Back Focus Listings for 2 1/4 cameras ?

CameraQuest

CameraQuest

Head Bartender
Staff member
Local time
10:24 PM
Joined
Mar 1, 2005
Messages
6,602
anyone know of listing for the back focus of various 2 1/4 cameras?

ie the distance between the lens and the film plane?

useful for determining what lenses can be adapted to what cameras,
among other things

Thanks,
Stephen
 
Even with knowing the register I find it really hard to measure that distance on the camera, maybe some one here has a good method.
 
charjohncarter said:
Even with knowing the register I find it really hard to measure that distance on the camera, maybe some one here has a good method.
Click to expand...

It depends somewhat on the camera, you need to have a clear vertical drop from the flange to the film plane. I use a dial readout caliper with the base sitting on the flange rim and the depth measuring tail reaching down into the camera body. If I don't have that clear shot from the flange itself, I have a little bar of flat, 4mm thick glass that I lay across the lens mount flange that I can use as the base reference for the measurement, and use the same dial readout caliper from that.

A piece of glass up against the film rails provides the focal plane reference point to measure to. Or the pressure plate, if you know how far behind the film plane the pressure plate is supposed to be (usually .001-.003 inch).

G
 
You must log in or register to reply here.
Back
Top Bottom