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Re: What Is It
- To: Tom Droege <email@example.com>
- Subject: Re: What Is It
- From: Chris Albertson <firstname.lastname@example.org>
- Date: Sun, 11 Oct 1998 21:10:23 -0700
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Tom Droege wrote:
> So what are the spots?
Here's my guess and it's just that Assuming that 1) the spots stay put
even when you rotate or move the camera relative to it's surrounding
between exposures and 2) you do not have the camera coupled to a microscope.
(sure looks like you do) then my guess is a manufacturing defect like a
scrape on the surface or on one of the layers below the surface. The
spots are three to five pixels wide and not aligned in either x or y.
Even the two that look like they may be are rotated a few pixels off
vertical. They are also brighter along the centerline and darker then
the surrounding background in outline. To me the origin looks more analog
then digital. I would think a trap defect would be aligned with the
shift direction perfectly.
Are you sure you have not built a pin hole camera?
I've seen "artists" intentionally make pinhole cameras with the film plane
at grazing angles to the "optical axes" It turns points into lines but
unlike a lens camera everything stays in focus.
A light leak could explain the sigmas you got that grow faster than
sqrt(mean). I've found when I try to make a room dark for photographic
work that it is really hard. I need to use three methods where each should
have been enough in itself.
Do you think it is light tight? Get a 500W halogen work light or maybe two
and place them a foot or so from the camera. See if the mean count goes up.
--Chris Albertson home: firstname.lastname@example.org
Redondo Beach, California work: email@example.com