ASTM E259-98

Standard Practice for Preparation of Pressed Powder White Reflectance Factor Transfer Standards for Hemispherical Geometry and Bi-Directional Geometries

SCOPE
1.1 This practice covers procedures for preparing pressed powder transfer standards of reflectance factor. These standards can be used in the near-ultraviolet, visible and near-infrared region of the spectrum. Procedures for calibrating the reflectance factor of materials on an absolute basis are contained in CIE Publication No. 44 (2). Pressed powder standards are used as transfer standards for such calibrations because they have a high reflectance factor which is nearly constant with wavelength and because the distribution of reflected flux resembles that from the perfect reflecting diffuser.
1.2 This standard does not purport to address all of the safety problems, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.  
1.3 The values stated in SI units are to be regarded as the standard. The values in parentheses are for information only.

General Information

• Status: Historical
• Publication Date: 09-Oct-1998
• Technical Committee: E12 - Color and Appearance
• Drafting Committee: E12.02 - Spectrophotometry and Colorimetry

Relations

• Replaced By: ASTM E259-98(2003) - Standard Practice for Preparation of Pressed Powder White Reflectance Factor Transfer Standards for Hemispherical and Bi-Directional Geometries
• Effective Date: 10-Jul-2003

Standards Content (Sample)

NOTICE: This standard has either been superseded and replaced by a new version or withdrawn. Contact
ASTM International (www.astm.org) for the latest information.
Designation: E 259 – 98
AMERICAN SOCIETY FOR TESTING AND MATERIALS
100 Barr Harbor Dr., West Conshohocken, PA 19428
Reprinted from the Annual Book of ASTM Standards. Copyright ASTM
Standard Practice for
Preparation of Pressed Powder White Reflectance Factor
Transfer Standards for Hemispherical and Bi-Directional
1
Geometries
This standard is issued under the fixed designation E 259; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (e) indicates an editorial change since the last revision or reapproval.
INTRODUCTION
The internationally accepted standard of reflectance is the perfect reflecting diffuser. This ideal
reflecting surface reflects 100 % of the incident radiant power such that the radiance is the same for
all directions within the hemisphere above the surface. No physical realization of this standard exists.
Optical properties of standards prepared from pressed plaques of magnesium carbonate (MgCO ),
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barium sulfate (BaSO ), or polytetrafluoroethylene (PTFE) can approximate an ideal standard. For
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2
further information see CIE Publication No. 46 (1). The principal use of a white reflectance factor
standard is to transfer an absolute scale of reflectance to a more durable material or from one
instrument to another. In theory, it should be easy to do this transfer from first principles. In practice,
one is likely to need values for parameters that are unknown, proprietary, or require a high level of
skill. Some, but not all, of those parameters are discussed in this practice.
1. Scope 2. Referenced Documents
1.1 This practice covers procedures for preparing pressed 2.1 ASTM Standards:
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powder transfer standards. These standards can be used in the E 284 Terminology of Appearance
near-ultraviolet, visible and near-infrared region of the electro-
3. Terminology
magnetic spectrum. Procedures for calibrating the reflectance
3.1 Terms and definitions in Terminology E 284 are appli-
factor of materials on an absolute basis are contained in CIE
Publication No. 44 (2). Pressed powder standards are used as cable to this practice.
3.2 Definitions—The following definitions are particularly
transfer standards for such calibrations because they have a
high reflectance factor that is nearly constant with wavelength, important to this practice:
3.2.1 perfect reflecting diffuser—ideal reflecting surface that
and because the geometric distribution of reflected flux re-
sembles that from the perfect reflecting diffuser. neither absorbs nor transmits light, but reflects diffusely, with
the radiance of the reflecting surface being the same for all
1.2 The values stated in SI units are to be regarded as the
standard. The values in parentheses are for information only. reflecting angles, regardless of the angular distribution of the
incident light. (1990)
1.3 This standard does not purport to address all of the
safety concerns, if any, associated with its use. It is the 3.2.2 reflectance, r, n—ratio of the reflected radiant or
luminous flux to the incident flux in the given conditions.
responsibility of the user of this standard to establish appro-
A
priate safety and health practices and determine the applica- [CIE]
3.2.3 The term reflectance is often used in a general sense or
bility of regulatory limitations prior to use.
as an abbreviation for reflectance factor. Such usage may be
assumed unless the above definition is specifically required by
the context. (1989b)
1
This practice is under the jurisdiction of ASTM Committee E-12 on Color and
3.2.4 reflectance factor, R, n—ratio of the flux reflected
Appearance and is the direct responsibility of Subcommittee E12.02 on Spectro-
from the specimen to the flux reflected from the perfect
photometry and Colorimetry.
reflecting diffuser under the same geometric and spectral
Current edition approved Oct. 10, 1998. Published March 1999. Originally
B
published as E 259 – 65. Last previous edition E 259 – 97.
conditions of measurement. [CIE] (1988)
2
The boldface numbers in parentheses refer to the list of references at the end of
this practice.
4. Summary of Practice
4.1 Procedures are given for the preparation of white
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Annual Book of ASTM Standards, Vol 06.01.
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NOTICE:¬This¬standard¬has¬either¬been¬superceded¬and¬replaced¬by¬a¬new¬version¬or¬discontinued.¬
Contact¬ASTM¬International¬(www.astm.org)¬for¬the¬latest¬information.¬
E 259
6. Apparatus
6.1 The basic apparatus for producing a pressed powder
standard includes a powder press, powder containers and a
balance. There are presently two commercial suppliers of
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powder presses. The press and receptacles can also be made in
a local machine shop. A suggested config
...