Classic "cinch" marks...

[adrian bastin]

Josia, as that clip is not what pulls the film along when advancing it, there should be no need for it to hold the film very tightly; in fact its quite easy to turn the spool against its grip on the winder spindle. It has to be that way because the sprocket and the spool turn at different speeds according to how much film is on the spool; at the end of the film the winder spindle will be turning a lot more that the spool itself.

 

Sorry, there must be a simpler way of saying that.

[adrian bastin]

Josiah, here's the 'H' I dropped.

[adrian bastin]

Does the Leicavit engage the spindle ? If so, there is a clutch there already. The strain comes on the sprocket gears and that IS transmitted directly to the film. So there's your answer !

[adrian bastin]

I garbled/mangled that. Let me try again:- The Leicavit, if it engages the spindle, is powering the sprocket, with no clutch. So when you get to the end of the film there will be quite hard tug, but it will not be on the rolled up film; that is still being protected by the spool-clutch. So it isn't the 'answer' I said it was. But watch out for those gear teeth.

[jsc1]

Adrian Bastin...

 

I do appreciate your help.

 

I'd have to see a IIIF parts diagram to be remotely/entirely certain that I understood what

you are saying. The Leicavit has a shaft with a protrusion which engages a notch on the

spindle which holds the take-up spool. The Leicavit lever turns the shaft, which turns the

spindle and the take-up spool.

 

So, please correct me if I misunderstand, the advance mechanism, and the Leicavit in

particular, won't/can't "cinch" film that has reached the end. This is because of a "clutch"

that isolates the cassette.

 

That understanding would seem to leave only the rewind process as an explanation for the

cinch marks. Right?

[jtk]

1) It might have helped somebody (not me) if you'd mentioned Leicavit initially. Do you have that problem with ALL your (plural) LTMs, or just those with Leicavit?

 

2) Where do you find 5-decade-old references to "cinch" marks?

 

3) If someone last considered it a problem 50 years ago, that does not make it "classic."

 

"I was describing the "cinch" marks as "classic." The marks on my negatives look exactly like "cinch" marks described at least 50 years ago. Hence, they are justifiably described as "classic," i.e. they precisely agree with the earliest descriptions."

 

4) If you've been having that problem since Hector was a pup, you may be drawing attention to another classic problem.

 

5) Very nice tree tryptich.

[adrian bastin]

Josiah. The clutch isolates the take-up spool. The winder's tug is on the bit of film (with the last frame, or part frame on it) attached to the empty cassette's spool, and is exerted by the teeth of the sprocket.

 

It has to be when the film is back in the cassette and wound tight to pull free of the take-up spool. if you do as Al says, it should cure it.

 

Adrian.

[jsc1]

Adrian Bastin...

 

Thanks. I understand these "mechanical marvels" a little better now.

 

After all this "work," I do believe that both of my IIIf take-up spools are original and are

possibly a bit more sophisticated, by design, than E. Leitz originally revealed. On my

take-up spools, the "spring" that holds the film is punctured by 9 holes in the shape of an

"arrow." The "tip" of this "virtual" arrow adjoins an obstruction, a "film stop," and you can't

push the film leader beyond this point.

 

As I reflect upon this feature now, I realize that these holes would enable "calibration," of a

sort, of leader attachment. Simply insert the leader to a particular "hole" that works....

without "cinching."

 

For some, this will, no doubt be further evidence of the "genius" of E. Leitz...

[jsc1]

"Jonathan Reynolds , feb 28, 2006; 11:30 a.m.

Hardener isn't going to help if the marks arise in the camera, before processing. That

would be like shutting the stable door after the horse has bolted!

The advice I've read (from Ilford) is not to use a hardener with film unless you absolutely

must."

 

Finally.

 

And if you are uncertain? Is adding "hardener" a rational, and cost-effective, thing to do if

you simply don't know if the "marks" are pre- or post- processing?

 

The End.

 

Are modern emulsions softer? Al (Kaplan)? Help?

[jtk]

Consider film base thickness. I've not bothered to measure yet (micrometer) but it seems current Fuji Neopan is thinner than my ancient Ilford HP4 and Kodak misc, maybe thinner than recent Ilford Delta 400. Maybe. Also, I have the impression that it's more brittle, stiffer than any of the other films, more vulnurable to tearing and perhaps sprocket hole chipping within a Barnack.

[john_wire]

"Swapped" a fresh roll of "made in China" Kodak 800-4 in the Colonel's Zorki this morning. Interestingly, discovered the Zorki takeup spool has a tab on the spool spring that holds one of the first few film leader sprocket holes from slipping, depending on how far you insert the leader.

 

So, remembering Al's observations and instructions, the FSU guys don't have to hold their breath when inserting and loading, the spool spring is holding their leader. This could explain why Zorki users are not frustrated and holding their breath after a loading experience.

 

Now, if you don't realize your leader is held by this tab, and rewind the film fully back into the cassette, overcoming the resistance of the film leader held by the spool spring leader lock, you end up with film debris from the torn sprocket holes. And maybe some "cinch" marks, "ouch".

 

None of this has anything to do with Leica's. It should be noted however, that "imitation is the highest form of flattery".

 

I wish someone would let me know if chinese film is better than US film and why. Regards.<div></div>