plate holders

What I do know for sure is that I use modern film in modern film
holders in cameras that were originally intended for glass plates. In
each one the ground glass has needed to be shimmed out .060inch for the
film and grounglass to match up.
That's why many old plate holders have film inserts in them, its not
just to"hold" film, it also moves the film forward in the holder to the
positon once occupied by the surface of the glass plate.
Another trick people sometimes use is to install the groundglass in the
camera with the ground side out, thus moving the focus plane out (the
thickness of the glass) so it matches up to modern holders.
Building a plate holder from scratch may allow for something different,
my point had been to address the idea of different thickness in holders
is for a reason.
Robert Newcomb

        
On Jul 6, 2004, at 4:24 PM, jack reisland wrote:

> This reasoning does not seem logical. If the tin plate holder is
> properly
> constructed, the front surface of the tin plate will be exactly in line
> with the original film plane. The thickness of the plate has nothing
> to do
> with it, since the extra thickness extends backward from the film
> plane,
> not forward somehow into the camera. If all other sources fail, the
> instructions for making plate holders in t he book "Primitive
> Photography"
> could be modified to make a rather crude but serviceable single sided
> plate
> holder.
>
> Jack Reisland
>
> Robert Newcomb wrote:
>
>> Glass plates are about 1/16th (.060) thick, film is about .005 thick.
>> So if you put a glass plate in a standard spring back, the emulsion
>> will be too far forward (closer to the lens) as compared to the
>> groundglass focus screen. You can have an 8x10 glass plate holder
>> made, but you would also need to have a new grounglass panel made as
>> well so the focus planes match up.
>> From what I've seen, wet plate holders were a good bit thicker then
>> dry
>> plate holders or film holders. That may be what the Star company
>> person is saying, a wet plate holder would be too thick and a double
>> sided would be way too thick even to physically fit in a standard
>> spring back.
>> It can be done though, you just need a holder and a back.
>> Robert Newcomb
>> On Jul 6, 2004, at 3:17 PM, Gregory Popovitch wrote:
>>
>
Received on Tue Jul 6 15:06:41 2004