DIY 9.5mm film stock with circular central perforation. It works! I think

[Iain Petrie]

Years ago I bought a DIY hand crank music box (search online or see here on Amazon, though you can get them far cheaper if you search around). They come with a tiny punch which makes holes in the paper strips so you can make your own tunes:



My wife asked if this could be used to perforate 9.5mm film and I smiled and explained that no it couldn't because 9.5mm film has rectangular sprocket holes of a very specific shape and size, whereas this makes a round hole. Then I realised the punch is roughly the right width so maybe it would work. I cut down some old strips of 16mm double perf, just roughly measured by eye:



then punched holes in the film, again just measuring roughly using the lines on the pad as a guide:



The punch did the job:



And the result looked lovely:



But could it possibly work in a camera? Yes! It turns out you CAN get a square peg in a round hole (or at least, a rectangular peg in a round hole)

I tried it in 3 different models, a c1923 hand cranked Pathe Baby, a c1933 motor driven Cine Nizo Model F, and a 1959 Prince. It worked perfectly in all three. And it also worked with the single shot function in the Prince.

Here's the video showing the 3 cameras, 2 clips repeated for clarity, and the single shot function at the end.

Any thoughts on this before I try this with unexposed colour stock??

I'm hoping the claw is catching the film consistently in the same place between the sprocket hole each time, and that it's roughly central to the hole so the frame isn't shifted up or down. Maybe this wouldn't work in a projector, but at the moment I just want to be able to use these wonderful old cameras with colour film, and I can telecine the results. The sprocket hole will 'eat into' the frame at the top and bottom a little but hopefully not too much.

The next job is to automate the process a little more; at one punch every 5 seconds, I won't be going into commercial production any time soon...

The video:

[Simon Wyss]

Why not. You could grind two flats on the punch on opposite sides but the die would need to have the same shape which is a bit a bigger job.

[Iain Petrie]

I thought about that Simon, but sadly I lack even the most basic engineering skills!
I'll keep it simple to start with and see what the results are like. I already started on the "machine" to wind the film through to cut and perforate the film with the punch in the dark, and it's made out of Lego, which is a great material to work with for simple people like me . I have Ektachrome 16mm film and a large reel of Kodak 320T 16mm so the next job is to get a C41 and an E6 kit and learn how to develop colour film.

[Simon Wyss]

Wish you success, just for fun

I had or have still the project to build a slitter and a perforator for the 9½ format because the people of the French Ninefive club deem it unworthy to even think of converting a black-and-white stock on their apparatus. We have talked about that earlier on this forum, Dominique De Bast, me, and others. Supposed I had such equipment, what and how much of it would you take? If I have counted well, you ought to be in possession of two 9½ cameras.

[Dominique De Bast]

The trouble with 9.5 black and white filmstock is the lack of possibilty to have it process properly. There was a demand (modest, let's remain realistic) for such film but; if I may reminde that, the Spanish lab that first agreed to made a little transformation to one of their machine to offer a professional service at afordable price failed to do so. Now that Ektachrome is available again, I presume black and white could "compete" only of the difference with the cost of colour film is high. I published an article about different filmstocks available in the latest copy of the French magazine, it will be interesting to see what the feedbacks will be (so far, two people reacted).

[Iain Petrie]

I now have 5 working 9.5 cameras and one more on the way . Regarding film stock: I've probably used only 200 feet of the 3000 feet of B&W film I bought in November so I don't have an urgent need for more B&W film for quite some time! My current modest experiments with slitting and perforating are because I would love to shoot with colour film again. I expect learning to bucket develop with C41 and E6 chemistry will be quite a challenge though...

[Janice Glesser]

I just love the idea of you using a music box hole punch for your 9.5 sprocket holes! Truly a DIY solution! You are very resourceful Iain I am sure you will figure out a way to do color film.

[Iain Petrie]

Thanks Janice! Update:
Slitting 16mm down to 9.5mm: total success, using a USSR 8mm slitter. It cuts 16mm in half for Standard 8 but by taking the top off and adding a cut down match stick, 1.5mm wide, it cuts one side to a perfect 9.5.
Perforating: almost there. With no engineering skills, using only clamps, superglue and tape, it's turned out to be a lot more complicated than I expected. Even if the hole spacing is only 1/10th mm out, after 10 holes you are a mm out of course.
Colour developing: v poor results so far but it can't be that hard! I'm finally getting the temp up to the required consistent 38 degrees but the negatives are still very thin and very blue. It could be the film . I read that the Vision 3 movie film has basically no shelf life (mine is long expired) and should be developed in EN-2 chemistry but I'm using C-41, and lately, RA-4, which are suboptimal at best, I read.

The perforator is a thing of beauty at least ;-)