120 film length

[Eric the Red]

Good evening!
I have a couple of older Kodak cameras, a #3 Brownie model B, and a 3a autographic folding pocket model C.
I have on order a couple of adapters to go from 122/124 to 120. Since the 120 film's back numbers will not show in the camera window, I would like to know how long a roll of 120 is entirely, so I can determine how many turns I need to wind so as to not overlap pictures.
Also, would I need to make a (I forget the correct name) "film gate/plate with a hole in it" for the narrower film to hold it flat?
Thank you for any help.
Eric

 

[BrianShaw]

Search for a thread of mine. I believe I discussed the number of turns on a Kodak 3A with 120 film. I also posted pictures of my film gate adaption.

 

[Sirius Glass]

As the film is wound, the spool diameter increases so the advancement amount decreases.

 

[wiltw]

I'm glad I keep a junk roll of 120 around for questions like this one! this based upon roll of Fuji color

• if start of full width of backing paper = 0mm
• film emulsion start occurs = 388mm
• film emulsion ends = 1223mm
• emulsion length = 835mm

Good luck trying to use 'how many turns' to reach next clear area with no backing paper numbers to guide you, since the thickness of the wound-up film changes the amount of linear advance with a single turn of the spool!

 

[Donald Qualls]

There are actually guides around for how much to reduce your count for successive frames, but the ones I've seen are for running 35 mm onto a 120 spool -- slightly thicker film, but no backing, overall result is probably that you'll wind up with expanding gaps between frames.

Best way I'd suggest is to make up a dummy roll using a second strip of backing in place of the film (you should easily be able to see the film start and end location on the full length backing) and wind it through the camera with the back open, marking the frame edge for each frame and counting turns to arrive at each position -- then carry the list of turn counts with you, so you can take the place of a turns-counting mechanical frame counter.

 

[BrianShaw]

That’s exactly how I did it, DonAld, except simplified and only used backing paper. Rather than fussing over trying to compute even spacing I just used the same number of turns per frame to ensure no overlap and accepted uneven spacing.

1906 Kodak 3A

The Kodak No. 3A Model B2, which I have adapted, was made between 1904 and 1906 as far as I could determine from the available literature. It was a "Pocket Folding Kodak" but pockets must have been very big back then because this one measures (in inches) about 10 x 4-3/4 x 2. The No. 3A was one...

www.photrio.com

 

[Donald Qualls]

Using backing only is "safe" in that it will have you advancing further than strictly needed. What I described is similar to the way I checked the advance on my Graflex 22 back after the first roll had spacing problems -- turned out I had the start mark a few millimeters too far when loading.

 

[Sirius Glass]

Take the backing from a 120 roll and write the numbers so the line up with the window of your camera. Then in the dark open a new roll of 120 film, remove it from the paper backing and tape it to the marked up paper backing. You will have to do that for every roll unless you find a brand that has the numbers were you need them.

 

[Donald Qualls]

The problem is that 116 has an edge window on film wider than 120. You have to block the window to avoid fogging the film with light going past the edge of the backing.

 

[BrianShaw]

... and returning to the specific question that was asked:

120 film - Wikipedia

en.wikipedia.org

 

[Eric the Red]

@BrianShaw and @wiltw, those are exactly what I needed! Thank you so much. I plan on doing just what @Donald Qualls suggested. On closer inspection, I have noticed that the front lens/glass is missing from the viewfinder. I don't know why I didn't catch that before I purchased the camera. So now a new hunt begins..... ha!
I appreciate everyone's help with my new purchase.
Brian, did you find that a tape film gate worked better than something made out of say, styrene (modelers plastic. Can be gotten in varying thicknesses and is easy to work with) or something else?

 

[BrianShaw]

The tape was not the actual film gate. I cut a thin, black, high-density cardboard for the actual film gate. The painters tape just held the cardboard in place. Styrene was my other option but I had none on hand.

 

[wiltw]

Take the backing from a 120 roll and write the numbers so the line up with the window of your camera. Then in the dark open a new roll of 120 film, remove it from the paper backing and tape it to the marked up paper backing. You will have to do that for every roll unless you find a brand that has the numbers were you need them.

And in this case you have the problem of locating where to put the leading edge of the film on the backing paper....finding 388mm from where the backing paper is no longer tapered at the lead end, while in total darkness.

 

[Sirius Glass]

And in this case you have the problem of locating where to put the leading edge of the film on the backing paper....finding 388mm from where the backing paper is no longer tapered at the lead end, while in total darkness.

In daylight locate the original location where the film was taped. Mark that location with your chosen method, then turn off the lights and tape the film to that location.

 

[Donald Qualls]

And in this case you have the problem of locating where to put the leading edge of the film on the backing paper....finding 388mm from where the backing paper is no longer tapered at the lead end, while in total darkness.

If you're reusing backing, it's usually pretty easy to locate where the tape strip was -- and in any case, you don't need to. You roll the tail onto the spool first, start the film when you come to the crease or hole that marks the tail end of the actual film, then roll together until you come to the head end of the film before taping it to the backing.

 

[Romanko]

"film gate/plate with a hole in it"

mask

What format are you planning to shoot? You can use a mask to shoot 6x9 cm frames or use the full length of the original frame which would give you 6 x 14 cm or 6 x 10.8 cm. In any case you would need a new viewfinder.

Did you consider using sheet film?

I'm looking forward to seeing photos taken with these cameras.