Re: [APML] Pentax 67 purge port........NOT!<g>

["Bobby Middleton" <bobm@koyote.com>]

----- Original Message -----
From: Tim Povlick <potentate@home.com>

>
> I was curious about purging so here goes some questions:
>
> When one drills either the 67 or 67-II, for daylight use
> would you have to plug the hole else light will get in?

Mine will have a bit of a leak. A small piece of electrical tape is a fix
for me.......if I remember it   :-o

>
> In a desert environment, say  15% humidity is a purge
> system necessary for hypered film?

Probably not necessary at all for 35mm, but the size of the 6x7 neg makes
flatness a real issue and moisture is an enemy of flatness. I would bet the
desert rats will tell you it's necessary. It's definately necessary in east
TX.
>
> If you have some accessory before the camera, say a
> field flattner that can be drilled, is this an acceptable
> place to drill?
>

By all means if you have something in front of the camera I'd use that to
port in the N2.

> Since oxygen (as well as H2O) seems to be the enemy
> of hypered film, it would seem a nitrogen purge is better
> than a dried air purge.

N2 is very easy. And cheap after initial setup. I'd rather use that with
just a bleed flow instead of messing with a dessicant and air moving system.
Bobby Middleton



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