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    ASTM E1951 - 14(2019)

    Standard Guide for Calibrating Reticles and Light Microscope Magnifications

    Active Standard ASTM E1951 | Developed by Subcommittee: E04.03

    Book of Standards Volume: 03.01


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    Significance and Use

    4.1 These methods can be used to determine magnifications as viewed through the eyepieces of light microscopes.

    4.2 These methods can be used to calibrate microscope magnifications for photography, video systems, and projection stations.

    4.3 Reticles may be calibrated as independent articles and as components of a microscope system.

    1. Scope

    1.1 This guide covers methods for calculating and calibrating microscope magnifications, photographic magnifications, video monitor magnifications, grain size comparison reticles, and other measuring reticles. Reflected light microscopes are used to characterize material microstructures. Many materials engineering decisions may be based on qualitative and quantitative analyses of a microstructure. It is essential that microscope magnifications and reticle dimensions be accurate.

    1.2 The calibration using these methods is only as precise as the measuring devices used. It is recommended that the stage micrometer or scale used in the calibration should be traceable to the National Institute of Standards and Technology (NIST) or a similar organization.

    1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.

    1.4 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.


    2. Referenced Documents (purchase separately) The documents listed below are referenced within the subject standard but are not provided as part of the standard.

    ASTM Standards

    E7 Terminology Relating to Metallography

    E112 Test Methods for Determining Average Grain Size


    ICS Code

    ICS Number Code 37.020 (Optical equipment)

    UNSPSC Code

    UNSPSC Code 41111700(Viewing and observing instruments and accessories)


    Referencing This Standard
    Link Here
    Link to Active (This link will always route to the current Active version of the standard.)

    DOI: 10.1520/E1951-14R19

    Citation Format

    ASTM E1951-14(2019), Standard Guide for Calibrating Reticles and Light Microscope Magnifications, ASTM International, West Conshohocken, PA, 2019, www.astm.org

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