SIST EN 61146-4:1999

Video cameras (PAL/SECAM/NTSC) - Methods of measurement -- Part 4: Automatic functions of video cameras and camera-recorders

Limited to automatic functions relating to light input from teh lens and to the electronic output from videio cameras and the video camera portions of camera recorders. Defines test patterns, measurement conditions, methods of measurement and the presentation of measured results so as to make possible the comparison of the measurement results.

Videokameras (PAL/SECAM/NTSC) - Meßverfahren -- Teil 4: Automatische Funktionen von Videokameras und Camcordern

Caméras vidéo (PAL/SECAM/NTSC) - Méthodes de mesure -- Partie 4: Fonctions automatiques des caméras video et des caméscopes

Se limite aux fonctions automatiques qui sont en rapport avec la quantité de lumière entrant par l'objectif et avec la sortie électronique de la caméra vidéo et des parties caméra vidéo des caméscopes. Définit les mires d'essai, les conditions de mesure, les méthodes de mesure et la présentation des résultats obentus de façon à rendre possible la comparaison entre les résultats de mesure.

Video cameras (PAL/SECAM/NTSC) - Methods of measurement -- Part 4: Automatic functions of video cameras and camera-recorders (IEC 61146-4:1998)

General Information

• Status: Published
• Publication Date: 31-Mar-1999
• ICS: 33.160.40 - Video systems
• Technical Committee: AVM - Audio, video and multimedia systems and equipment
• Current Stage: 6060 - National Implementation/Publication (Adopted Project)
• Start Date: 01-Apr-1999
• Due Date: 01-Apr-1999
• Completion Date: 01-Apr-1999
• Ref Project: EN 61146-4:1998 - Video cameras (PAL/SECAM/NTSC) - Methods of measurement - Part 4: Automatic functions of video cameras and camera-recorders

Standards Content (Sample)

SLOVENSKI STANDARD
SIST EN 61146-4:1999
01-april-1999
Video cameras (PAL/SECAM/NTSC) - Methods of measurement -- Part 4: Automatic
functions of video cameras and camera-recorders (IEC 61146-4:1998)
Video cameras (PAL/SECAM/NTSC) - Methods of measurement -- Part 4: Automatic
functions of video cameras and camera-recorders
Videokameras (PAL/SECAM/NTSC) - Meßverfahren -- Teil 4: Automatische Funktionen
von Videokameras und Camcordern
Caméras vidéo (PAL/SECAM/NTSC) - Méthodes de mesure -- Partie 4: Fonctions
automatiques des caméras video et des caméscopes
Ta slovenski standard je istoveten z: EN 61146-4:1998
ICS:
33.160.40 Video sistemi Video systems
SIST EN 61146-4:1999 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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NORME
CEI
INTERNATIONALE
IEC
61146-4
INTERNATIONAL
Première édition
STANDARD
First edition
1998-05
Caméras vidéo (PAL/SECAM/NTSC) –
Méthodes de mesure –
Partie 4:
Fonctions automatiques des caméras vidéo
et des caméscopes
Video cameras (PAL/SECAM/NTSC) –
Methods of measurement –
Part 4:
Automatic functions of video cameras and
camera-recorders
 IEC 1998 Droits de reproduction réservés  Copyright - all rights reserved
Aucune partie de cette publication ne peut être reproduite ni No part of this publication may be reproduced or utilized in
utilisée sous quelque forme que ce soit et par aucun any form or by any means, electronic or mechanical,
procédé, électronique ou mécanique, y compris la photo- including photocopying and microfilm, without permission in
copie et les microfilms, sans l'accord écrit de l'éditeur. writing from the publisher.
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Telefax: [phone] e-mail: [e-mail] IEC web site http: //www.iec.ch
CODE PRIX
Commission Electrotechnique Internationale
PRICE CODE R
International Electrotechnical Commission
Pour prix, voir catalogue en vigueur
For price, see current catalogue

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61146-4 © IEC:1998 – 3 –
CONTENTS
Page
FOREWORD . 7
Clause
1 Scope . 9
2 Normative references. 9
3 Terms and definitions . 9
4 Conditions . 11
4.1 Environmental conditions. 11
4.2 Conditions of measurement. 11
4.2.1 Illumination. 11
4.2.2 Shooting conditions. 11
4.2.3 Settings of the equipment under test. 11
4.2.4 Reliability of measured results . 13
5 Method of measurement of automatic functions. 13
5.1 Automatic exposure control. 13
5.1.1 Dependency on illumination level . 13
5.1.2 Dependency on average brightness . 17
5.1.3 Dynamic response. 23
5.2 Automatic focusing . 25
5.2.1 Assessment of focusing response time . 25
5.2.2 Focusing accuracy. 27
5.3 Automatic white balance . 29
5.3.1 Dependency on colour temperature of illumination . 29
5.3.2 Dynamic characteristics of automatic white balance . 35
Annex A (normative) Specification of the tracking chart. 39
Figure 1 – Equipment arrangement for measurement of dependency on illumination level 15
Figure 2 – Equipment arrangement for measurement of dependency on average brightness 19
Figure 3 – Waveform of a horizontal line for B = 27 %. 21
Figure 4 – Waveform of a horizontal line for B = 77 %. 21
Figure 5 – Waveform of a horizontal line for B = 9 % . 21
Figure 6 – Typical response (1). 23
Figure 7 – Typical response (2). 23
Figure 8 – Equipment arrangement for measurement of focusing time. 25
Figure 9 – Equipment arrangement for measurement of automatic white balance. . 31
Figure 10 – Colour temperature conversion block and its specification . 33
Figure A.1 – Dimensional specification of the large-sized tracking chart . 39

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61146-4 © IEC:1998 – 5 –
Page
Table 1 – Automatic exposure control – Dependency on illumination level . 17
Table 2 – Automatic exposure control – Dependency on average brightness . 23
Table 3 – Automatic focusing – Assessment of focusing response time. 27
Table 4 – Automatic white balance – Dependency on colour temperature of illumination . 35
Table 5 – Optical filters used for conversion of colour temperature. 37
Table A.1 – Positions of equi-centred small circles and triangle markers . 39

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61146-4 © IEC:1998 – 7 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
___________
VIDEO CAMERAS (PAL/SECAM/NTSC) –
METHODS OF MEASUREMENT –
Part 4: Automatic functions of video cameras
and camera-recorders
FOREWORD
1) The IEC (International Electrotechnical Commission) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of the IEC is to promote
international cooperation on all questions concerning standardization in the electrical and electronic fields. To
this end and in addition to other activities, the IEC publishes International Standards. Their preparation is
entrusted to technical committees; any IEC National Committee interested in the subject dealt with may
participate in this preparatory work. International, governmental and non-governmental organizations liaising
with the IEC also participate in this preparation. The IEC collaborates closely with the International Organization
for Standardization (ISO) in accordance with conditions determined by agreement between the two
organizations.
2) The formal decisions or agreements of the IEC on technical matters express, as nearly as possible, an
international consensus of opinion on the relevant subjects since each technical committee has representation
from all interested National Committees.
3) The documents produced have the form of recommendations for international use and are published in the form
of standards, technical reports or guides and they are accepted by the National Committees in that sense.
4) In order to promote international unification, IEC National Committees undertake to apply IEC International
Standards transparently to the maximum extent possible in their national and regional standards. Any
divergence between the IEC Standard and the corresponding national or regional standard shall be clearly
indicated in the latter.
5) The IEC provides no marking procedure to indicate its approval and cannot be rendered responsible for any
equipment declared to be in conformity with one of its standards.
6) Attention is drawn to the possibilty that some of the elements of this International Standard may be the subject
of patent rights. The IEC shall not be held responsible for identifying any or all such patent rights.
International Standard IEC 61146-4 has been prepared by subcommittee 100C: Audio, video
and multimedia subsystems and equipment, of IEC technical committee 100: Audio, video and
multimedia systems and equipment.
The text of this standard is based on the following documents:
FDIS Report on voting
100C/221/FDIS 100C/227/RVD
Full information on the voting for the approval of this standard can be found in the report on
voting indicated in the above table.
Annex A forms an integral part of this standard.

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61146-4 © IEC:1998 – 9 –
VIDEO CAMERAS (PAL/SECAM/NTSC) –
METHODS OF MEASUREMENT –
Part 4: Automatic functions of video cameras
and camera-recorders
1 Scope
This part of IEC 61146 applies to the assessment of characteristics of automatic functions
which are implemented in colour video cameras and camera-recorders. The performance to be
assessed in this standard is limited to automatic functions relating to light input from the lens
and to the electronic output from video cameras and the video camera portions of camera-
recorders.
This standard defines test patterns, measurement conditions, methods of measurement and
the presentation of measured results so as to make possible the comparison of the
measurement results.
This standard intends to provide an objective method of measurement for each characteristic
of the automatic functions but the results of objective measurements may not correlate well
with the subjective assessment of automatic functions.
It does not specify limiting values for the various characteristics related to automatic functions.
2 Normative references
The following normative documents contain provisions which, through reference in this text,
constitute provisions of this part of IEC 61146. At the time of publication, the editions indicated
were valid. All normative documents are subject to revision, and parties to agreements based
on this part of IEC 61146 are encouraged to investigate the possibility of applying the most
recent editions of the normative documents listed below. Members of IEC and ISO maintain
registers of currently valid International Standards.
IEC 61146-1:1994, Video cameras (PAL/SECAM/NTSC) – Methods of measurement – Part 1:
Non-broadcast single-sensor cameras
ISO 8341:1989, Photography – Slide projectors and filmstrip projectors – Illumination test
3 Terms and definitions
For the purpose of this part of IEC 61146, the following definitions apply.
3.1
grey scale chart
test chart which has logarithmic grey steps of γ = 2,2 specified in item 1 of annex A of
IEC 61146-1

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61146-4 © IEC:1998 – 11 –
3.2
tracking chart
test chart with a radial arrangement of black and white wedges (see annex A)
3.3
resolution chart
test chart specified in item 4 of annex A of IEC 61146-1
3.4
uniform white chart
test chart specified in item 2 of annex A of IEC 61146-1
3.5
equipment under test
colour video camera and camera-recorder with electronic output(s)
4 Conditions
4.1 Environmental conditions
All measurements shall be carried out within the environmental conditions as specified by the
manufacturer.
The environmental conditions during measurement, at least the temperature and the relative
humidity, shall be reported together with the presentation of the measurement results.
4.2 Conditions of measurement
4.2.1 Illumination
a) The illumination of test charts should be performed by two or four spot lights depending on
the characteristics to be measured.
b) The correlated colour temperature of the spot light shall be 3 100 K ± 100 K.
c) Unless otherwise specified, the illumination level of the test chart shall be 2 000 lx ± 100 lx.
d) The non-uniformity of the illumination shall be less than 5 %.
e) The methods used for all the measurements shall be in line with the standard methods
specified in ISO 8341.
4.2.2 Shooting conditions
a) An optical axis of the equipment under test shall coincide with a normal line of the test
chart.
b) Unless otherwise specified, the distance between the test chart and the equipment under
test should be approximately 2 m.
c) Unless otherwise specified, the zooming should be adjusted so that horizontal and vertical
markers just fit the full frame of an under-scan monitor.
4.2.3 Settings of the equipment under test
Except when otherwise indicated, the following setting shall be used:
a) focus shall be adjusted for the best condition;

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61146-4 © IEC:1998 – 13 –
b) white balance shall be adjusted automatically or manually for a correlated colour
temperature of 3 100 K ± 100 K;
c) iris control of the lens may be automatic or manual;
d) gain control may be automatic or manual.
4.2.4 Reliability of measured results
The reliability and repeatability of measured results may be affected by the automation
processes incorporated in the equipment under measurement. Some automatic functions may
exhibit instability. Therefore, averaging of data obtained by multiple measurement may be
necessary if additional precision is required.
5 Method of measurement of automatic functions
5.1 Automatic exposure control
5.1.1 Dependency on illumination level
5.1.1.1 Characteristics to be measured
Dependency of absolute luminance signal levels and their relative deviation on illumination
level.
5.1.1.2 Measurement conditions
The measurements shall be conducted using the grey scale chart of γ = 2,2. The equipment
arrangement shall be as shown in figure 1.

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61146-4 © IEC:1998 – 15 –
Lamp
10 000 lx
Equipment
under
test
Neutral density filter
Test chart
Lamp
Terminated by 75 Not terminated
Ω
Oscilloscope
Under-scan monitor
IEC  724/98
Figure 1 – Equipment arrangement for measurement of dependency on illumination level
5.1.1.3 Method of measurement
a) The test chart illuminated with 10 000 lx by lamps having a correlated colour temperature of
3 100 K ± 100 K shall be imaged to fill the full screen.
b) The luminance signal level (corresponding to a white part at the centre of the test chart)
Y
relative to the blanking level shall be measured with an oscilloscope. The measurements
shall be conducted with the following densities of neutral density optical filters placed in
D
front of the lens:
– = 0,0 (effective illumination of 10 000 lx);
D
– D = 0,7 (effective illumination of 2 000 lx);
– = 1,4 (effective illumination of 400 lx);
D
– D = 2,1 (effective illumination of 80 lx).
c) The measured results are noted as Y , Y , Y and Y .
10 000 2 000 400 80

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61146-4 © IEC:1998 – 17 –
d) The dependency of luminance signal level on the illumination level shall be calculated by
the following equation:
 
Y
n
 
R=− 1 × 100 %
n
 
Y
 2 000 
where n = 10 000, 400 and 80.
5.1.1.4 Presentation of results
The absolute luminance signal levels and their relative deviations shall be reported as in
table 1.
Table 1 – Automatic exposure control – Dependency on illumination level
10 000 lx 2 000 lx 400 lx 80 lx
Absolute level (mV) Y Y Y Y
10 000 2 000 400 80
Relative deviation (%) R 0 R R
10 000 400 80
NOTE – Measured results will not directly relate to a practical automatic function. The result should be
understood as showing a tendency of the equipment under test.
5.1.2 Dependency on average brightness
5.1.2.1 Characteristics to be measured
Luminance signal level and its relative deviation as a function of average brightness of
shooting target.
5.1.2.2 C
...