Film Slitter for 120 Rollfilm
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Because of the limited number of
emulsions available commercially, slitting
film for the Minox camera has been a long
standing tradition. It is a small step to
slitting film for 120 or 220 roll film
cameras.
Kodak Infrared Film, now discontinued
in 4x5 format is not available in 120
format. In addition, Fuji Super HR is
available only in 16mm, UNsprocketed 35mm,
and 105mm. Aha! Two great films, slit,
spooled, and ready for 120 cameras.
120 film is approximately 61mm wide -
interestingly just a Minox width less than
the 70mm of the infrared film.
The same slitter block can be used to
slit film for 120 cameras, only the base
need be new.
If only 70mm film will be slit, a
narrower base may be made.
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If 105 mm film is (also) to be used, a
wider base can be made and the appropriate
slitter block guides manufactured.
In both cases, adding machine paper is
used over the film to prevent scratching
while slitting. The procedure is exactly
the same as used when slitting film
for Minox cameras.
If either film is sprocketed, the
slitting path can be altered to miss the
sprocket holes. In the case of the 70mm
infrared film, the space between the holes
is less than the standard 120 width. If
both sets of holes are removed, the film
is too narrow to load satisfactorily onto
a spiral reel for development. I have
chosen to leave a set of holes, and
mentally consider the lost image area when
visualizing the image with the camera. I
always spool the film with the remaining
sprocket holes in the same direction so I
know which part of the image is being
impacted when in the camera. One must
remember whether the lost area is at the
top, bottom, right or left of the image as
seen on the ground glass or with the
viewfinder.
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120 film is approximately 61mm wide and
830 mm long. A jig can be made to cut it
to length prior to slitting. Backing
papers and spools can either be saved or
usually obtained from a pro shop in your
area where they are usually discarded.
Since the combination is wound from the
loose (un-taped) end, and the film tends
to "crawl" as it is wound over an
increasing diameter on the spool, the
problem is to get the film taped to the
backing paper in exactly the right place.
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A trough exactly like the one used to
slit film, but the width of the backing
paper, helps to keep the paper and film
aligned during the winding process. I use
the insert from a Graflex Rollfilm Back as
a winder, positioned so, when the paper is
partially wound and ready for the
insertion of the film, the paper end is
1270 mm from the spool. If the paper is
wound tightly, the film may be "inserted",
pressed under the roller between the
already wound and the unwound paper. When
resumed, the winding of the paper draws
the film into the roll and allows the free
end to move in relation to the backing
paper. When the free end of the film is
about to "enter" the spool, a piece of
artists tape is attached to THE FILM (NOT ALSO TO THE
PAPER!), and as the sandwich is
drawn onto the roller a slight pressure is
maintained to attach the tape to the
backing paper AS IT IS
ROLLED ONTO THE ROLLER!. In this
manner the film will be flat against the
backing paper, and when pulled through the
camera, will advance properly with the
paper.
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