[Leica] Fogging film during lens changes

[grduprey at mchsi.com (grduprey@mchsi.com)]

Hi Rob,

Never seen this with any of my M cameras.  I have Russian Leica Copy screw 
mount and have yet to see it with this camera either.

Gene

-------------- Original message from "Robert Lilley" 
<54moggie@embarqmail.com>: -------------- 


> 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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