Jump to content


Photo

65mm stock indexing


  • Please log in to reply
5 replies to this topic

#1 Phil Rhodes

Phil Rhodes
  • Sustaining Members
  • 11938 posts
  • Other

Posted 11 February 2010 - 01:04 PM

OK, so indexing on 35mm stock looks something like this:

1234+12

where 1234 represents feet, and 12 represents frames. This works for 35 (exactly 16 frames per foot) or 16 (40 frames per foot) or even 8mm (80 frames per foot).

But what d'you do about 65mm five perf (12.8 frames per foot) or god forbid 15 perf (4.267 frames per foot)?

Rounding things to the nearest frame boundary gives a sequence that looks like this:

74+00
74+01
74+02
74+03
74+04
75+01
75+02
75+03
75+04
76+01
76+02
76+03
76+04

This might be a perfectly valid way of indexing frames on 65mm stock, but it's ugly and counterintuitive that we never see 75+00 or 76+00.

What's the solution here? How is this supposed to work?

P
  • 0

#2 David Mullen ASC

David Mullen ASC
  • Sustaining Members
  • 19759 posts
  • Cinematographer
  • Los Angeles

Posted 11 February 2010 - 01:45 PM

Didn't Kodak change the keycode placement on 65mm a couple of years ago for this reason?
  • 0

#3 K Borowski

K Borowski
  • Basic Members
  • PipPipPipPip
  • 3905 posts
  • Camera Operator
  • I.A.T.S.E. Local # 600 Eastern Region

Posted 11 February 2010 - 01:46 PM

It could be even uglier, if you use meters :-p


In seriousness, 4-perfs are 3/4 inch (or close enough), so shouldn't each frame be 3/16"? Or, for those of you that are Imperially/fractionally challenged, that is 0.1875"/0.47625mm.

I know that this isn't exact, and is even more complicated now that pitches have changed and with acetate vs. estar (8 perf.'s on acetate is NOT 8 perf.'s on ESTAR), but can't you just bypass all the measuring BS and base measurements on perf.'s flat-out?


Of course, NLE editng, keycode, and inked in edge marks aren't my department, so I apologize if I am missing your point completely.
  • 0

#4 K Borowski

K Borowski
  • Basic Members
  • PipPipPipPip
  • 3905 posts
  • Camera Operator
  • I.A.T.S.E. Local # 600 Eastern Region

Posted 11 February 2010 - 02:22 PM

EDIT: 5/16" for 5-perf.
  • 0

#5 Dominic Case

Dominic Case
  • Basic Members
  • PipPipPipPip
  • 1357 posts
  • Other
  • Sydney Australia

Posted 11 February 2010 - 08:19 PM

David could be right.

But this seems to be the same problem that comes up with 3-perf 35mm, with 21 1/3 frames per foot.

I seem to recall that this flummoxed most of the neg matching software around in the 90s. The solution involved defining a reference frame at the start of a shot by the position of the Keycode reference dot relative to the top perf of the frame. You don't need to see the actual way the computer referrs to a given frame, so ugly counter-intuitive number sequences aren't a problem. (At least not any more than they are in 3/2 pull down, dropframe timecode, or days of the month for that matter.)

In the case of 65mm, the defining issue is to know which footage numbers in a sequence actually have 00 frames. The next two won't, but where to start??
  • 0

#6 Phil Rhodes

Phil Rhodes
  • Sustaining Members
  • 11938 posts
  • Other

Posted 11 February 2010 - 09:39 PM

Evertz have cooked up some sort of solution, which they claim other people are using, for 3-perf 35:

http://www.evertz.co...urces/3perf.pdf

...but it seems barely less involved than just rounding to the nearest perf.

P
  • 0


Wooden Camera

Media Blackout - Custom Cables and AKS

Visual Products

Tai Audio

Willys Widgets

CineTape

Technodolly

FJS International, LLC

Aerial Filmworks

CineLab

Broadcast Solutions Inc

The Slider

Glidecam

Abel Cine

Rig Wheels Passport

Metropolis Post

Opal

Paralinx LLC

Ritter Battery

Gamma Ray Digital Inc

rebotnix Technologies

Aerial Filmworks

Opal

Media Blackout - Custom Cables and AKS

Broadcast Solutions Inc

Technodolly

FJS International, LLC

Wooden Camera

Paralinx LLC

Gamma Ray Digital Inc

Rig Wheels Passport

The Slider

Glidecam

Ritter Battery

rebotnix Technologies

CineTape

Abel Cine

Willys Widgets

Metropolis Post

Tai Audio

CineLab

Visual Products