Overview
ISO 3026:1992 specifies the position and dimensions of the printed 8 mm Type S image area when produced by optical or contact printing onto 35 mm motion‑picture film perforated 8 mm Type S (pitch variants 2R-4.227 (1664) or 5R-4.234 (1667)). The standard defines how the image area is located relative to a row of perforations that is discarded after slitting; this discarded row contains a wider perforation customarily used for lateral registration. Annex A gives informative guidance on using a registration (stop) device for prints made with step printers.
Key topics and technical requirements
- Scope: Applies to negative, intermediate or positive prints produced on 35 mm film perforated 8 mm Type S.
- Image referencing: Image dimensions and positions are referenced to the row of perforations removed after slitting; this ensures consistent lateral registration.
- Registration spacing: A reference lateral registration dimension of 7.9 mm (0.311 in) is used, measured between the positioning perforation and the horizontal axis of the produced 8 mm image.
- Dimension set: The standard provides a table (Table 1) and figure defining dimensional callouts (A–L and R) in both metric and inch units for accurate printing and verification.
- Projector alignment: The vertical reference (cote H) is tied to “perforation minus 2” because that perforation aligns with the projector positioning used for direct front projection (see ISO 1781).
- Informative annexes: Annex A - use of stop devices on alternative printers; Annex B - bibliographic references.
Practical applications and users
ISO 3026:1992 is intended for professionals and organizations involved in film production, printing and archiving, including:
- Film laboratories performing optical contact or step printing of 8 mm Type S images onto 35 mm stock
- Post‑production and finishing houses ensuring printed frames meet positional tolerances
- Equipment designers (tireuses, step printers, registration devices) and projector manufacturers needing compatibility with projector positioning standards
- Film restorers and archives validating historic prints and remastering workflows
- Quality assurance and standards compliance teams implementing consistent image registration across prints
Using ISO 3026 helps ensure consistent image placement, reliable lateral registration, and projector compatibility - essential for projection, duplication and long‑term preservation of 8 mm Type S material.
Related standards
Informative references listed in the standard include:
Keywords: ISO 3026, 8 mm Type S, 35 mm film, image area, film perforations, position and dimensions, film printing, registration device.