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Roll Film, p.2

July 24, 2013


OK, you've decided what camera(s) you'll be using. First step after that decision is collecting backing paper and spools that fit the camera. You'll also need one whole strip of film — exposed or unexposed, it doesn't matter. You're using it to build a film cutting guide tool.

The second step is sitting down and making a map of your overlapping requirements. Each photographer will have his or her own. What size film will you be cutting? How many formats? What size darkroom do you have? Is the space permanent and dedicated, or temporary?

A permanent coating table, pre-set dead level, is a joy of convenience. My coating table is modular. I use a 24"x 48" folding table, topped with a 26"x 48" piece of thick plate glass. That part is permanent. I can use it to coat plates or LF film, basically when the whim takes me. When I coat roll film, I need 36"x 48". For me, it's best to temporarily line up five 36"x 10" thick glass sheets side by side. I can then use Grafix's 50 inches-wide roll of Wet Media Dura-lar.

You'll need the dimensions of your coating table before you make a cutting guide. The length of your cutting guide must be the same as the width of your coating table so that it can be clamped tight on the dried emulsion. It must have two straight, strong edges that will hold up to a sharp blade forever. Affordable is nice. Nielsen aluminum frame pieces are ideal on all counts.

The above picture represents a couple of steps. First, lay down strips of double-sided adhesive tape along the long edges on both sides of the film on the emulsion side. Carefully line up one of the Nielsen frame pieces right along one edge of the film. Press hard to make contact with the tape. Next, place the second frame piece one sixteenth of an inch/2 mm in from the second edge. Press to make contact. Now, cut strips of foamcore board to precisely, yet snuggly, fit between the frame pieces. It takes a stack of three, and each will be a little different in width. These keep the frame pieces separated and form a nice, sturdy assembly. Now, take a sharp utility knife and cut off the overhanging sixteenth-inch film selvage. You have made the cutting guide a little narrower than the film format because you'll pick up that width again when you cut your film.

Last step is to cover the foamcore board with a piece of gaffer tape (or duct tape, but I like 3M gaffer tape for a lot of tasks, including film holder repair, so I always have a roll). Mark the frame pieces on both ends of the film strip. If you are cutting more than one format — either because you have the cameras, or in order to maximize your cuttings — the silver marks make it much easier to determine under safelight whether or not you've got a long enough coating of emulsion.


Interesting stuff, backing paper. It has a lot going on. Take a minute soon to open a package of film you're willing to sacrifice. Since old, expired film from ebay is the easiest way for most people to get spools and backing paper in a hurry, you're likely to get the opportunity without wasting good film. Notice where the film is attached. Carefully remove it, but leave behind the piece of tape on the paper. If the tape is old and crusty, carefully remove it and mark the place. If you tear the backing paper, you can mend it with transparent tape on the white paper side of the roll.

In the picture above, you can see the dent in the paper about in the middle of the field of little horizontal arrows. That is where the film attaches to backing paper. It is the only attachment point. The arrows are there to tell you that you are coming up on the first exposure — if you are using a camera with a ruby window to see the backing paper numbers. Most older cameras have this system. After you know the take-up leader is secure in the take-up spool, you close the camera and advance the film until the number "1" shows in the ruby window.

The numbers on the outside of the backing paper are there for cameras with ruby windows, but they are very handy for us even when we use newer cameras that ratchet the film into place. More on that in the next section.

You can see that there are three lines of numbers in different spacings. Since this is 120 film, the top line is for cameras that expose 6x4.5 cm frames. The middle is 6x6, and the bottom is 6x9. The ruby window on any particular camera is located on the camera back so that the appropriate line of numbers shows through. With Kodak film, you can tell a new exposure number is coming up when you see the word "Kodak". Ilford film has four rows of circles that increase in size as you come up on the number. If you get in the habit of precisely centering the exposure numbers, you'll end up with even rebates, the clear space around each exposure.

The large, single vertical arrow is used with cameras that automatically ratchet the film into place after each exposure. When you are loading the film, you line up the arrow with red marks in the back of the open camera, then close the back and advance the film until it stops.

Cameras that don't fit the conventions have clever work-arounds that aren't necessarily obvious. A Beacon half-frame 127 camera has two ruby windows in back. You line up each number twice — first in the right side window, expose, and then in the left side window and expose again before repeating with each number. Sputnik stereo cameras have one window, but you advance the film in two's, i.e. "1", "3", "5", "7", "9", and "11" — twelve 6x6 cm exposures in six stereo sets.

This is as good a time as any to plead the wisdom of reading your camera's manual.

Below: The outside of a roll of Ilford paper, and the inside/film side of Kodak paper. Note the tapered leader/take-up tabs. This is what you stick in a slot in the film spool in order to catch the paper and film for take-up. The piece of tape is where film was attached, and will be again. With care, backing paper can be re-used indefinitely.

TIP: 120 paper is easy to come by. Most of the other formats, not so much. Spools are available on ebay. Also, a spool usually comes with a camera purchase. But, it can be a challenge to find enough original backing paper for "orphan" formats.

Happily, if you have just one original you can make as many copies as you need from 120 paper.

First, figure out which line of exposure numbers go with your camera (if it's a ruby window model). Punch a small hole through the middle of each number. Lay the backing paper on top of a stretched-out roll of 120 paper and mark through the holes. (Don't use a red pen.) Then cut the 120 paper down to size, making sure that both papers stay in alignment from start to finish. You may have to cut new tapered take-up tabs. Voila! New backing paper for your old camera.


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