Saturday, September 16, 2017

How to cut 120 film down to 127 size by James Tappin

[Editor's note: I'm delighted to present 127 Film Photography's first article, authored by James Tappin.

Many thanks to James for sharing his expertise!]

This is a method that I have used successfully (and also destroyed some films).

You will need:

  1. A roll of 120 film
  2. A 127 spool
  3. A second 120 spool
  4. A changing bag (or a darkroom)
  5. A large cigar cutter (80 ring gauge -- this is the only readily available size that will fit over a 120 flange).
  6. An accurate vernier caliper
  7. Scissors
  8. Convenient length gauges for the length trims (I use 3 pieces of acrylic "glass" because I had some left over from something else)
  9. A marker with good contrast to the backing paper

If available a 120 film back from a medium format system SLR is handy but not needed.

Step 1:
Either by hand in the changing bag or darkroom, or using the 120 back, spool the film onto the spare 120 spool, so it is now in the “exposed” direction.

Steps 2 through 6 can be done in daylight.

Step 2:
Cut off the excess on the trailer. From the tip of the 120 tab, I usually cut 220mm (for "standard" length 127 film you should cut 290mm; in theory it might be possible to get away with as little as 80mm).

Step 3:
With the vernier caliper measure and mark 46.5mm from one side. The flanges of the 127 spool are 47.2mm apart, but anything more than 46.5 and it's likely to be impossible to get it to fit in smoothly. Do NOT try to use another 127 backing paper as a guide; it's just not accurate enough.

Step 4:
Slip the cigar cutter over the end of the film and very carefully score around at the 46.5mm mark. Only cut through 1 or 2 layers at this stage.

Step 5:
Cut a tail on the paper so that it will fit into the 127 spool.

Step 6:
Make sure the film, the 127 spool, the cigar cutter, the scissors, and the measure for trimming the back end of the film itself are all in the changing bag.

Steps 7 through 15 must be done in a changing bag or complete darkness.

Step 7:
Very carefully replace the cutter on the film roll, and align it with the initial cut.

Step 8:
Gently but firmly squeeze the cutter and rotate the film spool such that the drag tightens the film on the spool. Continue until the short end of the spool comes right off.

Step 9:
Fit the end of the backing paper into the 127 spool and start to roll it onto it, feeling for the film itself (it won't be far).

Step 10:
Cut off the excess length from the film. For 220mm off the backing paper, I cut 95mm off the film; for standard 127 cut 165 mm off.

Step 11:
Continue to roll paper and film onto the 127 roll (put a little slack into the paper at this point as the 127 roll is more tightly wound). If you find the edges crinkling and snagging on the flanges at this stage -- chuck it and try another roll, and cut it a bit narrower next time!

Step 12:
When you get to the start point of the film you may find there is a small excess of film or paper. In this case carefully unstick the tape, and re-stick it where the lengths match.

Step 13:
Draw a line across the backing paper where the film starts (or a little bit after).

Step 14:
Finish rolling the leader onto the spool.

Step 15:
Carefully holding the roll so it doesn't come undone extract it from the changing bag.

Step 16 can be done in daylight.

Step 16:
Cut 150mm off the leader, and make a tab to fit the 127 spool (taking care not to let the roll come loose).

I recommend putting it straight into the camera at this stage as (a) there's no tape to keep it done up and (b) the edges may not fit as close to the spool flanges as machine-made films.

Note that this method is only really suitable for cameras like the Yashica 44 (and possibly some baby Rolleiflexes) that use the red window to align frame 1, and then have an internal mechanism thereafter.

To align the film for frame 1 (Yashica 44):

  • wind on until your marker is seen
  • reset the counter
  • wind on 1 frame
  • reset the counter again.
With the measurements that I use you should get 15 frames on a 4x4.

For a more automatic counter you will need to determine how far the start mark should be from the film start and make a mark there instead of at the film start. I'm not sure how you could do it for a camera that relies on the red window for advancing other than using a "new" backing paper with 127 numbers, which adds a whole new alignment problem.

I recommend trying this with cheap film first, as it's quite easy to destroy a roll. So far I've only used cheap expired film. Unfortunately the cheapest major brand currently available in 120 size, Fomapan, has black backing paper which would make marking the start much harder (maybe a sticky label would work?). [Editor’s note: Or perhaps a silver gel pen?].

Also: Cigar cutters are VERY sharp, mind your fingers!

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