ISO 18909-2022 PDF

Full title and description

Photography — Processed photographic colour films and paper prints — Methods for measuring image stability. This international standard specifies laboratory test methods for assessing the long‑term dark‑storage stability and the colour stability of processed photographic colour films and reflection prints when exposed to specified illuminants, temperatures and relative humidities.

Abstract

This document describes test methods for determining the long‑term dark storage stability of colour photographic images and the colour stability of such images when subjected to specific illuminants at specified temperatures and relative humidities. It applies to traditional continuous‑tone photographic materials with images formed with dyes (chromogenic, silver dye‑bleach, dye transfer and dye‑diffusion‑transfer instant systems), and notes systems for which the tests have not been verified. The document does not include procedures for physical stability of supports or binder materials.

General information

• Status: Published
• Publication date: 15 February 2022
• Publisher: International Organization for Standardization (ISO)
• ICS / categories: 37.040.20 (Photographic paper, films and plates)
• Edition / version: Edition 2 (2022)
• Number of pages: 50

Scope

Specifies laboratory methods to evaluate: (a) long‑term dark‑storage stability of processed colour photographic images; and (b) colour stability when images are exposed to specified lighting conditions, temperatures and relative humidities. Applicable to dye‑based, continuous‑tone traditional photographic systems including chromogenic, silver dye‑bleach, dye transfer and dye‑diffusion‑transfer instant systems. The standard states the tests have not been verified for many digitally produced or non‑dye systems (for example dry/liquid toner electrophotography, thermal dye transfer/dye sublimation, ink‑jet and certain pigment systems) and excludes test procedures for physical deterioration of supports or binders. It cross‑references other ISO documents for digital printing stability testing and for light‑stability tests.

Key topics and requirements

• Defined accelerated ageing protocols for dark‑storage stability testing (controlled temperature and relative humidity).
• Specified light‑exposure tests for evaluating colour stability under defined illuminants and environmental conditions.
• Applicability limited to traditional, dye‑based photographic systems (chromogenic, silver dye‑bleach, dye transfer, dye‑diffusion instant).
• Explicit exclusions for many digital and toner‑based imaging processes; pointers to the ISO 1893x/18937 series for those methods.
• Emphasis on measurement reproducibility and reporting of colour change (test conditions, specimen preparation and environmental controls).
• Does not provide procedures for assessing physical support or binder degradation (e.g., embrittlement, cracking, delamination).

Typical use and users

Used by photographic materials manufacturers, analytical and materials testing laboratories, conservation scientists, archives and museums concerned with preservation of colour film and print collections, and standards/quality managers establishing material specifications and shelf‑life claims.

Related standards

The standard itself refers users to related ISO work for digitally produced reflection prints and for light‑stability testing, in particular ISO 18936, ISO 18941, ISO 18946, ISO 18949 (dark stability of certain printed reflection materials) and the ISO 18937 series (light stability). It replaces the earlier ISO 18909:2006 edition.

Keywords

image stability, lightfastness, dark‑storage stability, colour photographic prints, chromogenic, dye transfer, dye‑diffusion transfer, accelerated ageing, ISO 18909

FAQ

Q: What is this standard?

A: An ISO international standard that defines laboratory methods for measuring the image stability (dark‑storage and light‑exposed colour stability) of processed photographic colour films and paper prints.

Q: What does it cover?

A: Laboratory test procedures for assessing long‑term dark storage stability and colour stability under specified illuminants, temperatures and relative humidities for traditional dye‑based photographic systems; it does not cover physical support degradation tests and excludes many digital/toner printing processes.

Q: Who typically uses it?

A: Manufacturers of photographic films and papers, materials testing labs, conservation departments, archives, museums and standards/quality professionals.

Q: Is it current or superseded?

A: Current — ISO 18909:2022 (Edition 2) was published 15 February 2022 and supersedes ISO 18909:2006.

Q: Is it part of a series?

A: It is related by subject to other ISO standards addressing stability of printed reflection materials and light‑stability testing (notably the ISO 1893x and ISO 18937 series referenced in the standard), but it is a standalone document focused on processed photographic colour films and prints.

Q: What are the key keywords?

A: image stability; dark storage; lightfastness; colour photographs; chromogenic; dye transfer; accelerated ageing; ISO 18909.