The exact dimensions of the rectangular 4x5' film area that gets exposed?

Yes, if absolute precision is needed, what he wants are pin-registered vacuum film holders. Linhof used to make them (or at least sold them with their name on them) they had a little battery powered vacuum pump. However, pin registration requires that 3 precision holes be punched into the film. Linhof also sold the punch to do that. Needless to say all that stuff was not cheap; on the other hand, if you could find them used, they probably would be cheap, who else would want them?

FWIW, my Graphic Riteway holders have a 96mm x 122mm opening, which is 5mm less than the nominal size of the 4x5 sheet of film.

Quote:

---

Originally Posted by graywolf

FWIW, my Graphic Riteway holders have a 96mm x 122mm opening, which is 5mm less than the nominal size of the 4x5 sheet of film.

---

The nominal size of the film is smaller than its stated size in inches. This was the glass plate size. The film was slightly smaller to allow it to be placed in a sheet metal insert to be used in glass plate holders.


Steve.

The important issue with regard to which item to place first in the stack... Fresnel, GG, and Grid... is whether the etched or focus side of the GG matches the depth of the film surface when it is in the holder. Anything which displaced the GG further away from the lens may result in a film plane in the holder being closer to the lens than the focus surface of the GG. That would put the shot out of focus when snapped, because the film would not match the distance that focus was viewed. That may also raise a question about the thickness of the Fresnel and whether it's thickness was accounted for in the distance of the GG from the lens, again relative to your film depth in the holder.

It's ultimately important that the GG focus surface distance from the lens is matched identically by the film plane depth of the holder if you catch my drift. In any event, it pays to check these surface distances if a Fresnel or a Grid sheet have been added to the camera. Most holders have a consistent depth from the holder outer surface to the film plane. Any time a GG or other masks, fresnels and such are added to the camera, one must make sure the focus surface (ground surface of the GG ends up in the corresponding position to the depth of the holder film plane that is going to replace it to make the shot.

Duh. Just measure a developed negative.

Quote:

---

Originally Posted by Pawlowski6132

Duh. Just measure a developed negative.

---

Or the aperture in the film holder.


Steve.

The film size according to ASA/ISO is 4" +/- 2/64th" by 5" +/- 2/64th". Regular films are about .007" and thin base is about .0045" thickness. Critical photographers who asked me in my Calumet days, I would customize the ground glass position for thick base, thin base, half way in between!

Since I was heavily involved with Calumet CC's and C1, all of the Cambos, Toyos, Galvins, and several others, it was always good business to tell our customers that you can never use a full 4x5 (because it isn't necessarily there to begin with), the film holders use a bit of the film, film hangers prevent full use of whatever film you have, finally I always wrote in magazines and/or the about 4 dozen different catalogs that I have produced that you don't want to try to use more than 3 3/4" x 4 3/4" and even that is chancy.

Lynn