Film camera question

"Luis Ortega" wrote in message
...
Thanks to all. I need to check out the various suggestion
offered. To clarify, the defect is not an undevelopment
effect caused by the rails of the reels impeding the
developer along the sprocket hole areas but something
that is happening only inside the negative frame itself.
It is very evident on a contact sheet when you can see all
of the frames side by side. Each contact frame appears a
little whiter and more washed out along one edge, usually
the bottom edge but sometimes the side edge.
I work in a school and see dozens of cameras in the
darkroom so I can't do a lot more than try to follow it up
as it happens, but I am curious as to why this is
happening.
Thanks to all.

If the effect is inside the frame its obviously happening
in the camera. Since it seems to happen on different edges
in various pictures its not likely the shutter. It _might_
be an internal reflection of some sort. The way to find out
is to put a small piece of ground glass in the film gate,
open the shutter (T exposure) and shine a flashlight intot
the lens from different angles. Actually you may be able to
see a reflection just by eye. The cure is to paint whatever
is causing the reflection with flat black paint or some
other light absorptive material.
It is possible for a focal plane shutter to cause a band
of under or overexposure at one end of its travel but it
will consistently at the same place on each frame. It is
also possible for a focal plane shutter to cause spots or
steaks on frames if it has holes in it, but this sounds like
something that is not shutter related.
If the camera is an SLR check for light leaks from the
finder when the mirror is in the up position. Sometimes the
light seals in SLR's get old and don't work. Unless you eye
is pressed right against the finder some light can get in
and cause some form of fogging. I am suggesting this only
because your problem seems to be a little unusual and the
cause may be a bit unusual.


--
---
Richard Knoppow
Los Angeles, CA, USA

If the stripe is uneven and outside the frame, Nick Lindan's
explanation is dead on target! Unfixed (not cleared by the fixer)

Since we're talking in school
I wonder about just the simple problem of
a bad fix job.

Collin
KC8TKA

David Nebenzahl wrote:
Nicholas O. Lindan spake thus:
"Luis Ortega" wrote

something that is happening only inside the negative frame itself.

If this is 35mm, something everyone seems to be assuming,
I'll toss my hat in with the sticky-vertical-shutter crowd.
Vertical shutters were used on Exa's and Exakta 500s -- if there is
one of these hanging around I'd bet money it's the one with the problem.

Oh, come on, Nicholas: how likely do you think it is that students would
be using these antiquated cameras?

FWIW, a vast number (maybe a majority) of 35mm SLRs from the 80s
and 90s use vertical travel focal plane shutters. Not just AF,
but many MF as well. The Nikon FM and FE are two common ones.
Most of the SLRs with 1/125 or faster flash sync have vertical travel
shutters.

On Tue, 23 May 2006 18:53:16 GMT, "Luis Ortega"
wrote:

I work in a school and see dozens of cameras in the darkroom so I can't do a
lot more than try to follow it up as it happens, but I am curious as to why
this is happening.
Thanks to all.

Sounds to me like shutter bounce in a camera with a vertically
traveling shutter such as an FE, FM2, F3 and many others.
Manufacturers such as Nikon switched to vertical travel in an effort
to increase the flash sync speed, top shutter speed and for other
reasons I'm sure.

==
John S. Douglas
Photographer & Webmaster
www.legacy-photo,com
www.xs750.net

On Tue, 23 May 2006 22:59:26 GMT, "Richard Knoppow"
wrote:

If the effect is inside the frame its obviously happening
in the camera. Since it seems to happen on different edges
in various pictures its not likely the shutter. It _might_
be an internal reflection of some sort.

Interesting thought. Perhaps a shiny edge on the mirror holder ?

==
John S. Douglas
Photographer & Webmaster
www.legacy-photo,com
www.xs750.net