I  recently decided that turn counting is the only way to advance the film on my Stereflektoskop and Sputnik.  Particularly with the Stereflektoskop, I was fogging too many good pictures while advancing the film by reading numbers on the film back.  My new method also allows me to get back to picture taking much faster, especially in dim light.  Surprisingly,  it is just as accurate as reading the film back.  Since the Stereflektoskop's film gate allows no space between stereo pairs it is very easy tfor me to spot any overshoot or overlap on the processed roll of film.  I find occasional errors of 2mm but by far most winding errors are less than 1mm.

I have gotten this result by calibrating my film advance knob in percentage of turn.   For ease of viewing the calibration scale covers only the front half of the film advance knob.  So I have two pointers on my knob 180 degrees apart, one red and one yellow.  I have also attached a film counting strip the the back of the camera which indicates current frame number and amount to advance the film. After I have taken a picture, before I do or think of anything else, I slide the counting strip to the next frame number. Film advance is always two full turns plus some fraction of a turn, depending on how much film is in the take-up spool. The amount to advance after any shot is indicated on the counting strip, for example, as "R42". This tells me to advance the red pointer two full turns and then a partial turn up to the 42 mark on the calbration scale. Actually the scale is marked at each 5% of a turn, but it is easy to eyeball any fraction of the 5% span to 1% precision.  The winding knob does back off about 5% of a turn when released, so I always read the setting with film taught.

As cumbersome the above procedure might sound, it is quick and completely intuitive. I have already gone through ten rolls without miscounting turns or making a double exposure. The trick is to "program" yourself to consider advancing the film counting strip as being integral with releasing the shutter. That I have done. A couple of times, however, I did get distracted and forgot whether I had actually advanced the film. Whether I did is easily confirmed by checking whether the knob pointer corresponds to the position indicated on the counting strip. As I said, I have yet to make a film advancing mistake. I could only wish that my focus and exposure settings were that flawless.

Oleg Vorobyoff

>
> I recently decided that turn counting is the only way to
> advance the film on my Stereflektoskop and Sputnik. -
> snip -
>
> . . .The amount to advance after any shot is indicated on
> the counting strip,
> for example, as "R42". This tells me to advance the red
> pointer two full turns and then a partial turn up to the
> 42 mark on the calbration scale.

--- In MF3D-group@yahoogroups.com, John Thurston wrote:
There is, I think, far too little precision in
> the lever advance to permit this process to be used on the
> TL120. Now, someone please go get their TL120 and prove me
> wrong!
> --
> John Thurston
> Juneau Alaska
> http://stereo.thurstons.us

You are partly right John. I have taken up your challenge and have
just run through an old dud test roll of Velvia through the TL120 a
few times. After three consecutive attempts I found it precise
enough to give quite consistent figures, but a little annoyingly hard
to count because of the way the crank mechanism works. Firstly, the
crank seems to have 14 clicks of the ratchet mechanism per full crank
of the film advance lever, so the following figures are shown as
cranks, then individual clicks representing a partial crank of the
lever. The five sets of figures are for starting at frame 1 in the
window and so they will show frame 1 to 3, 3 to 5 and so on.

1 to 3 = 8 cranks and 4 clicks
3 to 5 = 7 cranks and 11 clicks
5 to 7 = 7 cranks and 4 clicks
7 to 9 = 6 cranks and 11 clicks
9 to 11 = 6 cranks and 5 clicks

The annoying part is that if you have to use a partial crank to start
the film on 1 showing in the window, when you go to wind it on after
that first shot is fired, the mechanism will only start clicking
where it left off on the previous crank. This makes it very time
consuming (at least for me) in trying to add up all the clicks and
cranks to equal the figures I have just presented. For instance, to
get the first set of figures of 8 cranks and 4 clicks you might have
to start off with say 9 clicks to complete the first crank. Then you
would need to have 7 full cranks, then a further 9 clicks (if my math
is right) to get to the equal of that first set of figures. Fiddly
and time consuming to say the least. Also this would be of little
help to Mark who seems to shoot in music venues as he wouldn't have a
hope of hearing the clicks. I am doubtful if the clicks could be
reasonably felt through the thumb.

These figures are for centering the number in the red window.
Naturally they would be a little different using John's good
suggestion of starting short and finishing long to make use of every
last bit of film - but either way, it is a frustrating counting
process.

I would use the counting table only in desperation, but it is much
easier just to keep plenty of small torches on hand. I personally
use a small LED penlight which has a good little gooseneck on it
allowing it to be clipped to the brim of a cap or clipped to a shirt
pocket and used hands free.

By the way, best to carry out your own tests if you wanted to use
this method. Numbers would possibly vary from different film
types/brands and also may be different if anything has changed in the
film advance mechanism throughout the various model variants of the
TL120.

regards

Harry Calderbank