1、Black-and-white pictorial still camera negative filmlprocess systems Determination of IS0 speed (IS0 6 : 1993) ICs 37.040.20 Photographie - Systeme von Schwarzwei-Negativfilmen und ihrer Verarbeitung fr Stehbildaufnahmen - Bestimmung der ISO- Empfindlichkeit (IS0 6 : 1993) Supersedes DIN 451 2-1, Ma
2、y 1993 edition. DIN IS0 6 - This standard incorporates International Standard IS0 6 Photography- Black-and-white pictorial still camera negative film/process systems - Determination of IS0 speed. A comma is used as the decimal marker, National foreword This standard has been prepared by ISO/TC 42. T
3、he responsible German body involved in its preparation was the Normenausschuss Bild undFilm (Cinema- tography and Photography Standards Committee), Technical Committee Sensitometrie. The DIN Standards corresponding to the International Standards referred to in clause 2 of the IS0 Standard are as fol
4、lows: IS0 5-2 DIN 451 2-8 IS0 5-3 DIN 451 2-9 IS0 7589 DIN 451 2-6 Amendments DIN 451 2-1, May 1993 edition, has been superseded by the specifications of DIN IS0 6. Previous editions DIN 451 2: 1934-01 ; DIN 451 2-1 : 1957-1 1, 1961 -1 O, 1971 -04, 1993-05. National Annex NA Standards referred to (a
5、nd not included in Normative references and Annex B) DIN 451 2-6 Sensitometric illuminants and light sources DIN 451 2-8 Photographic sensitometry - Determination of optical density - Geometric conditions for transmission density DIN 451 2-9 Determination of optical density - Spectral conditions IS0
6、 Standard comprises 7 pages. Q No part of this standard may be reproduced without the prior permission of DIN Deutsches Institut fr Normung e. V., Berlin. Beuth Verlag GmbH, 10772 Berlin, Germany, has the exclusive right of sale for German Standards (DIN-Normen). Ref. No. DIN IS0 6 : 1996-02 English
7、 price group 07 Sales No. 0407 08.00 Page 1 IS0 6 : 1993 Photography Black-and-white pictorial still camera negative fi Im/process systems Determination of IS0 speed Foreword IS0 (the International Organization for Standardization) is a worldwide federation of national standards bodies (IS0 member b
8、odies). The work of preparing International Standards is normally carried out through IS0 technical committees. Each member body interested in a subject for which a technical committee has been established has the right to be represented on that committee. International organizations, governmental a
9、nd non-governmental, in liaison with ISO, also take part in the work. IS0 collaborates closely with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization. Draft International Standards adopted by the technical committees are circulated to the member b
10、odies for voting. Publication as an International Standard requires approval by at least 75 % of the member bodies casting a vote. International Standard IS0 6 was prepared by Technical Committee ISO/TC 42, Photography. This second edition cancels and replaces the first edition (IS0 6:1974). The pri
11、mary change is to eliminate the restriction that the IS0 speed of all black-and-white films be determined in a specified developer and fixing bath. It also updates references, procedures and the format in accordance with more recent speed standards for other film types. Annexes A and B of this Inter
12、national Standard are for information only. Page 2 IS06: 1993 Introduction Black-and-white films will generally provide excellent results in several different developers and processing conditions. At the same time, it is realized that the speed of a film depends on the process used. Therefore, this
13、International Standard specifies a method for determining the photo- graphic speed of film/process combinations. This means a particular film may have several IS0 speeds associated with it depending on the pro- cesses used. For this reason, it is important that manufacturers indicate the processing
14、conditions for which IS0 speed values are quoted. This International Standard recognizes that black-and-white films do not generally have a unique speed if several different processes are rec- ommended. This conflicts with the tradition of associating a specific speed value with a particular product
15、. In the future, the process used for deter- mining speed values should be unequivocally described to avoid misinter- pretation. Since users often do not know how these films will be processed, manufacturers have an obligation to provide a speed value for this situation which will ensure good result
16、s. Usually they will take ad- vantage of the overexposure tonal latitude of the film and give it a con- servative speed value to protect users from underexposure effects in case the film is put through a process which yields low speed. It is recognized that the speed at which a film can be exposed i
17、s de- pendent on the extent of development, scene luminance range, subject matter, printing paper, etc. This International Standard specifies that film/process speed is determined when the film is processed to obtain a specified contrast level. The relative IS0 speed ranking of various films in diff
18、erent process systems will generally differ. The IS0 speeds will pro- vide correct exposures for average scenes with exposure meters con- forming to IS0 2720 or IS0 2721 when the film is processed as specified in this International Standard. 1 Scope Page 3 IS0 6 : 1993 3 Definitions This Internation
19、al Standard specifies the method for determining the IS0 speed of black-and-white nega- tive camera films used for pictorial still photography. This International Standard applies to films processed in conventional chemicals and equipment, but also to those processed using special procedures such as
20、 those involving activators or heat for development. This International Standard does not apply to motion- picture, aerial photography, graphic arts, radiographic or micrographic applications, nor to negatives prod- uced in diffusion transfer systems. 2 Normative references The following standards c
21、ontain provisions which, through reference in this text, constitute provisions of this International Standard. At the time of publi- cation, the editions indicated were valid. All standards are subject to revision, and parties to agreements based on this International Standard are encouraged to inve
22、stigate the possibility of applying the most re cent editions of the standards indicated below. Members of IEC and IS0 maintain registers of cur- rently valid International Standards. IS0 5-21 991, Photography - Density measurements - Part 2: Geometric conditions for transmission density. IS0 5-3:19
23、84, Photography - Density measurements - Part 3: Spectral conditions. IS0 7589:1984, Photography - Illurninants for sensitometry - Specifications for daylight and incan- descent tungsten. For the purposes of this International Standard, the following definitions apply. 3.1 exposurer H: The time inte
24、gral of illuminance on the film, measured in lux seconds. Amounts of exposure are often expressed in logarith- mic terms (log,. 3.2 speed: A quantitative measure of the response of the photographic material to radiant energy for the specified conditions of exposure, processing and im- age measuremen
25、t. 4 Sampling and storage In determining the IS0 speed of a product, it is im- portant that the evaluated samples yield the average results obtained by users. This will require evaluating several different batches periodically under the con- ditions specified in this International Standard. Prior to
26、 evaluation, the samples shall be stored according to the manufacturers recommendations for a length of time to simulate the average age at which the product is normally used. Several independent evaluations shall be made to ensure the proper calibration of equipment and processes. The basic objecti
27、ve in se- lecting 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 Test method 5.1 Principle Samples are exposed and processed as specified be- low. Density measurements are obtained from the res
28、ultant images to produce a sensitometric curve from which values are taken and used to determine IS0 speed. Page 4 IS06: 1993 5.2 Safelights To eliminate the possibility of unintentional exposure to radiation affecting the sensitometric results, all films shall be handled in complete darkness during
29、 sample preparation and processing. 5.3.6 Exposure time 5.3 Exposure 5.3.1 Conditioning of specimens During exposure, the specimens shall be kept at a temperature of 23 “C f 2 “C and a relative humidity of (50 f 5) %. 5.3.2 Type of sensitometer The sensitometer shall be a non-intermittent, illuminan
30、ce-scale type. 5.3.3 Radiant energy quality The appropriate illuminant for the particular film type being exposed shall conform to the specifications given in IS0 7589. IS0 speed may be determined using IS0 sensitometric daylight, studio tungsten or photoflood illuminants. Since the speed of film/pr
31、ocess combinations will depend on the type of illuminant used for determining IS0 speed, the illuminant should be specified in use instructions. 5.3.4 Filters IS0 speed shall be specified for use without a filter in front of the camera lens. If film is used with a colour filter in front of the camer
32、a lens, an “equivalent“ speed number can be used to determine the ex- posure of the film with the filter. IS0 speed does not apply to the filtered conditions. 5.3.5 Modulation The total range of spectral diffuse transmission den- sity of each area of the light modulator throughout the wavelength int
33、erval from 400 nm to 700 nm shall not exceed 5 % of the average density obtained over the same interval or a value of 0,03, whichever is greater. In the interval from 360 nm to 400 nm, 10 % of this same average density, or a value of 0,06, whichever IS greater, shall not be exceeded. If stepped incr
34、ements are used, the base 10 logarithm of the exposure increment shall not be greater than 0,20. The width and length of a single step shall be adequate to obtain a uniform density within the read- ing aperture specified for densitometry. If a continuous variable modulator is used, the base 10 logar
35、ithm of the change in exposure with distance along the test strip shall be uniform and not be greater than 0,04 per millimetre. The exposure time shall be between 5 s and 1/1 O00 s corresponding to the usage practice for the particular film tested. Since the speed of film is de- pendent on exposure
36、time because of reciprocity law failure, the exposure time used for determining IS0 speed should be specified in use instructions. 5.4 Processing 5.4.1 Conditioning of specimens In the time interval between exposure and pro- cessing, the specimens shall be kept at 23 “C f 2 OC and at a relative humi
37、dity of (50 f 5) %. The pro- cessing shall be completed in not less than 5days and not more than 10 days after exposure for general-purpose films, and not less than 4 hours and not more than 7 days after exposure for professional films. 5.4.2 Processing specifications The only processing specificati
38、on required in this International Standard is that the density difference between points m and n shall be 0.80 (see 5.6.3 and figure 1). No additional processing specifications are included in recognition of the wide range of chemicals and equipment used in processing black-and-white films. IS0 spee
39、ds provided by film manufacturers generally apply to films when they are processed in accordance with their recommendations to produce the photographic characteristics specified for the process. Process information shall be available from film manufacturers or others who quote IS0 speed. This shall
40、specify the chemicals, time, temperatures, agi- tation equipment and procedure used for each of the processing steps and any additional information re- quired to obtain the sensitometric results described. The values for speed obtained using various pro- cessing procedures can differ significantly.
41、Although different speeds for a particular film can be achieved by varying the process, other sensitometric and physical changes can also accompany the speed changes. Generally, processes which yield higher IS0 speed will also increase the graininess of the negative and the final print. Page 5 IS0 6
42、 : 1993 Figure 1 - Method for determining speed 5.5 Densitometry IS0 standard Type 2 diffuse transmission density of the processed images shall be measured using a densitometer complying with the geometric con- ditions specified in IS0 5-2 and spectral conditions specified in IS0 5-3. Readings shall
43、 be made in a uni- form area of the image. 5.6 Evaluation 5.6.1 Sensitometric curve The IS0 standard Type 2 diffuse transmission density values are plotted against the base 10 logarithm of the corresponding exposure, H, expressed in lux seconds, to obtain a sensitometric curve similar to that illus-
44、 trated in figure 1. 5.6.2 Base-plus-fog density The combination of base and fog density shall be de- termined from an unexposed sample of the same film processed simultaneously with the film exposed for determining the sensitometric curve. 5.6.3 Determination of H, The method for determining speed
45、is illustrated in figure 1. Point m is located on the curve at a density of 0,l O above base plus fog density. Point n is located on the curve where the base 10 logarithm of the ex- i c u) C aI u c u) .- .- f + posure is 1,30 units greater than that at point m. The development time of the negative m
46、aterial is so cho- sen that the density difference, AD, between points m and n is 0,80 (see annex A). Then, H, represents the exposure, in lux seconds, corresponding to point m when the above condition is satisfied. 6 Product classification 6.1 IS0 speed scale The arithmetic speeds, S, and the logar
47、ithmic speeds, So, given in table1 are derived from the following equations 0,80 S=- Hrn 0,80 so = 1 + 10 log,oH, IS0 speed shall be obtained directly from log, H, by use of table1 which shows the rounded values of S and So to be used. 6.2 IS0 speed of a product The IS0 speed of a product (as distin
48、guished from that of a specific sample) shall be based on the arith- metic mean of the values of log, H, determined from various batches of the product when selected, stored and tested as specified above. The IS0 speed Page 6 IS06: 1993 of a product with proper rounding is then determined from the m
49、ean value of loglo H, using table 1. Table 1 - IS0 speed scales from - 3.65 - 3,55 - 3,45 - 3,35 - 3,25 -3.15 - 3,05 - 2.95 - 2.85 - 2.75 - 2.65 - 2.55 - 2.45 - 2.35 - 2.25 - 2.15 - 2,05 - 1.95 - 1,85 - 1,75 - 1.65 - 1,55 - 1,45 - 1,35 - 1,25 to - 3,56 - 3,46 - 3,36 - 3,26 -3.16 - 3,06 - 2,96 - 2.86 - 2,76 - 2.66 - 2.56 - 2,46 - 2,36 - 2,26 - 2.16 - 2,06 - 1,96 - 1.86 - 1,76 - 1,66 -1.56 - 1,46 - 1,36 - 1,26 -1.16 IS0 speed S 3 200 2 500 2 O00 1 600 1 250 1 O00 800 640 500 400 320 250 200 160 125 1 O0 80 64 50 40 32 25 20 16 12 SO 36“ 35“ 34“ 33“ 32“ 31 O 30“ 29“ 28“ 27“ 26“ 25“ 24“
