Re: [photo-3d] ISO Duplex Super 120

[Brian Reynolds <reynolds@xxxxxxxxx>]

Ray Hannisian wrote:
> 120 film has 12 numbers which will align with the windows 
> in the camera back.  By using both positions, you will get 
> 24 stereo pairs.
> 

The paper backing on 120 roll film can have a lot of numbers.  There
are quite a few roll film formats (6x4.5, 6x6, 6x7, 6x8, 6x9, 6x12,
6x17) that all use the same roll film.  At least for Kodak films there
are numbers for 6x4.5 (16 exposures), 6x6 (12 exposures) and 6x9 (8
exposures).  I haven't used Fuji, Agfa or Ilford film.

>From the descriptions, I guess the ISO Duplex Super has two red
windows, one over the other along the length of the film.  Most roll
film cameras with more than one (usually two) red windows have the
windows across the width of the film so that you can read the
different format numbers.  In order to use the smaller format you
insert a mask before loading the film.

220 roll film does not have the paper backing that 120 has.  This
means that the film can be twice as long (extra film takes the place
of the paper on the spool), but you generally can't use 220 roll film
in cameras that use red window advance.  Cameras that have an
automatic advance (i.e., automatically stops at the next frame)
generally have an internal adjustment to switch from 120 to 220, or
require a special insert in the film back depending on the film type.

By the way, roll film formats are named based on their aspect ratio,
not the actual frame size.  In this way the frame size can vary a bit
between manufacturers, but the proportions remain the same.  For
example my Yashicamat (a 6x6 TLR) has a frame size of 56mm x 56mm.
The Fuji 690 (a 6x9 rangefinder, the Texas Leica) I rented a while ago
had a frame size of about 56mm x 84mm.

-- 
Brian Reynolds                  | "Dee Dee!  Don't touch that button!"
reynolds@xxxxxxxxx              | "Oooh!"
http://www.panix.com/~reynolds  |    -- Dexter and Dee Dee
NAR# 54438                      |       "Dexter's Laboratory"