Cheapskate Life - Modifying roll film holders/backs

[fdonadio]

Dear fellows,


In my eternal quest to save cents, I ask myself another question.

First, a little bit of background: I’m planning on building a panoramic camera that can be used handheld and uses 120 film. 6x12 feels good enough.

I have looked into these options for modifications:

1. Holga Pan body: film flatness is a problem, body is flimsy and may flex if using a heavier lens.

2. Kodak Autographic No. 1A: not so much better than the Holga, added to the fact its design for 70mm film.

Now I am contemplating building the camera around a 6x12 back. This would solve the aforementioned issues. Could be a DaYi- or a Graflex-style holder. But prices are only getting higher!

Then I saw that 6x6 and 6x7 Graflex-style holders are much more affordable and asked myself: are these backs completely different from the 6x12 ones, or are they the same, just with a different format mask? If they are the same, it would be a simple matter of “opening the gate”, right?

So, has anyone looked into this?


Cheers!

 

[koraks]

It's been a while since I sold my last 6x7 back but I'm pretty sure that you could not modify it to 6x12. Depending on the construction of the back you may be able to widen the gate a little, but the flat section and the pressure plate are generally only slightly larger than the actual recording format. So this is a no-go, I'm afraid.

The idea to build a box around something like a DaYi back is probably your best budget bet.

 

[Dan Fromm]

Then I saw that 6x6 and 6x7 Graflex-style holders are much more affordable and asked myself: are these backs completely different from the 6x12 ones, or are they the same, just with a different format mask? If they are the same, it would be a simple matter of “opening the gate”, right?

Um, I just looked at my RH-12. The film carriage's pressure plate is ~ 3 inches long, the distance between the rollers (center to center) is ~ 3 1/4 inches. No go.

 

[Donald Qualls]

it would be a simple matter of “opening the gate”, right?

Well, you'd also have to modify the frame counting system in some way. For a 6x6, assuming you stretch the frame enough to accommodate 6x12, I guess you could advance twice for each frame.

But you would have to stretch the frame, extend the pressure plate, expand the shell -- because there is no way you have 6x12 space in a Graflex (at least) 22 or RH12 roll film holder.

I have seen a couple 3D printable 6x12 backs that fit 4x5 Graflok mount...

 

[BrianShaw]

One of the concerns with just widening the gates on a roll holder is that the amount of film passed over the gate when it is rolled won’t change, so I’d expect overlapping frames.

Have you seen my post from a few years ago on converting a Kodak 3A (122) to roll film? Others have done similar. Im still wanting to refine the film plane/gate by using better materials and contemplating a red window option, but it worked and I wasn’t disappointed with the Rapid Rectilinear performance. Those cameras can be a cheapskates wet dream. I know…

 

[fdonadio]

Um, I just looked at my RH-12. The film carriage's pressure plate is ~ 3 inches long, the distance between the rollers (center to center) is ~ 3 1/4 inches. No go.

Thanks for the work and confirmation.

Maybe the RH-12 and RH-10 are the same, only with a different advance mechanism. RH-8 is probably different (bigger) but doesn’t look modifiable either.

I thought too much about this and didn’t see the clear fact that Graflex backs are limited to 6x9 (2x3”). I was hoping I could save a lot by modifying an RH-12 or RH-10, but now it seems clear I was hoping too much.

So, my only choices are now a DaYi (and other Chinese lookalikes) or a Horseman ($$$).

There are 3D-printable cameras, but printing using good (stable, resistant and good looking) materials costs as much as buying one of these backs.

I think I should stop being a cheapskate, haha!

 

[fdonadio]

But you would have to stretch the frame, extend the pressure plate, expand the shell -- because there is no way you have 6x12 space in a Graflex (at least) 22 or RH12 roll film holder.

I have seen a couple 3D printable 6x12 backs that fit 4x5 Graflok mount...

Yes, I knew about all the modifications needed. It’s a lot of work indeed. Expanding the shell is not an option. For some reason, I thought maybe I wouldn’t need to do that.

I’ve seen lots of 3D-printable stuff, from backs to whole cameras. Problem is, once you go for materials better than PLA (laser sintered nylon, for example), you can’t print them with home printers. A professional 3D-printing service will charge a good money for all the parts needed… to the point it doesn’t make sense to DIY.

So, maybe a medium-format panoramic isn’t an affordable DIY project.

 

[fdonadio]

One of the concerns with just widening the gates on a roll holder is that the amount of film passed over the gate when it is rolled won’t change, so I’d expect overlapping frames.

Have you seen my post from a few years ago on converting a Kodak 3A (122) to roll film? Others have done similar. Im still wanting to refine the film plane/gate by using better materials and contemplating a red window option, but it worked and I wasn’t disappointed with the Rapid Rectilinear performance. Those cameras can be a cheapskates wet dream. I know…

Maybe I should go back to this approach. I saw one of these cameras in person and was really afraid it would have lots of film flatness issues. Maybe I’m wrong.

 

[Donald Qualls]

once you go for materials better than PLA (laser sintered nylon, for example), you can’t print them with home printers.

People print ABS on home printers. Also TPU. And there are light-proof PLA varieties with either glass or carbon fiber reinforcement in the filament. PLA works fine for camera parts as long as you don't leave it in a hot car...

 

[BrianShaw]

Maybe I should go back to this approach. I saw one of these cameras in person and was really afraid it would have lots of film flatness issues. Maybe I’m wrong.

… and maybe you’re right. Im a bit more lenient about film flatness when being a cheapskate. If I were to do “critical “ photography it wouldn’t be with a cheapskate-modified camera.

But in my experiment tje film flatness wasn’t obnoxiously defective upon viewing negative with eyeballs alone.

 

[mmerig]

One option is to find a cheap Graflex 4 by 5 (or some other suitable camera) and use double-sided holders. Modify a spare dark slide so only the top or bottom half* of the film is exposed, so you get two shots per side. It won't be 6 by 12 cm, but it will surely be panoramic.

*better to make it a bit less than half so there is an unexposed margin between them.

 

[AnselMortensen]

Or find a film back from a WWII Torpedo camera and do 6x17 on 120 film natively.
Usually around $100, maybe less if you look around.
It will take some DIY finagling to mount it, or to 3D print a body for it.

 

[reddesert]

Thanks for the work and confirmation.

Maybe the RH-12 and RH-10 are the same, only with a different advance mechanism. RH-8 is probably different (bigger) but doesn’t look modifiable either.

I thought too much about this and didn’t see the clear fact that Graflex backs are limited to 6x9 (2x3”). I was hoping I could save a lot by modifying an RH-12 or RH-10, but now it seems clear I was hoping too much.

So, my only choices are now a DaYi (and other Chinese lookalikes) or a Horseman ($$$).

There are 3D-printable cameras, but printing using good (stable, resistant and good looking) materials costs as much as buying one of these backs.

I think I should stop being a cheapskate, haha!

The Graflex RH 4x5 roll film holders are more or less the same roll mechanism as the roll film holders for a 2x3 camera, but mounted to a larger rectangular plate that fits in a 4x5 camera. So there's no way to turn them into a 6x12 back; they are only natively about 3-1/4" wide image area and the rest is mounting plate.

There was a Cambo/Calumet slide-in 6x12 holder, like the 6x7 C-2 but in 6x12, but it was very expensive when new and is now quite rare I think. Even more so for the Sinar equivalent.

It wouldn't surprise me if there is a design for a 3D printable back that you could send out to a printing service.

Or just buy a DaYi holder/back. They aren't "cheap" but if you are going to run a lot of film through it, the film may cost more. And you can probably resell it for not much less than you paid for it. I don't use the resale argument often because I'm bad at selling stuff or understanding demand trends. But for a relatively niche item like a 6x12 holder, where there's likely to be some demand as long as 120 film exists, and especially since the back is simple and unlikely to ever un-repairably break leaving you with a sunk cost, it makes some sense.

 

[ivan35mm]

Reminds me of this: Homemade 6x14 & Handheld 6x14 Version (Utilizing the same back from the other link)

This guy took two 6x9 roll film backs, sawed them in half, then glued them back together. Sure, it's not very pretty, but with some patience, i'm sure any aesthetic issue could be resolved (masking off areas you don't want glue to go, reverse engineering certain components in CAD, 3D printing new parts, etc)

 

[OAPOli]

I'm aware of 6x12 cameras using a modified Mamiya press back. Looking at mine I think 6x12 is pushing it? Splicing a pair would also be doable.

Our own @dirkfletcher splices two 6x9 cameras to make a 612.

 

[Donald Qualls]

Another option would be to splice some length into an Adapt-A-Roll Six20 (or sacrifice two). These have a simple "click" ratchet at the turn around, and you advance by ear, so it would be easy to advance by the correct number of clicks. Most will feed from a trimmed 120 roll, though they do require a 620 spool for takeup. They mount under a spring back or in a 4x5 Graflok (there may also have been one that fit 2x3 cameras). You might need to splice some extension on the 120 leader, however, for a 6x12 version.