ISO 8758:1992

Overview

ISO 8758:1992 defines the dimensions and lateral location of photographic control and data records on 16 mm and 35 mm motion-picture film (originals, intermediates and prints). The standard also specifies the scanned width used by control-data reproducers and the reproducer spectral sensitivity required to ensure reliable reading of control tracks across dye and silver film systems. For release prints, ISO 8758 applies only to those containing variable area sound records in accordance with ISO 2939 and ISO 7343.

Key topics and technical requirements

• Precise placement and dimensions: The standard provides figures and tables showing the exact lateral location and size tolerances for control and data tracks on 16 mm and 35 mm film and prints. Example values (given to ±0.03 mm) include:
  • 35 mm release-print lateral values around 7.42 mm to 7.67 mm from the reference edge.
  • 16 mm film lateral values around 15.54 mm to 15.95 mm from the reference edge.
• Scanned width: ISO 8758 specifies the width that a control-data reproducer must scan (shown in the standard’s figures) to reliably capture the data track.
• Reproducer spectral sensitivity:
  • Peak response of the light source/filter/receptor combination must be at 550 nm.
  • Integrated response for wavelengths > 800 nm must be < 5% of the integrated response measured from 400–800 nm.
• Practical alignment guidance: Informative annex notes emphasize careful printer and projector alignment to avoid misprinting or projecting data tracks over control records and to preserve signal-to-noise when dyes and dirt can affect infrared response.

Applications and users

ISO 8758 is used to ensure compatibility and reliable operation across the cinematography ecosystem:

• Film camera and aperture designers (to position control tracks)
• Post-production and printing laboratories (to align printers and reproducers)
• Projectionists and theatres (to avoid projecting data tracks)
• Archive and restoration specialists and digitization facilities (to read and preserve metadata)
• Manufacturers of control-data reproducers and audio/sound record equipment

Adhering to ISO 8758 helps maintain consistent placement of metadata/control tracks and reliable reading across different film stocks, improving interoperability for workflows involving analog film, sound tracks, and film-to-digital transfers.

Related standards

• ISO 2939:1986 - Picture image area and photographic sound record on 35 mm motion-picture release prints.
• ISO 7343:1983 - Two-track photographic sound records on 35 mm motion-picture prints (positions and width).