Re: [APML] tech pan revisited

[Chuck Vaughn <aa6g@aa6g.org>]

Scott,

I'll be willing to bet you have a moisture problem. Are you purging the 
camera (and if so where are you introducing the nitrogen) and is the 
camera covered with a plastic bag to keep the outside air from 
overpowering the purge? Also how long after exposure are you developing 
the film? And if not immediately how is the camera stored until film 
development?

I think Jim uses a high vacuum on the film and that makes it VERY 
sensitive to moisture. If your environment is is not 100% dew free all 
night long then high vacuum hypered TP will require careful measures to 
prevent moisture problems.

Chuck <aa6g@aa6g.org>

---------------------------------

> For those interested parties, I finally had a chance to work on the 
> tech
> pan issues that plagued me from the beginning of this year.
>
> As a reminder I was having problems with vertical lines running up and
> down the exposed frame, an example is posted at the bottom of page
> linked below. The top image has been quickly processed, the other 2 are
> raw scans.
>
> My tech pan was hypered by Jim Janusz and has been kept in the freezer
> in zip locked baggies with desiccant since arriving from Jim.
>
> I only took 2 frames on Monday night to avoid having those 2 frames get
> rolled up on the camera spool after exposure. That was the only thing I
> could pinpoint from my attempts in January causing the vertical lines.
> As can be seen from the 2 images on the page, no vertical lines,
> however, on part of the developed strip those lines showed up again.
> They were on the part that was wound up on the camera spool.
> http://www.creatorsview.com/pages/demo.html
>
>
> It is bizarre, no other film does this in this camera. I have used 
> E200,
> RG200 hypered, and Supra 400 all in the last week and nothing of the
> sort happened. Here is a link to a Supra 400 shot from last week.
> http://www.creatorsview.com/pages/display.html It still needs work but
> you get the idea.
>
> I'm still not sure what is causing the problem, but for now, I can 
> shoot
> 2 frames before having to take the film inside for developing. While 
> not
> a bad thing to see your results immediately, I'd like to be able to 
> keep
> shooting when the sky is clear. At least now I know what not to do.
>
> Confused in B&W,
>
> Scott Hammonds 

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