SIST ISO 10157:2011
Photography - Flash exposure meter - Requirements
Photography - Flash exposure meter - Requirements
This International Standard applies to photoelectric flash exposure meters which measure the time integral of the luminance or of the illuminance of a photographic object (to be called thereafter
“object”) illuminated by a source of light for a brief illumination period l) and indicate the time integral or a number corresponding to the time integral or thefinumber required for the correct exposure of a photographic film with a given speed. Continuous light, which is available in addition to the light emitted by the flash light source, is also evaluated.
NOTE 1 If the object is illuminated by electronic flash equipment with automatic exposure control, the measuring results of the flash exposure meter can deviate from the calibration values of the flash equipment.
Photographie - Exposimètre pour flash - Prescriptions
Fotografija - Svetlomer za bliskavice - Zahteve
Ta mednarodni standard velja za fotoelektrične svetlomere za bliskavice, ki merijo časovni integral svetilnosti ali intenzivnosti osvetlitve fotografskega objekta (v nadaljevanju »objekt«) in prikažejo časovni integral ali število, ki ustreza časovnemu integralu ali število, ki je potrebno za pravilno ekspozicijo fotografskega filma z dano občutljivostjo. Ovrednoti se tudi stalna svetloba, ki je na voljo poleg svetlobe, ki jo oddaja vir bliskavice.
OPOMBA 1: Če je objekt osvetljen z opremo za elektronsko bliskavico z avtomatskim nadzorom osvetlitve, rezultati merjenja svetlomera za bliskavice lahko odstopajo od kalibracijskih vrednosti opreme za bliskavice.
General Information
Standards Content (Sample)
INTERNATIONAL
STANDARD 10157
First edition
1991-06-15
Corrected and reprinted
1991-09-15
Photography - Flash exposure meter -
Requirements
Photographic - Exposimetre pour flash - Prescriptions
Reference number
IS0 10157:1991(E)
---------------------- Page: 1 ----------------------
IS0 10157:1991(E)
Foreword
IS0 (the International Organization for Standardization) is a worldwide
federation of national standards bodies (IS0 member bodies). 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, govern-
mental and 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 bodies for voting. Publication as an lnter-
national Standard requires approval by at least 75 % of the member
bodies casting a vote.
International Standard IS0 10157 was prepared by Technical Committee
ISO/TC 42, Photography.
Annex A of this International Standard is for information only.
83 IS0 1991
All rights reserved. No part of this publication may be reproduced or utilized in any form
or by any means, electronic or mechanical, including photocopying and microfilm, without
permission in writing from the publisher.
International Organization for Standardization
Case Postale 56 l CH-1211 Geneve 20 l Switzerland
Printed in Switzerland
ii
---------------------- Page: 2 ----------------------
IS0 10157:1991(E)
INTERNATIONAL STANDARD
- Flash exposure meter - Requirements
Photography
IEC 348: 1971, Safety requirements for electronic
I Scope
measuring apparatus.
This International Standard applies to photoelectric
flash exposure meters which measure the time in- 3 Definitions
tegral of the luminance or of the illuminance of a
photographic object (to be called thereafter For the purposes of this International Standard, the
“object”) illuminated by a source of light for a brief following definitions apply.
l) and indicate the time integral
illumination period
or a number corresponding to the time integral or 3.1 luminance coefficient, 4: The luminance coef-
thefinumber required for the correct exposure of a ficient, 4, is the ratio of the luminance, I,, of the
photographic film with a given speed. sample for a given observation direction to the
illuminance, E, on the sample (q = L/E).
Continuous light, which is available in addition to the
light emitted by the flash light source, is also evalu-
3.2 gate time: The gate time of the measuring cir-
ated.
cuit is the time in which the flash light meter is
measuring.
NOTE 1 If the object is illuminated by electronic flash
equipment with automatic exposure control, the measur-
3.3 storage time: The storage time is that time after
ing results of the flash exposure meter can deviate from
the end of the gate time in which the indicated value
the calibration values of the flash equipment.
changes by Ifi 7 % [corresponding to + l/IO I$*)].
3.4 acceptance angle: See definition in IS0 2720.
2 Normative references
4 Scales
The following standards contain provisions which,
Relative aperture scale, exposure time scale and
through reference in this text, constitute provisions
film speed scale are to be selected in accordance
of this International Standard. At the time of publi-
with IS0 2720.
cation, the editions indicated were valid. All stan-
dards are subject to revision, and parties to
5 General characteristic quantities of the
agreements based on this International Standard
flash exposure meter
are encouraged to investigate the possibility of ap-
plying the most recent editions of the standards in-
dicated below. Members of IEC and IS0 maintain
5.1 Measuring range
registers of currently valid International Standards.
It is recommended that the measuring range be in-
IS0 2720:1974, Photography - General purpose
dicated in candela seconds per square metre when
photographic exposure meters (photoelectric type}
measuring the time integral of luminance of the ob-
- Guide to product specification.
ject and in lux seconds when measuring the time
integral of illuminance of the object.
IEC 68-2-6: 1960, Basic environmental testing pro-
cedures for electrkaI components and electronic In addition, the aperture range and the luminous
- Test F: Vibration. time (flash duration) range are to be indicated, in
equipment - Part 2: Tests
1) Wthin the range of gate time specified by the manufacturer for the specific meter.
2) E,= Exposure value.
---------------------- Page: 3 ----------------------
IS0 10157:1991 (E)
which a measurement of flash light at an IS0 100/21°
6 Calibration
film speed is possible.
6.1 Measuring method
5.2 Gate time
For calibration or for checking the calibration, known
During the gate time both the light of the flash light
exposures are produced and compared with the in-
source and the light of the surroundings (continuous
dication of the flash exposure meter when measur-
light) are to be measured. It is recommended that
ing the light at the same place as the acceptance
the times of the exposure time scale be used in ac-
device of the flash exposure meter.
cordance with IS0 2720. If there is only one fixed
gate time, it must not be less than 0,00781 s and is
to be indicated. If the flash exposure meter does not,
or does not completely, evaluate continuous light,
6.2 Light source
this fact is also to be indicated.
The calibration of flash exposure meters is to be
checked with a light source of the correlated colour
5.3 Storage time
temperature of 5 500 K+ 200 K. It must be possible
to set the duration of the light source, one-tenth of
If the meter incorporates an automatic switching-off
the time value,
to between 0,8 x lo-2 s and
circuit, the storage time shall be long enough so that
3,o x 10-4 s.
the meter indication can be read. The storage time
shall be indicated on the exposure meter or in the
instruction booklet.
6.3 Measuring the light which falls upon the
object
5.4 Addition of individual measurements
(Measuring the object exposure.)
If the measuring values of individual measurements
(Measuring the incident light.)
are or can be added with the flash exposure meter,
the deviation from the sum of
...
SLOVENSKI STANDARD
SIST ISO 10157:2011
01-julij-2011
Fotografija - Svetlomer za bliskavice - Zahteve
Photography - Flash exposure meter - Requirements
Photographie - Exposimètre pour flash - Prescriptions
Ta slovenski standard je istoveten z: ISO 10157:1991
ICS:
37.040.10 Fotografska oprema. Photographic equipment.
Projektorji Projectors
SIST ISO 10157:2011 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
---------------------- Page: 1 ----------------------
SIST ISO 10157:2011
---------------------- Page: 2 ----------------------
SIST ISO 10157:2011
INTERNATIONAL
STANDARD 10157
First edition
1991-06-15
Corrected and reprinted
1991-09-15
Photography - Flash exposure meter -
Requirements
Photographic - Exposimetre pour flash - Prescriptions
Reference number
IS0 10157:1991(E)
---------------------- Page: 3 ----------------------
SIST ISO 10157:2011
IS0 10157:1991(E)
Foreword
IS0 (the International Organization for Standardization) is a worldwide
federation of national standards bodies (IS0 member bodies). 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, govern-
mental and 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 bodies for voting. Publication as an lnter-
national Standard requires approval by at least 75 % of the member
bodies casting a vote.
International Standard IS0 10157 was prepared by Technical Committee
ISO/TC 42, Photography.
Annex A of this International Standard is for information only.
83 IS0 1991
All rights reserved. No part of this publication may be reproduced or utilized in any form
or by any means, electronic or mechanical, including photocopying and microfilm, without
permission in writing from the publisher.
International Organization for Standardization
Case Postale 56 l CH-1211 Geneve 20 l Switzerland
Printed in Switzerland
ii
---------------------- Page: 4 ----------------------
SIST ISO 10157:2011
IS0 10157:1991(E)
INTERNATIONAL STANDARD
- Flash exposure meter - Requirements
Photography
IEC 348: 1971, Safety requirements for electronic
I Scope
measuring apparatus.
This International Standard applies to photoelectric
flash exposure meters which measure the time in- 3 Definitions
tegral of the luminance or of the illuminance of a
photographic object (to be called thereafter For the purposes of this International Standard, the
“object”) illuminated by a source of light for a brief following definitions apply.
l) and indicate the time integral
illumination period
or a number corresponding to the time integral or 3.1 luminance coefficient, 4: The luminance coef-
thefinumber required for the correct exposure of a ficient, 4, is the ratio of the luminance, I,, of the
photographic film with a given speed. sample for a given observation direction to the
illuminance, E, on the sample (q = L/E).
Continuous light, which is available in addition to the
light emitted by the flash light source, is also evalu-
3.2 gate time: The gate time of the measuring cir-
ated.
cuit is the time in which the flash light meter is
measuring.
NOTE 1 If the object is illuminated by electronic flash
equipment with automatic exposure control, the measur-
3.3 storage time: The storage time is that time after
ing results of the flash exposure meter can deviate from
the end of the gate time in which the indicated value
the calibration values of the flash equipment.
changes by Ifi 7 % [corresponding to + l/IO I$*)].
3.4 acceptance angle: See definition in IS0 2720.
2 Normative references
4 Scales
The following standards contain provisions which,
Relative aperture scale, exposure time scale and
through reference in this text, constitute provisions
film speed scale are to be selected in accordance
of this International Standard. At the time of publi-
with IS0 2720.
cation, the editions indicated were valid. All stan-
dards are subject to revision, and parties to
5 General characteristic quantities of the
agreements based on this International Standard
flash exposure meter
are encouraged to investigate the possibility of ap-
plying the most recent editions of the standards in-
dicated below. Members of IEC and IS0 maintain
5.1 Measuring range
registers of currently valid International Standards.
It is recommended that the measuring range be in-
IS0 2720:1974, Photography - General purpose
dicated in candela seconds per square metre when
photographic exposure meters (photoelectric type}
measuring the time integral of luminance of the ob-
- Guide to product specification.
ject and in lux seconds when measuring the time
integral of illuminance of the object.
IEC 68-2-6: 1960, Basic environmental testing pro-
cedures for electrkaI components and electronic In addition, the aperture range and the luminous
- Test F: Vibration. time (flash duration) range are to be indicated, in
equipment - Part 2: Tests
1) Wthin the range of gate time specified by the manufacturer for the specific meter.
2) E,= Exposure value.
---------------------- Page: 5 ----------------------
SIST ISO 10157:2011
IS0 10157:1991 (E)
which a measurement of flash light at an IS0 100/21°
6 Calibration
film speed is possible.
6.1 Measuring method
5.2 Gate time
For calibration or for checking the calibration, known
During the gate time both the light of the flash light
exposures are produced and compared with the in-
source and the light of the surroundings (continuous
dication of the flash exposure meter when measur-
light) are to be measured. It is recommended that
ing the light at the same place as the acceptance
the times of the exposure time scale be used in ac-
device of the flash exposure meter.
cordance with IS0 2720. If there is only one fixed
gate time, it must not be less than 0,00781 s and is
to be indicated. If the flash exposure meter does not,
or does not completely, evaluate continuous light,
6.2 Light source
this fact is also to be indicated.
The calibration of flash exposure meters is to be
checked with a light source of the correlated colour
5.3 Storage time
temperature of 5 500 K+ 200 K. It must be possible
to set the duration of the light source, one-tenth of
If the meter incorporates an automatic switching-off
the time value,
to between 0,8 x lo-2 s and
circuit, the storage time shal
...
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