1、Designation: E883 11 (Reapproved 2017)Standard Guide forReflectedLight Photomicrography1This standard is issued under the fixed designation E883; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision. A number i
2、n parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.This standard has been approved for use by agencies of the U.S. Department of Defense.1. Scope*1.1 This guide outlines various methods which may befollowed
3、 in the photography of metals and materials with thereflected-light microscope. Methods are included for prepara-tion of prints and transparencies in black-and-white and incolor, using both direct rapid and wet processes.1.2 Guidelines are suggested to yield photomicrographs oftypical subjects and,
4、to the extent possible, of atypical subjectsas well. Information is included concerning techniques for theenhanced display of specific material features. Descriptivematerial is provided where necessary to clarify procedures.References are cited where detailed descriptions may behelpful.1.3 This stan
5、dard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory requirements prior to use. Specific precau-tionary st
6、atements are given in X1.7.1.4 The sections appear in the following order:Referenced documents 2Terminology 3Significance and use 4Magnification 5Reproduction of photomicrographs 6Optical systems 7Illumination sources 8Illumination of specimens 9Focusing 10Filters for photomicrography 11Illumination
7、 techniques 12Instant-processing films 13Photographic materials 14Photographic exposure 15Photographic processing 16Keywords 17Suggestions for visual use of metallographicmicroscopesAppendixX1Guide for metallographic photomacrography AppendixX2Electronic photography AppendixX31.5 This international
8、standard was developed in accor-dance with internationally recognized principles on standard-ization established in the Decision on Principles for theDevelopment of International Standards, Guides and Recom-mendations issued by the World Trade Organization TechnicalBarriers to Trade (TBT) Committee.
9、2. Referenced Documents2.1 ASTM Standards:2E7 Terminology Relating to MetallographyE175 Terminology of MicroscopyE768 Guide for Preparing and Evaluating Specimens forAutomatic Inclusion Assessment of SteelE1951 Guide for Calibrating Reticles and Light MicroscopeMagnifications2.2 Other Standard:3MSDS
10、 Mercury-Material Safety Data Sheet3. Terminology3.1 DefinitionsFor definitions of terms used in this guide,see Terminologies E7 and E175.4. Significance and Use4.1 This guide is useful for the photomicrography andphotomacrography of metals and other materials.4.2 The subsequent processing of the ph
11、otographic materi-als is also treated.5. Magnification5.1 Photomicrographs shall be made at preferredmagnifications, except in those special cases where details ofthe microstructure are best revealed by unique magnifications.1This guide is under the jurisdiction of ASTM Committee E04 on Metallogra-p
12、hyand is the direct responsibility of Subcommittee E04.03 on Light Microscopy.Current edition approved June 1, 2017. Published June 2017. Originallyapproved in 1982. Last previous edition approved in 2011 as E883 11. DOI:10.1520/E0883-11R17.2For referenced ASTM standards, visit the ASTM website, www
13、.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3Available from United States Environmental ProtectionAgency (EPA),WilliamJefferson Clinton Bldg., 1200 Pennsylvania Ave
14、., NW, Washington, DC 20460,http:/www.epa.gov.*A Summary of Changes section appears at the end of this standardCopyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United StatesThis international standard was developed in accordance with internationally
15、 recognized principles on standardization established in the Decision on Principles for theDevelopment of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.15.2 The preferred magnifications for photomicrographs, are
16、:25, 50, 75, 100, 200, 250, 400, 500, 750, 800,and 1000.5.3 Magnifications are normally calibrated using a stagemicrometer. Calibration procedures in Guide E1951 should befollowed.6. Reproduction of Photomicrographs6.1 Photomicrographs should be at one of the preferredmagnifications. A milli- or mic
17、rometre marker shall be super-imposed on the photomicrograph to indicate magnification, ina contrasting tone. The published magnification, if known,should be stated in the caption.6.2 Photomicrograph captions should include basic back-ground information (for example, material identification,etchant,
18、 mechanical or thermal treatment details) and shouldbriefly describe what is illustrated so that the photomicrographcan stand independent of the text.6.3 Arrows or other markings, in a contrasting tone, shall beused to designate specific features in a photomicrograph. Anymarking used shall be refere
19、nced in the caption.7. Optical Systems7.1 Microscope objectives are available in increasing orderof correction as achromats, semiapochromats (fluorites) andapochromats (see Terminologies E7 and E175). Plan objectivesare recommended for photographic purposes because theircorrection provides a flatter
20、 image. The objective lens forms animage of the specimen in a specific plane behind the objectivecalled the back focal plane. (This is one of several possible realimage planes, called intermediary planes, where reticles maybe inserted as optical overlays on the image.)7.2 The eyepiece magnifies the
21、back focal plane (or other)intermediary image for observation or photomicrography. Eye-pieces are sometimes also used to accomplish the full correc-tion of the objectives spherical aberration and to improve theflatness of field.7.2.1 The pupil of the observers eye must be brought tocoincidence with
22、the eyepoint of the visual eyepiece to viewthe entire microscopical image. High-eyepoint eyepieces arenecessary for eyeglass users to see the entire image field.7.2.2 Most microscopes have built-in photographic capa-bilities that use an alternate image path through the microscopeleading to a camera
23、attachment port or to a viewscreen. Aprojection eyepiece delivers the image to the camera port orscreen.7.3 Intermediate lenses (relay or tube lenses) are oftenrequired to transfer the specimen image from the intermediaryplane of the objective to that of the eyepiece. They may alsoadd their own magn
24、ification factor, either fixed or as a zoomsystem.7.4 The objective, the eyepiece, and the compound micro-scope (including any intermediate lenses) are designed as asingle optical unit. It is recommended to use only objectivesand eyepieces which are intended for the microscope in use.7.5 The resolut
25、ion of the microscope depends primarily onthe numerical aperture of the objective in use (1)4. The termempty magnification is used to describe high magnifications(above approximately 1100 times the numerical aperture of anobjective), which have been shown to offer no increase inimage resolution. Nev
26、ertheless, some types of information,such as the distance between two constituents, may be moreeasily obtained from microstructures examined at moderateempty magnifications.8. Illumination Sources8.1 Metallographic photomicrography typically uses Khlerillumination. To obtain Khler illumination, an i
27、mage of thefield diaphragm is focused in the specimen plane, and an imageof the lamp filament or arc is focused in the plane of theaperture diaphragm. Specific steps to obtain Khler illumina-tion vary with the microscope used. The manufacturersinstructions should be followed closely.8.2 For incandes
28、cent lamps, the applied voltage determinesthe unit brightness and the color temperature of the source.Evaporated tungsten blackens the envelope, resulting in dimin-ished brightness and color temperature as the lamp ages.Tungsten-halogen lamps minimize envelope blackening, main-taining constant brigh
29、tness and color temperature for most oftheir life. The high brightness and 3200 K color temperature ofthese lamps makes them especially suitable for color photomi-crography.8.3 With arc sources, brightness per unit area is substan-tially higher than that from any incandescent source. Theirspectral o
30、utput contains high energy spikes superimposed on awhite-light continuum. They also contain significant ultraviolet(UV) and infrared (IR) emissions that should be removed foreye safety (and for photographic consistency, with UV); see8.4, 11.3.1, and 11.5.2.8.3.1 Xenon arcs produce a spectral quality
31、 close to daylight(5600K), with a strong spike at 462 nm. Strong emissions inthe IR should be removed. Xenon arcs that do not produceozone are recommended.8.3.2 Carbon arcs have a continuous output in the visibleportion of the spectrum, with a color temperature near 3800Kand a strong emission line a
32、t 386 nm.8.3.3 Mercury arcs have strong UV and near-UV output,and are particularly useful to obtain maximum resolution witha blue filter. The color quality is deficient in red; it cannot bebalanced for color photomicrography. WarningMercury hasbeen designated by EPA and many state agencies as a haza
33、rd-ous material that can cause central nervous system, kidney, andliver damage. Mercury, or its vapor, may be hazardous tohealth and corrosive to materials. Caution should be takenwhen handling mercury and mercury-containing products. Seethe applicable product Material Safety Data Sheet (MSDS) forde
34、tails and EPAs website (http:/www.epa.gov/mercury/faq.htm) for additional information. Users should be aware thatselling mercury or mercury-containing products, or both, inyour state may be prohibited by state law.4The boldface numbers in parentheses refer to the list of references at the end ofthis
35、 standard.E883 11 (2017)28.3.4 Zirconium arcs have strong spectral output lines in thenear IR, requiring filtration. Within the visible region, they arerated at 3200K color temperature.8.4 Arc lamps require heat protection for filters and otheroptical components, and certainly for eye safety. Infrar
36、edremoval may be obtained by: “hot” mirrors in the illuminationbeam to reflect IR while transmitting visible light; heat-absorbing filters to transmit visible light while absorbing IR,for example, solid glass filters or liquid-filled cells.8.5 A detailed discussion of illumination sources and thequa
37、lity of illuminants is given by Loveland (2).8.6 Some advice on using metallographic microscopes forvisual observation has been compiled in Appendix X1.9. Illumination of Specimens9.1 Photomicrographs are made with a compound micro-scope comprised at least of an objective lens and an eyepiecewith a
38、vertical illuminator between them. Field and aperturediaphragms, with a lamp and lamp condenser lenses, areintegral parts of the system. The microscope should allowsufficient adjustment to illuminate the field of view evenly andto completely fill the back aperture of the objective lens withlight.9.2
39、 The vertical illuminator is a thin-film-coated plane glassreflector set at 45 to the optical axis behind the objective. Itreflects the illumination beam into the objective and transmitsthe image beam from the objective to the eyepiece. In somemicroscopes prism systems are used to perform this funct
40、ion.9.3 The field diaphragm is an adjustable aperture whichrestricts the illuminated area of the specimen to that which is tobe photographed. It eliminates contrast-reducing stray light.The field diaphragm is also a useful target when focusing alow-contrast specimen.9.4 The aperture diaphragm establ
41、ishes the optimum bal-ance between contrast, resolution, and depth of field. It shouldbe set to illuminate about 70 % of the objectives aperturediameter. This can be observed by removing the eyepiece andinspecting the back of the objective, either directly or with apinhole eyepiece. The aperture dia
42、phragm should never beused as a light intensity control.9.5 See Fig. 1 for an illustration of a typical verticalillumination system.10. Focusing10.1 Sharp focus is necessary to obtain good photomicro-graphs.10.2 There are two systems for obtaining sharp focus:ground-glass focusing and aerial image f
43、ocusing.10.2.1 For ground-glass focusing, relatively glare-free sur-roundings and a magnifier up to about 3 are required. Tofocus, the focusing knob is oscillated between underfocus andoverfocus in succeedingly smaller increments until the image issharp.10.2.2 There are four possible variations for
44、focusing anaerial image.10.2.2.1 The simplest case is a transparent spot on aground-glass containing a fiduciary mark in the film plane. Thespecimen image is focused to coincide with the fiduciary mark,using a magnifying loupe of about 3 to 5. When the focus iscorrect, the specimen image and the fid
45、uciary mark will notmove with respect to each other when the operators head ismoved.10.2.2.2 Asecond case uses a reticle fixed within the opticalsystem at an intermediary plane. Focusing is a two-stepprocess: focus the eyepiece on the reticle; bring the image intofocus against the reticle figure.10.
46、2.2.3 In the third case, a reticle is inserted into a focusingeyepiece. Depending on equipment used, this can be either atwo or three-step process: focus the reticle within the eyepiece;next, set the proper interpupiliary distance, if required (someequipment requires a specific interpupiliary distan
47、ce for eye-piece focus to coincide with camera focus); then focus theimage coincident with the reticle.FIG. 1 Vertical Illuminating System for a Metallurgical MicroscopeE883 11 (2017)310.2.2.4 The fourth case uses a single-lens reflex camerabody, where the camera focusing screen is the plane ofrefer
48、ence. An eyepiece magnifier for the camera is an impor-tant accessory for this case. An aerial image focusing screen ispreferred.10.3 The critical focus point is affected by both the principalillumination wavelength in use and the size of the aperturediaphragm. Final focusing should be checked with
49、all filters,apertures, and other components set for the photomicrograph.11. Filters for Photomicrography11.1 Photomicrographs require filtration of the light source.This section describes filter types and their uses.11.2 Each filter selectively removes some wavelengths fromthe transmitted beam of light. Two types of filters, interferenceand absorption, can be used for this purpose.11.2.1 Interference filters act as selective mirrors. By meansof coatings on a glass substrate, they selectively transmitcertain wavelengths while reflecting all others. Thes
