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1、ANSUISO 7829-1986, ANSUNAPM ll2.4-1987 for Photography (Sensitometry) - Black-and- White Aerial Camera Films - Determination of IS0 Speed and Average Gradient American National Standards Institute + ANSI/IS0 7829-l 986(R1996) ANWNAPM IT2.4-1987(R1997) Reaffirmation and redesignation of ANSI/IS0 7829

2、-1986, ANSI PH2.34-1987 American National Standard for Photography (Sensitometry) - Black-and-White Aerial Camera Films - Determination of IS0 Speed and Average Gradient Secretariat National Association of Photographic Manufacturers Approved May 28, 1987 Reaffirmation approved January 24, 1997 Ameri

3、can National Standards Institute, Inc. American PP A roval of an American National Standard requires verification by ANSI that the requirements for due process, consensus, and other criteria for National aw roval have been met by the standards developer. Standard c onsensus is established when, in t

4、he judgment of the ANSI Board of Standards Review, substantial agreement has been reached by directly and materially affected interests. Substantial agreement means much more than a simple majority, but not necessarily unanimity. Consensus requires that all views and objections be considered, and th

5、at a concerted effort be made toward their resolution. The use of American National Standards is completely voluntary; their existence does not in any respect preclude anyone, whether he has approved the standards or not, from manufacturing, marketing, purchasing, or using products, processes, or pr

6、ocedures not conforming to the standards. The American National Standards institute does not develop standards and will in no circumstances give an interpretation of any American National Standard. Moreover, no person shall have the right or authority to issue an interpretation of an American Nation

7、al Standard in the name of the American National Standards Institute. Requests for interpretations should be ad- dressed to the secretariat or sponsor whose name appears on the title page of this standard. CAUTION NOTICE: This American National Standard may be revised or withdrawn at any time. The p

8、rocedures of the American National Standards Institute require that action be taken periodically to reaffirm, revise, or withdraw this standard. Purchasers of American National Standards may receive current information on all standards by calling or writing the American National Standards Institute.

9、 Published by American National Standards Institute 11 West 42nd Street, New York, New York 10036 Copyright 01987 by American National Standards Institute All rights reserved. No part of this publication may be reproduced in any form, in an electronic retrieval system or otherwise, without prior wri

10、tten permission of the publisher. Printed in the United States of America Foreword (This Foreword isnot part of American National Standard ANSI/IS0 7829-1986, ANSI PH2.34-1987.) The International Organization for Standardization (ISO) is a worldwide federation of national standards institutes (IS0 m

11、ember bodies) that develops and publishes Interna- tional Standards. The American National Standards Institute, Inc, is the United States member of ISO. The work of developing International Standards is normally carried out through IS0 tech- nical committees. Each member body interested in a subject

12、 for which a technical com- mittee has been established has the right to be represented on that committee. Interna- tional organizations, governmental and nongovernmental. in liaison with ISO, also take part in the work. Draft International Standards adopted by the technical committees are circulate

13、d to the member bodies for approval before their acceptance as International Standards by the IS0 Council. They are approved in accordance with IS0 procedures requiring at least 75% approval by the member bodies voting. Whenever possible, an IS0 standard wiIl be adopted to replace a comparable Ameri

14、can National Standard to avoid dual standard situations that could result in incompatibility. It should be mentioned that certain conventions, spelling, and units in International Stan- dards are different from those normally used in American National Standards, but this is not expected to cause dif

15、ficulty in understanding or use. International Standard for Photography - Black-and-White Aerial Camera Films - Deter- mination of IS0 Speed and Average Gradient, IS0 7829-1986, was prepared by Technical Committee ISO/TC42, Photography. The text of IS0 7829-1986 has been adopted in this revision of

16、American National Standard Method for Determining the Speeds of Mono- chrome Photographic Negative Films for Aerial Photography, ANSI PH2.34-1969. Changes in aerial photography over the last ten years, particularly those related to the increased use of mechanized processing, have made it necessary t

17、o eliminate processmg restrictions in order to provide the user with realistic IS0 speed and average gradient values. Therefore, this standard does not specify the processing conditions but does pro- vide a method for measuring the speed of various film-process combinations. Suggestions for the impr

18、ovement of this standard will be welcome. They should be sent to the National Association of Photographic Manufacturers, Inc, 600 Mamaroneck Ave- nue, Harrison. NY 10528. This standard was processed and approved for submittal to ANSI by Accredited Stan- dards Committee on Photographic Sensitometry,

19、PH2. Committee approval of the stan- dard does not necessarily imply that all committee members voted for its approval. At the time it approved this standard. the PH2 committee had the following members: Walter J. Irving. Chairman Richard J. Byer. Vice-Chairman Charles G. Saleski. Secretary Organiza

20、tion Represented Name of Representative American Roentgen Society. . . . . . . . . . . . . . . . . American Society for Nondestructive Testing. . . . . . Association for Information and Image Management. . . . Association of Reproduction Materials Manufacturers, Inc Azon Corporation. . . . . . . . .

21、 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Marvin E. Haskin Robert C. Placious Solomon Coldspiel (Alt) Marilyn Courtot Sigid Anderson (Ah) Philip P. Nowers Robert C. Johnson (Alt) Edward C. Bialczak Albert Levit (Ah) Organization Represented Name of Representative Canachan Stan

22、dards Association (Liaison) . Cosar Corporation DatagraphiX, Inc . Graphic Communications Association . GTI Graphic Technology, Inc International Busmess Machines Corporation . National Association of Photographic Manufacturers, lnc Optical Society of America . Photographic Society of America. . Pro

23、fessional Photographers of America, Inc Radiological Society of North America Sargent-Welch Scientific Company . Society of Photopaphic Scientists and Engineers. U.S. Department of the Air Force . U.S. Department of the Army. . U.S. Department of Commerce - NatIonal Bureau of Standards U.S. Departme

24、nt of Health and Human Services - Food and Drug AdministratIon. . U.S. Department of the Navy U.S. General Services Administration - Federal Supply and Services. Xidex Corporation . . . . . D. Somers . James R. Co Sherman H. Boyd Norman W. Scharpf Peter Brehm (Alt) Charles C. Saleski Joseph F. Comis

25、key Harry Atwood Rlchad J. Byer W the aim being to create an International Standard that would incorporate the most important features of these standards. Changes in aerial photography over the last 10 years, par- ticularly those related to the increased use of mechanized pro- cessing, has made it n

26、ecessary to eliminate the processing restrictions present in some of the existing standards in order to provide the user with realistic IS0 speed and average gradient values. Assigning speed values to aerial films presents problems. Aerial films are required to record or even amplify the small varia

27、tions in luminance that exist when the earth is viewed from altitudes of several kilometres or as low as 20 to 30 m where the luminance range may be of the same order as that of ordinary ground photography. In the first case, the films are developed to a high average gradient or contrast; and in the

28、 second case, to a very low average gradient. In addition to the factor of elevation (slant range). the luminance range of the subject rnat- ter may be further modified by aerial haze, solar altitude, and contrast (ratio of sunlight to skylight). Modifying the process- ing of a given aerial film, or

29、 the selection of film emulsions hav- ing certain preferred gradation characteristics, are methods commonly used for obtaining optimum information. Since there is no ideal, “gamma”, “average gradient”, or any other characteristics that can be ascribed to an aerial film for all applications, no singl

30、e contrast or degree of development as a measure of film contrast is specified in this International Stan- dard for determining film speed. Therefore, it is possible for a film to have several speed and average gradient values assigned to it depending on the processing conditions. At the preeent tim

31、e, there are a number of processing methods that can be used for aerial films. Some of them are difficult to define or may not be representative of all conditions under which aerial films will be processed. Most standards for deter- mining the speed of aerial films specify a single process for deter

32、mining speed, but the values obtained are of limited use and are seldom used due to lack of correlation with practical applications. In recognition of these factors, this International Standard does not specify the processing conditions, but provides a method for measuring the speed of various film-

33、process combinations; this means that a description of both the film and process used shall be given when quoting IS0 speed values. Therefore, a single film product may have several speed values associated with it depending not only on the extent of development in a particular process, but also on t

34、he type of developer, machine, etc., used. The density at which the speed is calculated is 0.30 above base plus fog which is considered a compromise be- tween minimizing the influence of contrast variations on speed and the minimum density to which aerial films are exposed. A method for determining

35、the IS0 aerial average gradient is also described in this International Standard. Since IS0 aerial speed is dependent on the extent of development, it is sug- gested the IS0 average gradient values be provided whenever IS0 speed is given, for example, IS0 AM/(? 1.6. It should however, be recognized

36、that other characteristics such as fog, image quality, etc. may also be affected by the extent of development. 1 Scope and field of application This International Standard specifies the method for determin- ing the IS0 aerial speed and IS0 aerial average gradient of black-and-white negative camera f

37、ilm-process combinations used in aerial photography. This International Standard does not apply to infrared aerial filmS. 2 References IS0 5, Photography - Dens measurements - Part 2 : Geometric conditions for transmission density. - Pert 3 : Spectral conditions. IS0 554, Standard etmospheres for co

38、nditioning andl or testing - Specifications. CIE Publication No. 15 (E-1.3.1.) 1971, Calorimetry. ANSI/IS0 7829-1986, ANSI PH2.34-1987 3 Definitions For the purpose of this International Standard the following definitions apply. 3.1 exposure, H : The time integral of illuminance on the film measured

39、 in lux seconds and designated by the symbol H. NOTE - Exposure is often expressed in logloH units. 3.2 speed : A quantitative measure of the response of the photographic film-process combination to radiant energy for the specified conditions of exposure, processing, and image measurement. 3.3 avera

40、ge gradient : The slope of the straight line joining two points on a sensitometric curve. 4 Sampling and storage In determining the IS0 speed of a product, it is important that the samples evaluated yield the average results obtained by users. This will require evaluating several different batches p

41、eriodically under the conditions specified in this International Standard. Prior to evaluation, the samples shall be stored ac- cording to the manufacturers recommendations for a length of time to simulate the average age at which the product is nor- mally used. Several independent evaluations shall

42、 be made to ensure the proper calibration of equipment and processes. The basic objective in selecting and storing samples as described above is to ensure the film characteristics are representative of those obtained by a photographer at the time of use. 5 Method of test 6.1 Principle Samples are ex

43、posed and processed as specified below. Den- sity measurements are obtained from the resultant image to produce a sensitometric curve from which values are taken and used to determine IS0 aerial speed and IS0 aerial average gradient values. 5.2 Safelights To eliminate the possibility of safelight il

44、lumination affecting the sensitometric results, all films shall be handled in complete darkness during exposing and processing. 5.3 Exposure 5.3.1 Sample condition During exposure, the samples shall be at a temperature of 23 f 2X and a relative humidity of 50 f 5 %. Thus is the recommended atmospher

45、e and normal tolerances specified in IS0 554 for test results. 5.3.2 Type of sensitometer The sensitometer shall be a non-Intermittent, illuminance-scale type. 5.3.3 Radiant energy quality 5.3.3.1 Relative spectral power distribution The relative spectral power distribution of the illuminant shall b

46、e as specified in table 1. These values were derived by multiplying the relative spectral power distribution values for Dg, by the transmittance values, r, of an IS0 standard aerial camera lens. 5.3.3.2 Filters IS0 speed shall be specified for use without a filter in front of the camera lens. If fil

47、m is used with a colour filter in front of the camera lens, an “equivalent” speed number can be used to Table 1 - Relative spectral power distribution of IS0 sensitometric aerial daylight Wavelength, A Relative rpectral power dirtribution of aerial photographic daylight Relative Ion8 Intarnatlonal s

48、tandard sensitometric transmittance aerial photographic daylight illuminant (nml DeO Relative* 1 power Tolerances 360 36 0 0 oto +2 400 71 26 16 16to 22 460 106 70 74 mto 63 500 103 89 92 66to1a3 560 102 99 100 0 6uo 90 99 m ato 98 660 82 99 61 74to 90 700 76 96 74 67to 82 750 66 96 63 66to 71 This

49、is the CIE Standard illuminant representing a phase of daylight with a correlated colour temperature of 6 CO3 K normalized to 102 at 560 nm. l * This relative power distribution may be approximated by the use of a 2 664 K tungsten source, an appropnate daylight conversion filter lfor example Coming filter 5900 or equivalent1 and a heat absorbing filter. 8 ANSI/IS0 7829-1986, ANSI PH2.34-1987 determine the exposure of the film with the filter. IS0 speed does not apply to the filtered condition. 5.3.4 Modulation The total range of spectral diffuse transmission density with respect t