Another Minox question

Why don't we have a subminiature forum separate from "Lo-Fi" -- many 110, 16 mm, and Minox format cameras are far from Lo-Fi aside from the negative size.

But really, that's not the question I wanted to ask. Rather, how do I tell if my Minox daylight loading tank is the original version that would accept 50 frame film, or the later one that only took up to 36 frames?

You can tell it by the stop ring that has to be dropped into the tank. A 50 exp tank has a stop ring that has a hight of less than an inch, the difference between 50 and 36 exp. being not that much. A 36 exp tank has a stop ring of much more height, the difference between 36 and 15 exp is more than half of the hight.

Stop ring?? Now I need to check my tank when I'm home, I don't recall seeing a stop ring. The helical part screws all the way down, so the stop ring may not be with my tank. And nothing in the instruction sheet (which I do have) mentions shorter rolls or a stop ring.

It’s a separate bakelite tube piece that you drop in the tank.

...and it should be mentioned in both versions of the instructions sheets...

Okay, let me look at the instructions again -- there were multiple sheets, I thought the others were just the same thing in a couple other languages (the next one had Spanish on the front).

Okay, I spotted a set of instructions online that are explicitly for the 50 frame version, and they call for more developer; the tank I have (and the developer package) wants 40 ml, while the instructions I found (dated from 1970) mention 53 ml (or 65 if developing 36 exposures in the 50 exposure tank without the stop ring). When were the 36/15 tanks introduced -- wouldn't it have been after the C came out, since all III/IIIs/A and B models could take 50 frame films?

Yes, they switched to 36 in 1969 with the launch of the C model.

Okay, I'll have to look for the print date on the instruction I have (and turn the tank base over to see if there's a stop ring inside -- though I don't think there is, because the core screws right down to the bottom). I presume I could make one out of suitably sized PVC pipe (seems like 1 1/4" Sched 40 should be close).

Looks a bit like I may have to get a Paterson compatible reel and master the technique of jamming the film end with a piece of foam to keep only the base side in contact with the plastic. Modern (hand loaded by Blue Moon or FPP) film doesn't have the buttonhole in the end anyway, so I'd have to punch it for the core screw.

Hmmm. Looking at some eBay listings, it also appears the 50 frame tanks have 7 turns to the helical core, while the 36 have only five. That I can verify when I get home...

You can find some creative ways to make Minox reels at:

www.subclub.org/creative/reel.htm

Okay, I checked my tank and instructions. The instructions were apparently printed in 1955, when the only Minox were Riga and III/A and everyone shot 50 frames. It has seven turns of the helix on the core, and NO STOP RING at all, nor do the 1955 instructions even mention one.

I was incorrect in recalling 40 ml for the tank -- it's "fill until you see liquid in the neck" -- it's only the Minox developer and fixer that call for 40 ml of water (which seems like it would be enough for the later 36 frame version of the tank). The instructions I found online say I can develop 36 exposure film in the 50 frame tank without a stop ring, I just have to use the same volume of liquid I'd use for a 50 frame roll (I guess I stop screwing the core in when the film comes taut from its attachment to the takeup core in the cartridge; if I pull it off the spool it'll be loose in the tank, which seems bad).

It looks like I can use a common hole punch to punch a hole in the film tail about 3/4 inch from the end to catch the screw after the end is under the spring tab; those aren't hard to come by, though I might have to shop around for one barely big enough for the screw head, as a regular punch is 6.35 mm diameter and the film is only 9.2 mm wide...