Overview
ISO 17266:2018 - Cinematography - specifies the lateral (and where applicable vertical) positions and width dimensions of multichannel analogue and digital photographic sound records and control tracks on 35 mm motion‑picture prints and negatives, and of digital sound‑control records on 70 mm film. The standard defines precise placement and sizing so sound and control data on film are interoperable across printing, scanning, playback and archiving workflows.
Key topics and requirements
- Scope: Lateral and vertical placement and width dimensions for analogue sound tracks, digital sound records (Type I and II) and digital control tracks (Type III) on 35 mm and 70 mm film.
- Track types:
- Type I - interperforation digital sound (print and negative dimensions given).
- Type II - outerperforation digital sound (print and negative dimensions given).
- Type III - digital control track (35 mm and 70 mm variants).
- Illustrations and tables: Positions and tolerances are shown in Figure 1–7 and specified in Table 1–9, covering print vs negative, and 35 mm vs 70 mm requirements.
- Representative dimensions (from the standard):
- Analogue channel centres: Channel 1 (Lt) at 6.72 mm and Channel 2 (Rt) at 5.63 mm from the reference edge.
- Type I digital (print) example: W = 2.41 mm, X = 0.160 ± 0.076 mm, Y = 2.185 ± 0.076 mm, Z = 2.77 mm (see Tables 2–3).
- Type III (35 mm print) control track examples: A ≈ 7.584 mm, B ≈ 0.076–0.152 mm (see Tables 6–7).
(Refer to ISO 17266:2018 for full dimensional tables and tolerances.)
- Analogue specifics: Two‑channel analogue tracks are aligned at 90° ± 5′ to the film reference edge; channel 2 is nearest the outer edge and the septum between channels must be effectively opaque on prints.
Applications and users
- Film laboratories and printers: Ensure accurate placement of analogue/digital audio and control tracks for reliable duplication and printing (35 mm ↔ 70 mm workflows).
- Post‑production and sound departments: Match audio deliverables to camera negatives and print specifications for theatrical distribution.
- Archiving and restoration: Confirm original track geometry for preservation, scanning and transfer.
- Equipment manufacturers: Design scanners, readers, printers and projectors that align with standard track positions and widths.
- Standards bodies and quality control teams: Use the normative tables/figures for conformance testing and production QA.
Related standards
- ISO 17266:2018 references previous industry standards and lists ISO 7343:1993 (two‑track photographic sound on 35 mm) in its bibliography. For terminologies consult the ISO Online Browsing Platform.
Keywords: ISO 17266:2018, cinematography standard, 35 mm sound tracks, 70 mm control track, multichannel analogue digital sound, film track dimensions, film printing specifications.