Producing 828 backing paper from 120 backing paper
The backing paper for using with a 828 spool and 35mm film can be cut down from 120 backing paper. 828 backing paper is smaller both in width and length. The dimensions for different makes of backing paper varies slightly. Try and choose a 120 backing paper that has light annotation. Examples of this type of paper are Kodak Portra and Ilford FP4 Plus.
Nominal Values are:-
- 120 Backing Paper:-
Width: 62mm; Length 1430mm
- 828 Backing Paper:-
Width 35mm; Length 810mm
At each end of the 828 paper there is a tab and taper. The tab is 12mm wide x 10mm long. The taper covers another 20mm. These are included in the overall dimensions above. Now cut the 120 paper to 828 size. Accuracy is important because if the backing is too narrow your images are prone to light leaks through the side, if the paper is too wide then it won't roll properly on to the spool. Use a straight edge and a hobby knife/scalpel. Roll the backing paper neatly onto a 828 spool to check the dimensions of the new backing paper. Adjust if necessary.
After cutting the 120 paper to size, you need to annotate the paper with guidelines for where the film attaches and the numbers that are seen through the red window.
Measuring from the start end of the paper make the following marks using something like a Sharpie or some other quick drying permanent marker. Do not use Biro as it takes too long to dry. If the ink is not perfectly dry it will transfer to the film when rolled.
- At 21cm from the leading end tab, draw a line across the backing and annotate it 'Start'. This is where the film is attached to the backing paper.
- At 6cm from the start line, make a small mark to indicate the position of the Number '1' of the 8 exposure record on the backing.
- Now Annotate the first exposure number. Check the position of the red window of the cameras you will be using. The most popular is the centre (17.5mm). You only need to annotate what is required. If your backing paper has dark lettering, you may want to use 'A', 'B', 'C' etc. to distinguish between the 120 markings and your new markings. Cross out the old markings. Put some markers (dots, crosses, squares,) before the number as a taletale that the number is about to appear. Do not use tipp-ex, or the like, to obliterate the old marks. It will peel off and ruin your exposures.
- Now continue with the rest of the numbers. The distance between the 8 exposure numbers is 43mm.
- Make a mark 6cm past the number 8 of the record and draw a line across the paper. Annotate this as 'End'. This is where the free end of the film finishes.
- On the start taper write 'Un-Exposed' and on the finish taper write 'Exposed'
Measure the distance between 'Start' line and the 'End' line. This is the length of film required. It will be about 42cm. Roll the backing paper neatly onto an 828 spool. Run the backing paper through the camera to check the position of the annotation.