ISO 69:1998

Overview

ISO 69:1998 - Cinematography - 16 mm motion-picture and magnetic film - Cutting and perforating dimensions specifies the cutting and perforating geometry and tolerances for 16 mm motion‑picture and magnetic films. It covers films with one or two rows of perforations and defines two categories: general 16 mm film and manufacturer‑designated professional camera films with tighter tolerances. The standard applies to safety raw stock as described in ISO 543 and gives dimensions measured at the time of cutting and perforating under a controlled atmosphere.

Key topics and technical requirements

• Film types covered: 16 mm motion‑picture and magnetic films with one or two rows of perforations; professional camera films with tighter tolerances.
• Reference conditions: dimensions apply at cutting/perforating with film adjusted to 23 °C – 1 °C and relative humidity (50 – 2) % (conditioning/testing atmosphere).
• Perforation geometry: key dimensions and tolerances are specified (see table in ISO 69). Representative values include:
  • Long pitch B = 7.620 mm; short pitch B' = 7.605 mm
  • 100‑perforation interval L = 762.0 mm; short‑pitch L' = 760.5 mm
  • Hole margin C = 1.830 mm, hole position D = 1.270 mm, edge margin E = 0.900 mm
• Professional tolerances: manufacturer‑designated films have tighter repeatability limits across any 50 consecutive perforations and stricter limits between consecutive perforations (specified in the standard).
• Pitch choice and printing: the standard explains use of long pitch (B) and short pitch (B') to accommodate continuous‑sprocket printing. Typical pitch differential target is about 0.3%, with manufacturers often aiming for originals 0.2% shorter than print film to allow for processing/ageing shrinkage.
• Low‑shrinkage film: defined in Annex A - film that shrinks no more than 0.2% under specified handling, processing and storage conditions.
• Reference edge and positioning: rules for identifying the reference edge (perforation side or winding convention) and guidance for equipment to use the reference edge and a consistent perforation (+3 perforation recommended) for vertical positioning.

Applications and users

ISO 69:1998 is practical for:

• Film stock manufacturers and film processors (cutting, perforating and QA)
• Camera and projector designers, telecine and printer manufacturers (mechanical registration and sprocket design)
• Post‑production labs, archives and restoration facilities (compatibility and dimensional stability)
• Equipment designers aiming to optimize image steadiness and cross‑printer compatibility for 16 mm workflows

Related standards

• ISO 543 (safety raw stock film) - normative reference
• ISO 544 (standard atmospheres for conditioning/testing) - referenced for conditioning
• ISO 25:1994 (camera usage reference mentioned in Annex A)

Keywords: ISO 69:1998, 16 mm film, perforating dimensions, cutting dimensions, long pitch, short pitch, low‑shrinkage film, film manufacturers, camera films, motion‑picture film.