although that is my conjecture.  But it seems like  
> we would
> have read about it if it was an inescapable fact of cloth focal plane
> shutters without instant return mirrors."
>
>
>
> I have to agree with the above and wonder if this is something that  
> can be
> corrected as both of my Leica bodies are screw mount and pre-war.   
> Newer
> bullet proof curtains?!   What say you all?  Thanks for your time.
>
>
>
> Rob
>
>
>
>
>
>
>
>
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