ISO 2907:2002

Overview

ISO 2907:2002 - Cinematography - specifies the maximum projectable image area on 35 mm motion‑picture film, defining both the position and dimensions of that area relative to the film perforations and the film’s reference edge. The standard covers three theatrical projection styles: Style A (non‑anamorphic / widescreen), Style B (anamorphic), and Style C (classic theatrical). It is intended for use in designing and specifying camera, printing and projection workflows that involve 35 mm release prints.

Key topics and technical requirements

• Projectable image dimensions and placement: The standard gives precise linear dimensions for the projectable image area. For example, A = 20.95 mm (common image width); B varies by style (Style A: 11.32 mm min to 12.70 mm max; Style B: 17.53 mm max; Style C: 15.29 mm nominal). Other parameters include D (8.23 mm min) and E (29.24 mm max).
• Reference edge and perforation alignment: Image area position is specified relative to the film reference edge and sprocket perforations to ensure consistent registration and image steadiness. The image centreline is displaced by 1.27 mm nominal from the film centreline (see Annex A.1).
• Projectable area vs. aperture plate: ISO 2907 defines the maximum image on film available for projection - it does not mandate the physical aperture‑plate opening, which may be smaller because of mechanical clearance, lens acceptance angle, or to avoid film scratching.
• Aspect ratios and framing guidance: Typical non‑anamorphic aspect ratios and associated image heights are given (for example Style A 1.85:1 - 11.32 mm min; 1.66:1 - 12.62 mm ref; Style C 1.37:1 - 15.29 mm nominal). The standard notes the use of hard mattes for consistent vertical centring.
• Practical tolerances and caveats: The document recognizes that actual projected images can be smaller or non‑rectangular due to equipment, geometric, or aesthetic reasons and states that projected image should normally be the largest appropriately shaped figure inscribed within the specified limits.

Applications and users

• Projection equipment manufacturers: lens and aperture‑plate design, mechanical film guides and steadiness features.
• Film laboratories and printers: setting print image areas and hard mattes for theatrical release prints.
• Cinematographers and post‑production: compose and crop images knowing the maximum projectable area and recommended aspect ratios.
• Theatre exhibitors and projectionists: alignment, masking and framing of projected pictures to conform with release print standards.
• Archives and restoration labs: conservation and re‑projection of 35 mm materials while maintaining original framing intent.

Related standards

• ISO 2906:2002 - Image area produced by camera aperture on 35 mm film
• ISO 23, ISO 2939, ISO 4241 - complementary film and projection specifications
• SMPTE standards (e.g., SMPTE 195) - related motion‑picture film projectable image area practices

Keywords: ISO 2907:2002, 35 mm motion‑picture film, projectable image area, cinematography, aspect ratio, anamorphic, projection aperture, film perforations, reference edge.