Re: Dealing with reloading in daylight

[Edward Meyers <aghalide@xxxxxxxxx>]

On Fri, 25 Jul 1997, Wayde Allen wrote:

> 
> On Thu, 24 Jul 1997 ANDPPH@xxxxxxxxxxxxxxxxxx wrote:
> 
> > But it turns out that this is a minor problem. The major one seems to be
> > a leak probably through the felt which does not go through the film
> > leader but rather leaks past it at the top and bottom of the cassette
> > and reaches the IR film located towards the core of the spool. The film
> > leader does not provide a "tight" seal against the plastic top and
> > bottom spool flanges. I just measured the distance on one spool and
> > found it to be about 35.6 mm ... I also found that 35mm film measured
> > 34.8 mm. If this is prevalent then the .8 mm gap may be sufficient to
> > allow some light (actually IR if the felt trap is not totally IR proof)
> > to leak in towards the core of the cassette. 
> 
> I have heard about film cartridges made with feltless light traps.  I
> think the manufacturer may have been Leica, but am not sure.  As far as I
> know these are also no longer made, but they might be available on the
> used market.  I'm wondering, since we are talking about reloading
> cartidges anyway, if using one of these cartridges with an opaque leader
> would be an improvement?
> 
> Does anyone know about this kind of cartridge?  Are they still available,
> and if so from where?
> 
> - Wayde
> 
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Yes, I do have a number of the Leitz reloadable cartridges.
However, it is the action of the bottom camera locking key
on the Leica cameras that also turns the part of the cartridge
to cause the "door" to open. When the key is turned to remove
the camera bottom, the same action also  causes the
light-tight cover to go back into position.
Nikons and Canons at one time also had this type of locking
key and also supplied cartridges similar to the Leitz ones.
All at available in the used market. I have Leicas so that
I can use them (screw-mount leicas accepted cartridges
that do not fit the M Leicas...beware). Zeiss (real) Contax
cameras also had similar film cartridges.
Ed Meyers

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