Re: 220 frame counting

[Paul Talbot <ptww@xxxxxxxxx>]

Apologies for the delay in responding to the original
request.  The size of our household tripled immediately
on our return from vacation, as a result of relatives
spending their vacation with us.  Then by the time they
left Tuesday morning I could no longer hold off the
respiratory infection I'd been battling for some time.
I've been pretty much out of commission the past couple
days.

Tom Deering wrote:
> 
> >If you have any recorded details regarding the number of turns,
> 
> I think counting frames is the most difficult issue to resolve.

Not too difficult to "resolve"...

> As a form of entertainment, I worked out a simple spreadsheet to
> estimate the number of turns needed to space frames equidistantly on
> a roll of 220.  This is really just a toy, since I have not actually
> tested it.  This should demonstrate how difficult the winding issue
> is.

Um, well, ..difficult to "resolve to the nth degree of
precision,"
perhaps.  ;-)

> Basically, I measured the thickness of a piece of ruined Velvia, and
> measured the diameter of a film spool.  I wound on a piece of paper
> paper backing up to the point where the film starts, to get the
> diameter right.
> 
> Then I wrote a spreadsheet to add up the number of turns to space the
> film correctly on the film.  The number of turns decreases as you
> shoot because the diameter of the spool increases as you wind film
> onto it.
> 
> shot   diameter    turns
> 1      13.1 mm     5.9
> 2      13.8 mm     5.6
> 3      14.5 mm     5.3
> 4      15.1 mm     5.1
> 5      15.8 mm     4.9
> 6      16.4 mm     4.8
> 7      16.9 mm     4.6
> 8      17.5 mm     4.5
> 9      18.0 mm     4.3
> 10     18.6 mm     4.2
> 11     19.1 mm     4.1
> 12     19.6 mm

Oh boy.  This is way beyond what I've done so far.
 
> So you can see that you would have to keep pretty good track of the
> number of turns  per frame(not so hard) and the number of frames shot
> (much harder, for me at least).

I tend to shoot in bunches...mostly on trips (whether local
or distant), so I go through a roll pretty quickly.  I can
usually recall exactly what I've shot on the current roll
(applies only to the small number of shots on MF rolls, not
a whole 35mm roll).  But I did recently use a scratch piece
of paper to help keep track of the turns so I could refine my
technique, and report the results here.

> However, seeing that the first frame required almost exactly six
> turns,

I think there is something missing in your assumptions.  The
one area I have not yet resolved satisfactorily is how to get
the film to the right starting position.  The 220 paper leader
has two start marks, one for "standard equipment" and one for
"special equipment," or something like that.  I forget which
order they appear in, and I don't know precisely how many turns
are required to advance from either "start" mark to get the
film in a position that places film behind both the left and
right frames.

You mention using paper backing to get to the right starting
point, but don't mention how many turns it takes to get there.
And I don't know how the length of the 220 paper leader compares
to the 120 paper backing up to the first frame.

Also, your chart seems to indicate turns of the spool.  I
have been counting turns of the wind knob, which may not bear
a one-to-one relationship to turns of the take-up spool.  I
may have expected a one-to-one relationship, but the number
of turns you calculate is far more than I have found are
required in practice.  (I should note that my starting point
was to load some used 120 paper in the camera (with film?),
and actually count the number of turns required to advance
it from frame to frame.)

My notes indicate I used the following sequence on film I
shot in September:
  From "standard start" to first frame: 2-1/2 turns; then:
    After pair #        Turns
    ------------        -----
        1               3-1/2
        2               3-1/4
        3               3-1/4
        4               3
        5               3
        6               2-3/4
        7               2-3/4
        8               2-3/4
        9               2-3/4
       10               2-1/2
       11               2-1/2
       12               2-1/2


Unfortunately, I didn't see the uncut film to precisely
evaluate how this advance sequence worked out.  I do know
that I didn't lose any shots to frame overlap.  Most likely,
however, I did lose the first and last (12th? 13th?) to
not having a full left and right frame on the film.

> I wondered how many frames I would lose if I just wound six
> times for each frame.  I modified the spreadsheet and discovered I
> would lose two pairs.  By the end of the roll, there would be 2
> inches between shots, but that's the price of easy 220 frame
> measurement.  Ten pairs to a roll of 220 doesn't sound too bad.

Well, I think an intermediate solution is possible and
advisable.  Don't try to make the spacing exactly the
same as it would be if you had use of the red window:
 - there is some extra film at the beginning and end
   of the roll to work with.
 - if you are using the $1.89 220 from Freestyle, who
   cares if you only get 11 pairs instead of 12?
 - if you do get a small amount of overlap, it may
   not show up when the MF mounts crop the image to
   50x50 (in fact if you carried it to the ultimate
   miserly level of execution, you could possibly
   incorporate intentional overlap and squeeze 13
   pairs on the roll.  But I'm sure not going to mess
   with that approach!)
 - if you get a bit more overlap on some frames, you
   can mount them in the 645 portrait mounts.

So for all these reasons combined, I take a "loosey
goosey" approach to the film wind-on issue.  It thus
becomes not that big a deal, really, IMO.

Paul Talbot