Leica film cassettes useable with new Ms?
As I mention half way down the M7 review, you cannot use reloadable Leica metal cassettes with newer M6, M6TTL, M7 or MP cameras. The reason is due to the lack of a film-locking notch in the base-plate of these models, which is required to open & close the cassette.
(In Nov 2005 Tom A remarked he has actually made a few special-order rapidwinders with the notched-base. It's not a general production item though. Contact Tom to discuss.)
M6(TTL) works with older base plate
What if you swap the base-plate with an older M version, say from an early M6 or M4-P - will this now work? The good news is that despite claims to the contrary, for the M6 & M6TTL it will. By using an older base plate, reloadable film cassettes will now load and work fine with your M6(TTL).
In May 2004 I bought a couple of Leica cassettes (see below) and tested this myself. I replaced the standard "notchless" M6TTL base with a "notched" one from my M4-P and… it worked. The canister fit into the film chamber; the base plate went on and closed properly; film transported cleanly until the end of the roll; it rewound correctly and finally, the film cassette was locked as normal when the base plate was removed.
So if you have a M6TTL or later-model M6, all you have to do is scrounge a base plate from an older M and you're ready to go.
M7 and MP - film chamber too small
Unfortunately the base plate switcheroo won't work for the newer M7 or MP. This is because the film cassette cannot physically fit into these models' smaller film chamber cavity.
Why the smaller chamber size? Best guess is that extra room was needed for the M7 AE & TTL electronics. As the non-AE MP also has the smaller size, it indicates Leica, as a sensible cost saving measure, is probably using the same body moulds for both models.
How to load & use cassettes
Okay, so how do you use/reload cassettes for use with camera models which support them (M3, M2, M4, M4-2/P & M6)?
This was covered in extensive detail in a discussion on photo.net in April 2004 at <Photo.net: #0083CY>.
Furthermore, in March 1999 Tom Abrahamsson supplied the following detailed (and slightly whacky) instructions:
Cassette types & construction
[…] There were basically 3 kinds of Leica cassettes.
1. The very first version for the 1920's Leica screwmount camera (now a bit of a collectible)
2. the 2nd version with the black knob, or "lug" on the top for the LTM Screwmount cameras
3. the final incarnation "IXMOO", where the cassette has a chrome lug on top for M-cameras
The good news is that these cassettes are backwards compatible - the 3rd "M" version (IXMOO) works fine in the older cameras, but not the other way around.
The cassette itself comes in three parts (how Germanic do you want it to be!), a center spool with a spring loaded set of teeth to hold the film end, an inside shell and an outside shell, both made of solid brass.
They are useful, but they are very heavy, more than double the weight of the regular film cassette (for the retentive types, 46.1 grams for the Leica cassette, versus 20.3 grams for a regular cassette -36 exp/ HP5+ in both). If you pick up one of the Leica Manuals from the 50's or 60's you will find all the variations of these cassettes listed there. Great reading for all the other stuff too. […]
To load it you enter your darkroom, and in total darkness, open the can of 100ft long film, disassemble the cassette and unspool an approx. 6 ft length of film, realise that you cant find the scissors or the Exacto knife. Pack everything down, find the scissors, go back in the darkroom, turn off the light, open the film can, listen in amazement at the sound of film, having spent a substantial time under tension, unwinding itself and draping itself on you and on the floor. You patiently find the end and with the scissors cut a V-shaped end on the film, feed it in the spring loaded slot and measure of an appropriate length of film (about the length between your fingertips if you extend your arms fully) and cut it of. By this time you have probably cut your fingers already doing the V-groove. Have no fear, the drops of blood does not affect the processing time! Now you wind up the film on the spool, insert it into the inner cassette shell, pull out a piece of film and insert the inner shell in the outer shell - losing the little end that stuck out through the slot in the inner cassette. After a while you manage to get the film through both the slots, snap the cassette shut and start on the next one.
All of this is done in total darkness, accompanied by words your mother told you not ever to use and chasing implements like the scissors, knifes, center spools that has rolled on the floor- all the same wondering if you got the emulsion side the right way up! It is great entertainment for anybody outside your darkroom door. Once you have got the hang of it - and the scars on your fingertips have healed - it is a good system.
The open/close mechanism
The older M's M1/ M2/ M3/ M4/ M4-2/ M4-P and the earliest M6's had the appropriate base plate lock for opening and closing these cassettes. Around 1990 they changed it to the current lock (a flat disc). If you look at the older baseplates, you will notice the indent and slot on the lock - the chrome lug fits into the slot, the curved piece of metal that stops the lock from turning full circle also pulls the locking spring of the cassette out of the way. When you load, you drop the cassette in the camera, put the baseplate on and turn it to locked position and this action opens the cassette so the film can move through the "" slot which opens up. You don't get scratches from the opening as there is no felt-trap to accumulate grit, the friction is reduced and once the film is exposed and removed from the camera it is in a pretty solid container.
There are some caveats to using these cassettes; if you are shooting with Estar based films (Tech Pan, certain Ortho films) don't use the cassette - you cant rip these films off, they have to be cut and the "one-way" spring trap in the center spool jams and you have to unscrew the springs in the spool (very small black screws that tend to disappear).I have also found that using Infra red emulsions can create problems - the cassette is very safe - BUT the large opening can fog film.
Where to buy
These cassettes show up at swap meets everywhere. The price seems to vary, from a reasonable $2-5 for the cassette, add another $2-3 for the aluminium or Bakelite container with its Leica logo - to the highly unreasonable $25 or more that some dealers ask. Any large dealer will have some in stock, usually in a box of assorted Leica pieces that he/she has despaired of ever selling (you know the box with the Reprovit camera mount, the 35 contact printer, the Benser baseplate and other assorted goodies).
I use mine for loading large quantity of film - occasionally I get movie stock, Super XX, Agfapan 250, etc. in 400ft cans. I lock myself in the darkroom for a couple of hours and load 65-70 of these cassettes and there is a month to 6 weeks shooting supply. I saw a different version of this loading system some time ago. A friend brought back from Russia a 64 ASA black/white film (it must have been one of the worst marketing gaffes ever made. The name of the film was "Chernobyl")! The camera store had the film in little alloy foil packages, it contained a center spool and the film wound up on it. The user supplied his/her own outside cassette shell. Not a bad film, slightly pre-fogged, but considering that it cost something like 8 cents/roll, not a bad deal.
It is good to remember how convenient our 35mm film system is - at least we don't need a changing bag to reload the film. Of course there were tools to make it easier to use these cassettes, the famous film cutting template, the table edge mounted winder and my favourite, the brass rod for turning the cassette center spool. Leica was somewhat accessory happy in the first 50 years of its existence (look at Jim Lager's volume III, accessories).
Using Daylight bulk film loaders
If you use the right type of loader, then you don't have to muck around with lengths of film in the dark.
David Li noted in Aug 2004:
You can use daylight bulk film loaders to load cassettes, but have to have a compatible model which can load and close the cassettes properly. One such loader is the Watson 66B loader, which you can probably find on eBay for around ten bucks.
In Oct 2004 Charlie Trentelman added the following:
[…] Several bulk film loaders can be used to load a leica cassette without all the muss and fuss in the darkroom - you can do it with the lights on, as I have done many many times over the past 3 decades.
A Weston does it best, but several others still sold new can as well. If you look inside you see that the knob in the loader that connects with the top of the cassette has holes that the knob on the cassette fits in to. After you wind the film onto the spool, you turn the outer knob on the loader and it turns that inner disc, which turns the knob, which closes the cassette. It is best to do this in dim light because sometimes the cassette is tight and it doesn't close all the way. At worst, you fog the first layer of film a bit.
Otherwise, the procedure is the same - open the casette, put it in the loader, insert the film into the take-up spool after first cutting a V on the end (I find trimming the film sprocket holes off the sides does it well) making sure to put it in the side of the slit indicated by a small hash mark, then close the film loader's lid, open its gate, and proceed as normal.
Simple. And I've never had to slice my finger in the dark :?)
For general infomation about film bulk loading, see The Bulk Loading FAQ by Josh Wand.
Additional Cassette tips
Tom A's remarks are pretty comprehensive. On the strength of them I went and bought a couple of cassettes myself in May 2004. The following are a few tips & gotchas I learned from the experience:
How to open
To open a cassette, pull on the protruding chrome prong beside the letter "Z". By pulling it outwards, the prong disengages a small catch, which in turn lets you rotate the chrome knob clockwise to open the "" film access slot (and also pull the cassette apart if you wish). I mention this because neither the shopkeeper nor I knew how to do it at first, and we had to fumble around for ages before we figured it out. (Mnemonic: in German "Auf/ Zu" means "Open/ Close" - see this March 2006 discussion at <Photo.net: #00FrOK>)
Test inside a camera
Bring a camera to test the cassette. This Is Crucial! Many cassettes would open and close without problems in our hands, but were useless when inserted into my M3 (the base-plate wouldn't close properly).
These things are at least forty years old, so you can expect a lot of brass discolouration. Generally speaking this is not a problem, and may even work in your favour when negotiating a cheaper price. As long as the cassette opens and closes smoothly inside your camera, you'll be fine.
How to clean
If the brown dullness bothers you, it can easily be cleaned with any domestic brass cleaner. I used a paste called "Shine" by Autosol. Applied with a soft cloth and a bit of rubbing, your cassettes will end up looking shiny yellow and like new. The more corroded areas inside notches or corners can be scrubbed with a (spare) toothbrush & wooden toothpicks. A warning about cleaning the interiors though - go easy as you can strip the black anodization if you aren't careful.
Get the bakelite canister
If you're going retro then go all the way. Get the matching black Leitz canister to house the cassettes! Don't worry if there is writing on the white disc on the screw-top lid, this can easily be removed with a pencil (or ink) eraser.
There's no need to completely disassemble the cassette. With lights on (and obviously the exposed film removed!) open the rectangular film slot, push any remaining film through the toothed-notch in the film spool, and rotate the spool until it's aligned and ready for a new length of film. Turn out the lights, push in the "v" film-tip into the spool, and wind-on 1.7m of film. Because I don't have a compatible bulk film loader, I use a plastic clothes-peg inserted into one end of the film-spool knob to make winding easier.
In short these things are pretty cool. Provided you keep them clean, they'll easily last you a lifetime.