Leica LTM Unequal distances from edges of film

Leica M39 screw mount bodies/lenses
Also:
Be advised that the spring only has to exert a small amount of pressure on the bottom of the cassette, so a light one is preferable. It should fit around the stem of the cassette, with clearance, and taper into the hollow of the latch body. Bring a cassette to the hardware store. You can cut the spring to length as it will probably be to long.
Art
 
Jaap, the thickness of the film doesn't matter if the pressure plate does its job, since the emulsion will be at the correct distance from the lens flange: that is, pressed against the guide rails. Daniel, does the film travel *between* the rails or do its sprocket holes travel *over* the rails?
 
The problem with using tape over the spindle, is that the spindle turns when you advance or rewind. This has the potential of chewing the tape and making a mess. The spring clears the spindle and rests on the bottom of the cassette and lets the spindle turn freely.
Art
 
I will try to post a photo today of the spring fix. When there is no film in the camera, the spring stores nicely on the end of the take up spool.
Art
 
Spring Fix

Spring Fix

This is what the spring looks like in relation to the camera body and cassette.The spring is thin and light. A heavy spring is not needed.
Art
 

Attachments

  • Spring Fix 4.JPG
    Spring Fix 4.JPG
    148.9 KB · Views: 0
Hmm, posted four pics, one came up. Trying again.
 

Attachments

  • Spring Fix 1.JPG
    Spring Fix 1.JPG
    139.5 KB · Views: 0
  • Spring Fix 2.JPG
    Spring Fix 2.JPG
    138.3 KB · Views: 0
  • Spring Fix 3.JPG
    Spring Fix 3.JPG
    154.4 KB · Views: 0
One of the last posters on that thread said that he liked the picture speading into the sproket holes (a feature for him) whereas others find it a fault. It is also a standard computer software representative's reply when a customer complains about how a piece of software functions. "Oh no, sir. It's supposed to.....blah, blah, blah."
 
FrankS said:
One of the last posters on that thread said that he liked the picture speading into the sproket holes (a feature for him) whereas others find it a fault. It is also a standard computer software representative's reply when a customer complains about how a piece of software functions. "Oh no, sir. It's supposed to.....blah, blah, blah."
Click to expand...

Frank, I got it now, I missed that in the other thread. I like your analogy to the computer rep. How true.

Art
 
I knew I had the answer somewhere. The 44th edition of the *Leica Guide* (Focal Press) speaks of two versions of the Leitz 3-piece reloadable cassette. The Model N, with a chrome plated knob, is said to fit all M models up to the M4 (but not the M5) -- as well as all screw mount bodies. The earlier Model B, with a black knob, fits only the screw mount bodies. It is 2.2 mm longer than the later one, which is presumably the same size as the cassettes made by Kodak and others. In a screw mount body, then, any cassette other than the Model B must be raised by 2.2 mm in some way. Of the various ways of doing this, that which uses a spring seems to be the best because it is so simple and dependable.

The little book, published in 1975, does not speak of any Leica model later than the M4.
 
This explains why my IIIc is never going to take photos like HCB IIIc whaever I do. It only gets 'B' black knob cassettes for food.

I had thought about the IIIf enhancement (the finger) but since I had never seen a problem.

Perhaps if I start using normal cassettes my pictures will improve?

Noel.
 
Daniel, the earlier cassette was made for the screw models and fitted them perfectly. Had the M models been made to take the same cassettes, they would not properly have taken the mass produced cassettes used by an overwhelmingly larger number of photographers. Leitz only changed with the times, possibly thinking that those who continued to use the earlier series of cameras would also load their own cassettes. Few users may even notice that the exposed area is closer to one edge because it is only a little closer and is masked off when a print is made.

The long edges of my IIIc's negatives do run over the sprocket holes, but there is nothing wrong at their corners since the pressure plate still presses the film (Fuji C-41) against the rails.

A couple of earlier posts in this thread will show what others say about using tape. It is not perfect. Nor is a spring which may jump away when the base-plate is taken off. A metal washer (shim, if you prefer) would be excellent, but it would have to be kept in place in some way and would have to be of the correct crazy shape.
 
Bob, the spindle will need to rotate freely, so friction must be avoided. Maybe a distance piece of a material other than soft plastic? A tiny roller bearing that fits around the spindle and whose larger, flat side rests against the base plate?

I quoted accurately the source I named. Focal Press books generally give correct information. The question is, 2.2 mm where? Since the same source says that the spindles of the two versions of the Leitz cassette are interchangeable, the difference must be in the inner and outer shells, or at least in one of them. Art's spring fix doesn't care: it pushes the whole damn thing up, as far as it needs to go and no more. "Art's Spring Fix" sounds good too.

Anyone know of a spring -- coil, leaf, whichever kind -- that will lose its springiness as soon as the base plate is opened?
 
payasam

You are right about the tubing. Looks like I will try the spring idea.

Bob
 
Difficult, Andrealed, to manage that without fouling the latch. Can be done, I'm sure, and done again when the spring loses its tension, and done again....
 
You must log in or register to reply here.
Back
Top Bottom