Help w/film holder dimensions
 

In the continuing saga of rebuilding my ROC Universal camera, I've
determined that what I have is *definitely* not a 5x7 camera (it appears
to be a 5x8). Since I want to actually use it with standard-size film, I
need to adapt it. To that end I acquired a bunch of old 5x7 film holders
in a lot of 8 holders in pieces-n-parts from Pacific Rim Camera (what
the guy I've been emailing there called a "box-o-fun"). Looks like I'll
be able to get 3 good holders out of the bunch; not bad for about $20.

These are "modern" (i.e., standard ANSI) holders, not the antique ones
made for the camera. (I've given up on finding the actual ROC holders
for the time being.) So what I'm going to do is to build a new back to
take the standard 5x7 holders. I think this is just doable with my
woodworking skills.

In measuring the holders I have, some questions arise. I found a web
page that purports to give specifications of standard film holders
(http://home.earthlink.net/~eahoo/page8/filmhold.html). In comparing
three of my holders to the chart there, everything more or less
jibes--certainly within close enough tolerances for my purposes--except
for one thing: the height of the exposure window (given as "exposure
height" in the chart).

For a standard 5x7 holder, they give this dimension as 7.010. But on all
of mine this opening measures almost exactly 6-3/4". Why this discrepancy?

The holders I have are wooden ones sold by Kodak; one of them says it's
made by Folmer for Kodak. They all agree with each other, more or less,
to 1/32".

I'm actually not sweating this too much: I figure I'll make the back to
the maximum dimensions so that it'll take all the holders I have. (And
of course I know that the one crucial dimension is the depth to the film
surface, which I'll attempt to get as close as possible.)

So does anyone out there have a link to a reliable source of film holder
information--or maybe even a real paper book that they could copy this
info out of?


--
Found--the gene that causes belief in genetic determinism

Help w/film holder dimensions
 

David Nebenzahl wrote:

So does anyone out there have a link to a reliable source of film holder
information--or maybe even a real paper book that they could copy this
info out of?

David, this is the best information I've found to date. I cannot find
the original ANSI document anywhere.

http://home.earthlink.net/~eahoo/page8/filmhold.html

Help w/film holder dimensions
 

(which meant you found the same I have)

It's an affirmation.

Help w/film holder dimensions
 

On 5/16/2009 12:08 PM John J spake thus:

David Nebenzahl wrote:

So does anyone out there have a link to a reliable source of film holder
information--or maybe even a real paper book that they could copy this
info out of?

David, this is the best information I've found to date. I cannot find
the original ANSI document anywhere.

http://home.earthlink.net/~eahoo/page8/filmhold.html

That's the same page I gave a link to. (He has a link--an incorrect one
that needs to be trimmed back to work--to the ANSI site with the
standards documents, but the information isn't free.)

I wrote the person who put that page up, and received a very quick reply:

A lot of the standards are just that-just manufacturing
guidlines-there were so many differant manufacturers that a lot of
them just made holders to fit their own cameras to eliminate
competition-just design your camera around the holders you have-Good
luck on your project!

Not exactly the response I was hoping for. I mean, if there are
standards, doesn't that mean that manufacturers are 'spozed to follow them?

In any case, since the discrepancy is in the exposure opening, I can
simply make the opening the size given in the specification, which is
larger than my holders' openings; no harm, no foul. That way, if I ever
do get other holders that follow the spec, they'll work too.


--
Found--the gene that causes belief in genetic determinism

Help w/film holder dimensions
 

David Nebenzahl wrote:
On 5/16/2009 12:08 PM John J spake thus:

David Nebenzahl wrote:

So does anyone out there have a link to a reliable source of film
holder information--or maybe even a real paper book that they could
copy this info out of?

David, this is the best information I've found to date. I cannot find
the original ANSI document anywhere.

http://home.earthlink.net/~eahoo/page8/filmhold.html

That's the same page I gave a link to. (He has a link--an incorrect one
that needs to be trimmed back to work--to the ANSI site with the
standards documents, but the information isn't free.)

I thought I'd get you little present for your effort so I bought a copy.
Guess what - it's just the title page. Worthless. I'll put it up on a
site if you like..

I wrote the person who put that page up, and received a very quick reply:

A lot of the standards are just that-just manufacturing
guidlines-there were so many differant manufacturers that a lot of
them just made holders to fit their own cameras to eliminate
competition-just design your camera around the holders you have-Good
luck on your project!

I do not believe him. I've used many different view cameras and holders
without problems. Heck, lately I've been shooting a big-iron Kodak 8x10
with a 375mm lens _wide open_ at 20' without focusing errors.

Not exactly the response I was hoping for. I mean, if there are
standards, doesn't that mean that manufacturers are 'spozed to follow them?

Yup. Not too many camera makers manufactured their own film holders, and
nobody wanted the liabilities of dimensional differences.

In any case, since the discrepancy is in the exposure opening, I can
simply make the opening the size given in the specification, which is
larger than my holders' openings; no harm, no foul. That way, if I ever
do get other holders that follow the spec, they'll work too.

Meanwhile, I'll look around here. I might have a standard 5x7 back.

Help w/film holder dimensions
 

Here's that ANSI document.

http://www.digoliardi.net/bs.gif

pitiful

Help w/film holder dimensions
 

On 5/16/2009 1:39 PM John J spake thus:

Here's that ANSI document.

http://www.digoliardi.net/bs.gif

pitiful

Did you pay for that? We should take up a collection for you (either to
reimburse you or to hire a good lawyer to sue them!).


--
Found--the gene that causes belief in genetic determinism

Help w/film holder dimensions
 

David Nebenzahl wrote:
On 5/16/2009 1:39 PM John J spake thus:

Here's that ANSI document.

http://www.digoliardi.net/bs.gif

pitiful

Did you pay for that? We should take up a collection for you (either to
reimburse you or to hire a good lawyer to sue them!).

It cost not more than a couple beers, and it was less filling.