ISO 21550-2004 PDF

Full title and description

ISO 21550:2004 — Photography — Electronic scanners for photographic images — Dynamic range measurements. This International Standard gives methods for measuring and reporting the dynamic range capability of electronic scanners used to capture continuous‑tone photographic media (both reflective and transmissive types).

Abstract

Specifies procedures, test targets and measurement methods to determine and report the dynamic range of electronic scanners for photographic images. The procedures apply to scanners for reflective media (prints) and transmissive media (film, transparencies) and describe how to obtain repeatable, comparable dynamic‑range figures for performance assessment and specification.

General information

• Status: Published; International Standard (confirmed on systematic review).
• Publication date: October 2004 (2004‑10).
• Publisher: International Organization for Standardization (ISO).
• ICS / categories: 37.040.10 (Photographic equipment, projectors).
• Edition / version: Edition 1 (2004).
• Number of pages: 14.

Key bibliographic and status details are recorded in the ISO bibliographic entry for ISO 21550:2004.

Scope

Applies to measurement of the dynamic range of electronic scanners intended to digitize continuous‑tone photographic originals. It covers both reflective and transmissive scanners and outlines required test targets, measurement geometry and procedures for deriving a dynamic‑range value that can be reported and compared between instruments. The standard is focused on tonal range measurement for photographic reproduction rather than on colourimetric or geometric performance.

Key topics and requirements

• Definitions and terminology for dynamic range in the context of photographic scanners.
• Specification of test targets and sample preparation for reflective and transmissive media.
• Measurement setup, including illumination, scanner settings and measurement geometry.
• Procedure to acquire data and calculate dynamic‑range metrics (signal limits, noise floor, usable tonal range).
• Reporting conventions and required information to accompany dynamic‑range results for comparability.
• Requirements for repeatability and conditions under which measurements should be made.

Typical use and users

Used by scanner manufacturers, test laboratories, imaging and archiving professionals, museums and cultural‑heritage digitization projects, and purchasers specifying scanner performance. It is employed for product specification, quality control, acceptance testing and comparative performance evaluation.

Related standards

ISO 21550 sits within the photography/imaging standards ecosystem. Commonly referenced or complementary standards include ISO 12233 (resolution and spatial-frequency measurements for electronic imaging), ISO 12232 (exposure index and sensitivity for electronic still picture imaging), ISO 15739 (noise and dynamic range for electronic still-picture imaging), ISO 14524 (tone‑reproduction/OECF methods) and viewing‑conditions standards such as ISO 3664. These documents address other image quality attributes (resolution, noise, tone response and viewing conditions) that complement dynamic‑range testing.

Keywords

dynamic range, scanner, photographic scanner, transmissive, reflective, continuous‑tone, measurement, test target, image quality, ISO 21550.

FAQ

Q: What is this standard?

A: ISO 21550:2004 is an ISO International Standard that specifies methods for measuring and reporting the dynamic range of electronic scanners used to digitize continuous‑tone photographic media (prints, negatives, transparencies).

Q: What does it cover?

A: It covers test targets, measurement setup and procedures, calculation of dynamic‑range metrics, and reporting requirements so results are repeatable and comparable across scanners and laboratories. It applies to both reflective and transmissive scanners.

Q: Who typically uses it?

A: Scanner manufacturers, independent test and calibration laboratories, imaging engineers, archive and museum digitization teams, and procurement/specification authors use this standard for product testing, conformance checks and performance comparison.

Q: Is it current or superseded?

A: ISO 21550:2004 was published in October 2004 and, according to the ISO bibliographic record, has been subject to periodic systematic review and was confirmed as the current edition during reviews (most recently recorded as confirmed in 2022). It is not shown as withdrawn or superseded in the ISO record.

Q: Is it part of a series?

A: ISO 21550 is a standalone International Standard focused on dynamic‑range measurement for photographic scanners. It is one of several ISO documents addressing image quality and photographic imaging produced under ISO/TC 42 (Photography), and is commonly used alongside related imaging standards rather than as a numbered multi‑part series.

Q: What are the key keywords?

A: Dynamic range; photographic scanner; transmissive scanner; reflective scanner; measurement procedure; test target; image quality; ISO 21550.