ISO 7829:1986
(Main)Photography — Black-and-white aerial camera films — Determination of ISO speed and average gradient
Photography — Black-and-white aerial camera films — Determination of ISO speed and average gradient
Describes a method for determining the speed and average gradient of black-and-white negative films used in aerial photography. Depending on the processing conditions, a single film product may have several speed and gradient values. The specifications do not apply to infrared aerial films.
Photographie — Films noir et blanc pour photographie aérienne — Détermination de la sensibilité et du contraste moyen ISO "Aviation"
Fotografija - Črno-beli filmi za letalske kamere - Določanje splošne občutljivosti in povprečnega gradienta
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International Standard
INTERNATIONAL ORGANIZATION FOR STANDARDIZATION.ME~YHAPOJklAR OPrAHM3ALWlR fl0 CTAH~APTM3AL(MM@ORGANISATION INTERNATIONALE DE NORMALISATION
Black-and-white aerial Camera films -
Photography -
Determination of ISO Speed and average gradient
Dhtermination de Ia sensibilit6 et du contraste mo yen ISO
Photographe - Fifms noir et blanc pour photographie ahrienne -
NA via tiorw
First edition - 19864845
Ref. No. ISO 78294986 (E)
UDC 771534.5 : 778.35
roll films, tests, determination, sensitivity
Descriptors : photography, aerial photography, black-and-white photography, photographic film,
(photography).
Price based on 9 pages
---------------------- Page: 1 ----------------------
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of
national Standards bodies (ISO member bedies). The work of preparing International
Standards is normally carried out through ISO technical committees. Esch 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, govern-
mental and non-governmental, in liaison with ISO, also take patt in the work.
. Draft International Standards adopted by the technical committees are circulated to
the member bodies for approval before their acceptance as International Standards by
the ISO Council. They are approved in accordance with ISO procedures requiring at
least 75 % approval by the member bodies voting.
International Standard ISO 7829 was prepared by Technical Committee ISO/TC 42,
Photograph y.
Users should note that all International Standards undergo revision from time to time
and that any reference made herein to any other International Standard implies its
latest edition, unless otherwise stated.
0 International Organkation for Standardization, 1966
Printed in Switzerland
---------------------- Page: 2 ----------------------
ISO 78294986 (E)
INTERNATIONAL STANDARD
Photography - Black-and-white aerial Camera films -
Determination of ISO Speed and average gradient
0 lntroduction In recognition of these factors, this International Standard does
not specify the processing conditions, but provides a method
ISO was requested to develop a method for measuring Speed for measuring the Speed of various film-process combinations;
and average gradient of black-and-white negative Camera film- this means that a description of both the film and process used
shall be given when quoting ISO Speed values. Therefore, a
process combinations used in aerial photography because of
the incompatability of various existing Standards; the aim being Single film product may have several Speed values associated
with it depending not only on the extent of development in a
to create an International Standard that would incorporate the
most important features of these Standards. particular process, but also on the type of developer, machine,
etc., used. The density at which the Speed is calculated is 0,30
Changes in aerial photography over the last 10 years, par- ab*ove base plus fog which is considered a compromise be-
ticularly those related to the increased use of mechanized pro- tween minimizing the influence of contrast variations on Speed
cessing, has made it necessary to eliminate the processing and the minimum density to which aerial films are exposed.
restrictions present in some of the existing Standards in Order to
provide the user with realistic ISO Speed and average gradient
values.
A method for determining the ISO aerial average gradient is
also described in this International Standard. Since ISO aerial
Assigning Speed values to aerial films presents Problems. Aerial
Speed is dependent on the extent of development, it is sug-
films are required to record or even amplify the small variations
gested the ISO average gradient values be provided whenever
in luminance that exist when the earth is viewed from altitudes
ISO Speed is given, for example, ISO A64O/G 1.6. lt should
of several kilometres or as low as 20 to 30 m where the
however, be recognized that other characteristics such as fog,
luminance range may be of the same Order as that of ordinary
image quality, etc. may also be affected by the extent of
ground photography. In the first case, the films are developed .
development.
to a high average gradient or contrast; and in the second case,
to a very low average gradient. In addition to the factor of
elevation (slant range), the luminance range of the subject mat-
1 Scope and field of application
ter may be further modified by aerial haze, solar altitude, and
contrast (ratio of sunlight to Skylight). Modifying the process-
This International Standard specifies the method for determin-
ing of a given aerial film, or the selection of film emulsions hav-
ing the ISO aerial Speed and ISO aerial average gradient of
ing certain preferred gradation characteristics, are methods
black-and-white negative Camera film-process combinations
commonly used for obtaining Optimum information.
used in aerial photography.
Since there is no ideal, “gamma”, “average gradient”, or any
This International Standard does not apply to infrared aerial
other characteristics that tan be ascribed to an aerial film for all films.
applications, no Single 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
2 References
to it depending on the processing conditions.
ISO 5, Photography - Den& measurements
At the present time, there are a number of processing methods
- Part 2 : Geometrie conditions for transmission density.
that tan be used for aerial films. Some of them are difficult to
- Part 3 : Spectral conditions.
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 ISO 554, Standard atmospheres for conditioning and/or testing
determining Speed, but the values obtained are of limited use - Specifica tions.
and are seldom used due to lack of correlation with practical
applications. CIE Publication No. 15 (E-1.3.1.) 1971, Colorimetry.
1
---------------------- Page: 3 ----------------------
ISO 7829-1986 (E)
produce a sensitometric curve from which values are taken and
3 Def initions
used to determine ISO aerial Speed and ISO aerial average
For the purpose of this International Standard the following gradient values.
definitions apply.
5.2 Safelights
3.1 exposure, H : The time integral of illuminance on the
film measured in lux seconds and designated by the Symbol H.
To eliminate the possibility of safelight il lumination affecting
the sensitometric results, all films shall be handled in complete
NOTE - Exposure is often expressed in logl0H units.
darkness during exposing and processing
3.2 Speed : A quantitative measure of the response of the
5.3 Exposure
photographic film-process combination to radiant energy for
the specified conditions of exposure, processing, and image
measurement.
5.3.1 Sample condition
During exposure, the samples shall be at a temperature of
3.3 average gradient : The slope of the straight line joining
23 + 2OC and a relative humidity of 50 + 5 %. This is the
two Points on a sensitometric curve.
recommended atmosphere and normal tolerantes specified in
ISO 554 for test results.
4 Sampling and storage
5.32 Type of sensitometer
In determining the ISO Speed of a product, it is important that
the samples evaluated yield the average results obtained by
The sensitometer shall be a non-intermittent, illuminance-scale
users. This will require evaluating several different batches
WPe*
periodically under the conditions specified in this International
Standard. Prior to evaluation, the samples shall be stored ac-
5.3.3 Radiant energy quality
cording to the manufacturers’ recommendations for a length of
time to simulate the average age at which the product is nor-
5.3.3.1 Relative spectral power distribution
mally used. Several independent evaluations shall be made to
ensure the proper calibration of equipment and processes. The
The relative spectral power distribution of the illuminant shall
basic objective in selecting and storing samples as described
above is to ensure the film characteristics are representative of be as specified in table 1. These values were derived by
those obtained by a photographer at the time of use. multiplying the relative spectral power distribution values for
Da by the transmittance values, z, of an ISO Standard aerial
Camera lens.
5 Method of test
5.3.3.2 Filters
5.1 Principle
ISO Speed shall be specified for use without a filter in front of
Samples are exposed and processed as specified below. Den- the Camera lens. If film is used with a colour filter in front of the
Camera lens, an “equivalent” Speed number tan be used to
sity measurements are obtained from the resultant image to
Table 1 - Relative spectral power distribution of ISO sensitometric aerial daylight
Relative spectral
,International Standard sensitometric
power distribution Relative lens
Wavelength, A
of aerial photographic transmittance aerial photographic daylight illuminant
daylight
Relative**
t Tolerantes
(nm)
40+
power
350 35 0 0 Oto +2
400 71 26 18 16to 22
450 106 70 74 69to 83
500 103 89 92 85 to 103
550 102 98 100 0
600 90 99 89 83 to 98
650 82 99 81 74 to 90
700 75 98 74 67 to 82
750 66 96 63 58to 71
* This is the CIE Standard illuminant representing a Phase of daylight with a correlated colour temperature of 6 003 K normalized to 102 at 550 nm.
** This relative power distribution may be approximated by the use of a 2 854 K tungsten Source, an appropriate daylight conversion filter (for
example Corning filter 5900 or equivalent) and a heat absorbing filter.
2
---------------------- Page: 4 ----------------------
ISO 7829-1986 (El
determine the exposure of the film with the filter. ISO Speed should be aware that other sensitometric and physical Hanges
does not apply to the filtered condition. may also accompany the Speed and average gradient changes.
5.3.4 Modulation
5.5 Densitometry
The total range of spectral diffuse transmission density with
ISO Standard visual diffuse transmission densities are obtained
respect to the film plane of each area of the light modulator
from the image using a densitometer complying with the
throughout the wavelength interval from &O to 750 nm, shall
geometric requirements specified in ISO 5/2 and the spectral
not exceed 5 % of the average density obtained over the same
requirements specified in ISO 5/3. A minimum aperture area of
interval or 0,03 density, whichever is greater. In the interval
7 mm2 shall be used to minimize the effect of image non-
from 360 to 400 nm, 10 % of this same average density, or 0,06
uniformity. Readings shall be at least 1 mm from the edges of
density, whichever is greater, is acceptable.
the exposures.
If stepped increments are used, the exposure increment shall
5.6 Evaluation
not be greater than 0,20 logloH units per Step. The width and
length of a Single step shall be adequate to obtain a uniform
density, devoid of edge effects, within the minimum reading
5.6.1 Sensitometric curve
aperture specified for densitometry.
ISO Standard visual diffuse transmission density values are
If continuous variable modulation is used, the Change in ex-
plotted against the logarithm to the base 10 of the correspon-
posure with distance along the test Strip shall be uniform and
ding exposures (H) expressed in lux seconds to obtain a sen-
not be greater than 0,04, loglOH units per millimetre.
sitometric cutve similar to that illustrated in figure 1.
5.3.5 Exposure time
5.6.2 Base plus fog density
The exposure time shall correspond with the usage practice for
The base plus fog density shall be determined from an unex-
the particular film tested. Since the Speed of film is dependent
posed area of the film.
on the exposure time because of reciprocity law failure effects,
the exposure time used for determining ISO Speed and average
gradient shall be specified in the use instructions.
6 Product classification
An area of the film shall not be exposed, to produce the
minimum density possible.
6.1 ISO aerial Speed
The ISO aerial Speed scale given in table 2 is derived from the
formula
5.4 Processing
1,5
5.4.1 Conditioning of samples
=-
s
Hrn
In the time interval between exposure and processing, the
samples shall be kept at 23 + 2 OC and a relative humidity of where
50 + 5 %. The processing shall be started between 1 h and
S is the ISO aerial Speed;
2 h after exposure.
H,,, is the exposure, in lux seconds, required to produce a
5.4.2 Processing specifications
density of 030 above base plus fog density.
No processing specifications are described in this International
“ISO” aerial Speed shall be obtained directly from log10 Hm by
Standard, in recognition of the wide range of chemicals and
use of
...
SLOVENSKI STANDARD
SIST ISO 7829:1997
01-september-1997
)RWRJUDILMDýUQREHOLILOPL]DOHWDOVNHNDPHUH'RORþDQMHVSORãQHREþXWOMLYRVWLLQ
SRYSUHþQHJDJUDGLHQWD
Photography - Black-and-white aerial camera films - Determination of ISO speed and
average gradient
Photographie - Films noir et blanc pour photographie aérienne - Détermination de la
sensibilité et du contraste moyen ISO "Aviation"
Ta slovenski standard je istoveten z: ISO 7829:1986
ICS:
37.040.20 )RWRJUDIVNLSDSLUILOPLLQ Photographic paper, films
IRWRJUDIVNHSORãþH)LOPVNL and cartridges
]YLWNL
SIST ISO 7829:1997 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
---------------------- Page: 1 ----------------------
SIST ISO 7829:1997
---------------------- Page: 2 ----------------------
SIST ISO 7829:1997
International Standard
INTERNATIONAL ORGANIZATION FOR STANDARDIZATION.ME~YHAPOJklAR OPrAHM3ALWlR fl0 CTAH~APTM3AL(MM@ORGANISATION INTERNATIONALE DE NORMALISATION
Black-and-white aerial Camera films -
Photography -
Determination of ISO Speed and average gradient
Dhtermination de Ia sensibilit6 et du contraste mo yen ISO
Photographe - Fifms noir et blanc pour photographie ahrienne -
NA via tiorw
First edition - 19864845
Ref. No. ISO 78294986 (E)
UDC 771534.5 : 778.35
roll films, tests, determination, sensitivity
Descriptors : photography, aerial photography, black-and-white photography, photographic film,
(photography).
Price based on 9 pages
---------------------- Page: 3 ----------------------
SIST ISO 7829:1997
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of
national Standards bodies (ISO member bedies). The work of preparing International
Standards is normally carried out through ISO technical committees. Esch 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, govern-
mental and non-governmental, in liaison with ISO, also take patt in the work.
. Draft International Standards adopted by the technical committees are circulated to
the member bodies for approval before their acceptance as International Standards by
the ISO Council. They are approved in accordance with ISO procedures requiring at
least 75 % approval by the member bodies voting.
International Standard ISO 7829 was prepared by Technical Committee ISO/TC 42,
Photograph y.
Users should note that all International Standards undergo revision from time to time
and that any reference made herein to any other International Standard implies its
latest edition, unless otherwise stated.
0 International Organkation for Standardization, 1966
Printed in Switzerland
---------------------- Page: 4 ----------------------
SIST ISO 7829:1997
ISO 78294986 (E)
INTERNATIONAL STANDARD
Photography - Black-and-white aerial Camera films -
Determination of ISO Speed and average gradient
0 lntroduction In recognition of these factors, this International Standard does
not specify the processing conditions, but provides a method
ISO was requested to develop a method for measuring Speed for measuring the Speed of various film-process combinations;
and average gradient of black-and-white negative Camera film- this means that a description of both the film and process used
shall be given when quoting ISO Speed values. Therefore, a
process combinations used in aerial photography because of
the incompatability of various existing Standards; the aim being Single film product may have several Speed values associated
with it depending not only on the extent of development in a
to create an International Standard that would incorporate the
most important features of these Standards. particular process, but also on the type of developer, machine,
etc., used. The density at which the Speed is calculated is 0,30
Changes in aerial photography over the last 10 years, par- ab*ove base plus fog which is considered a compromise be-
ticularly those related to the increased use of mechanized pro- tween minimizing the influence of contrast variations on Speed
cessing, has made it necessary to eliminate the processing and the minimum density to which aerial films are exposed.
restrictions present in some of the existing Standards in Order to
provide the user with realistic ISO Speed and average gradient
values.
A method for determining the ISO aerial average gradient is
also described in this International Standard. Since ISO aerial
Assigning Speed values to aerial films presents Problems. Aerial
Speed is dependent on the extent of development, it is sug-
films are required to record or even amplify the small variations
gested the ISO average gradient values be provided whenever
in luminance that exist when the earth is viewed from altitudes
ISO Speed is given, for example, ISO A64O/G 1.6. lt should
of several kilometres or as low as 20 to 30 m where the
however, be recognized that other characteristics such as fog,
luminance range may be of the same Order as that of ordinary
image quality, etc. may also be affected by the extent of
ground photography. In the first case, the films are developed .
development.
to a high average gradient or contrast; and in the second case,
to a very low average gradient. In addition to the factor of
elevation (slant range), the luminance range of the subject mat-
1 Scope and field of application
ter may be further modified by aerial haze, solar altitude, and
contrast (ratio of sunlight to Skylight). Modifying the process-
This International Standard specifies the method for determin-
ing of a given aerial film, or the selection of film emulsions hav-
ing the ISO aerial Speed and ISO aerial average gradient of
ing certain preferred gradation characteristics, are methods
black-and-white negative Camera film-process combinations
commonly used for obtaining Optimum information.
used in aerial photography.
Since there is no ideal, “gamma”, “average gradient”, or any
This International Standard does not apply to infrared aerial
other characteristics that tan be ascribed to an aerial film for all films.
applications, no Single 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
2 References
to it depending on the processing conditions.
ISO 5, Photography - Den& measurements
At the present time, there are a number of processing methods
- Part 2 : Geometrie conditions for transmission density.
that tan be used for aerial films. Some of them are difficult to
- Part 3 : Spectral conditions.
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 ISO 554, Standard atmospheres for conditioning and/or testing
determining Speed, but the values obtained are of limited use - Specifica tions.
and are seldom used due to lack of correlation with practical
applications. CIE Publication No. 15 (E-1.3.1.) 1971, Colorimetry.
1
---------------------- Page: 5 ----------------------
SIST ISO 7829:1997
ISO 7829-1986 (E)
produce a sensitometric curve from which values are taken and
3 Def initions
used to determine ISO aerial Speed and ISO aerial average
For the purpose of this International Standard the following gradient values.
definitions apply.
5.2 Safelights
3.1 exposure, H : The time integral of illuminance on the
film measured in lux seconds and designated by the Symbol H.
To eliminate the possibility of safelight il lumination affecting
the sensitometric results, all films shall be handled in complete
NOTE - Exposure is often expressed in logl0H units.
darkness during exposing and processing
3.2 Speed : A quantitative measure of the response of the
5.3 Exposure
photographic film-process combination to radiant energy for
the specified conditions of exposure, processing, and image
measurement.
5.3.1 Sample condition
During exposure, the samples shall be at a temperature of
3.3 average gradient : The slope of the straight line joining
23 + 2OC and a relative humidity of 50 + 5 %. This is the
two Points on a sensitometric curve.
recommended atmosphere and normal tolerantes specified in
ISO 554 for test results.
4 Sampling and storage
5.32 Type of sensitometer
In determining the ISO Speed of a product, it is important that
the samples evaluated yield the average results obtained by
The sensitometer shall be a non-intermittent, illuminance-scale
users. This will require evaluating several different batches
WPe*
periodically under the conditions specified in this International
Standard. Prior to evaluation, the samples shall be stored ac-
5.3.3 Radiant energy quality
cording to the manufacturers’ recommendations for a length of
time to simulate the average age at which the product is nor-
5.3.3.1 Relative spectral power distribution
mally used. Several independent evaluations shall be made to
ensure the proper calibration of equipment and processes. The
The relative spectral power distribution of the illuminant shall
basic objective in selecting and storing samples as described
above is to ensure the film characteristics are representative of be as specified in table 1. These values were derived by
those obtained by a photographer at the time of use. multiplying the relative spectral power distribution values for
Da by the transmittance values, z, of an ISO Standard aerial
Camera lens.
5 Method of test
5.3.3.2 Filters
5.1 Principle
ISO Speed shall be specified for use without a filter in front of
Samples are exposed and processed as specified below. Den- the Camera lens. If film is used with a colour filter in front of the
Camera lens, an “equivalent” Speed number tan be used to
sity measurements are obtained from the resultant image to
Table 1 - Relative spectral power distribution of ISO sensitometric aerial daylight
Relative spectral
,International Standard sensitometric
power distribution Relative lens
Wavelength, A
of aerial photographic transmittance aerial photographic daylight illuminant
daylight
Relative**
t Tolerantes
(nm)
40+
power
350 35 0 0 Oto +2
400 71 26 18 16to 22
450 106 70 74 69to 83
500 103 89 92 85 to 103
550 102 98 100 0
600 90 99 89 83 to 98
650 82 99 81 74 to 90
700 75 98 74 67 to 82
750 66 96 63 58to 71
* This is the CIE Standard illuminant representing a Phase of daylight with a correlated colour temperature of 6 003 K normalized to 102 at 550 nm.
** This relative power distribution may be approximated by the use of a 2 854 K tungsten Source, an appropriate daylight conversion filter (for
example Corning filter 5900 or equivalent) and a heat absorbing filter.
2
---------------------- Page: 6 ----------------------
SIST ISO 7829:1997
ISO 7829-1986 (El
determine the exposure of the film with the filter. ISO Speed should be aware that other sensitometric and physical Hanges
does not apply to the filtered condition. may also accompany the Speed and average gradient changes.
5.3.4 Modulation
5.5 Densitometry
The total range of spectral diffuse transmission density with
ISO Standard visual diffuse transmission densities are obtained
respect to the film plane of each area of the light modulator
from the image using a densitometer complying with the
throughout the wavelength interval from &O to 750 nm, shall
geometric requirements specified in ISO 5/2 and the spectral
not exceed 5 % of the average density obtained over the same
requirements specified in ISO 5/3. A minimum aperture area of
interval or 0,03 density, whichever is greater. In the interval
7 mm2 shall be used to minimize the effect of image non-
from 360 to 400 nm, 10 % of this same average density, or 0,06
uniformity. Readings shall be at least 1 mm from the edges of
density, whichever is greater, is acceptable.
the exposures.
If stepped increments are used, the exposure increment shall
5.6 Evaluation
not be greater than 0,20 logloH units per Step. The width and
length of a Single step shall be adequate to obtain a uniform
density, devoid of edge effects, within the minimum reading
5.6.1 Sensitometric curve
aperture specified for densitometry.
ISO Standard visual diffuse transmission density values are
If continuous variable modulation is used, the Change in ex-
plotted against the logarithm to the base 10 of the correspon-
posure with distance along the test Strip shall be uniform and
ding exposures (H) expressed in lux seconds to obtain a sen-
not be greater than 0,04, loglOH units per millimetre.
sitometric cutve similar to that illustrated in figure 1.
5.3.5 Exposure time
5.6.2 Base plus fog density
The exposure time shall correspond with the usage practice for
The base plus fog density shall be determined from an unex-
the particular film tested. Since the Speed of film is dependent
posed area of the film.
on the exposure time because of reciprocity law failure effects,
the exposure time used for determining ISO Speed and average
gradient shall be specified in the use instructions.
6 Product classification
An area of the film shall not be exposed, to produce the
minimum density possible.
6.1 ISO aerial Speed
The ISO aerial Speed scale given in table 2 is derived from the
formula
5.4 Processing
1,5
5.4.1 Conditioning of samples
=-
s
Hrn
In the time interval between exposure and processing, the
samples shall be kept at 23 + 2 OC and a relative humidity
...
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