Re: [APML] tech pan revisited

[Jerry Lodriguss <jerry@astropix.com>]

>  Scott's somewhat puzzling image is here:
>http://www.creatorsview.com/pages/demo.html


Hi John,

Thanks for the link.

I was wrong about having seen lines like this before from scratches from 
dirt in the felt light trap.

The lines appear to be dark lines of density in the negative image.  They 
are not scratches where the emulsion was removed which would make dark 
lines in the positive image.

This implies a light source.

They are pretty straight but don't always run parallel.  They are not 
static electricity, which would look like lightning.

It certainly doesn't look like the emulsion cracking.

It doesn't look like any kind of moisture during exposure, or development 
problem.

The predominant lines are light in the positive image, but there are also 
dark lines on each side of a light one. The dark lines seem more diffuse.

In one case (4th line from the left), a single light line at the bottom 
forks into two lines at the middle of the frame. The 5th line from the 
right does the opposite.

This is just a crazy mystery!

Jerry







Photoshop for Astrophotographers - http://www.astropix.com/PFA/PFA.HTM











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