SIST EN 61146-3:1999

Video cameras (PAL/SECAM/NTSC) - Methods of measurement -- Part 3: Non-broadcast camera-recorders

Concerns the assessment of the performance of non-broadcast camera-recorders. Defines test patterns and measurement conditions so as to enable the comparison of the results of measurements.

Videokameras (PAL/SECAM/NTSC) - Meßverfahren -- Teil 3: Kamerarecorder für den Gebrauch außerhalb des Rundfunks

Caméras vidéo (PAL/SECAM/NTSC) - Méthodes de mesure -- Partie 3: Caméscopes hors de la radiodiffusion

Concerne l'évaluation des performances des caméscopes couleur hors de la radiodiffusion. Définit les mires d'essai et les conditions de mesure de façon à permettre la comparaison des résultats.

Video cameras (PAL/SECAM/NTSC) - Methods of measurement -- Part 3: Non-broadcast camera-recorders (IEC 61146-3:1997)

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 61146-3:1997 - Video cameras (PAL/SECAM/NTSC) - Methods of measurement - Part 3: Non-broadcast camera-recorders

Standards Content (Sample)

SLOVENSKI STANDARD
SIST EN 61146-3:1999
01-april-1999
Video cameras (PAL/SECAM/NTSC) - Methods of measurement -- Part 3: Non-
broadcast camera-recorders (IEC 61146-3:1997)
Video cameras (PAL/SECAM/NTSC) - Methods of measurement -- Part 3: Non-
broadcast camera-recorders
Videokameras (PAL/SECAM/NTSC) - Meßverfahren -- Teil 3: Kamerarecorder für den
Gebrauch außerhalb des Rundfunks
Caméras vidéo (PAL/SECAM/NTSC) - Méthodes de mesure -- Partie 3: Caméscopes
hors de la radiodiffusion
Ta slovenski standard je istoveten z: EN 61146-3:1997
ICS:
33.160.40 Video sistemi Video systems
SIST EN 61146-3:1999 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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NORME
CEI
INTERNATIONALE
IEC
61146-3
INTERNATIONAL
Première édition
STANDARD
First edition
1997-07
Caméra vidéo (PAL/SECAM/NTSC) –
Méthodes de mesure –
Partie 3:
Caméscopes hors de la radiodiffusion
Video cameras (PAL/SECAM/NTSC) –
Methods of measurements –
Part 3:
Non-broadcast camera-recorders
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Pour prix, voir catalogue en vigueur
For price, see current catalogue

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61146-3 © IEC:1997 – 3 –
CONTENTS
Page
FOREWORD . 7
INTRODUCTION. 9
Clause
1 General. 11
1.1 Scope. 11
1.2 Normative references. 11
1.3 Conditions. 13
2 Video characteristics of the complete unit. 15
3 Video characteristics related to the camera part only . 17
4 Other anomalies due to the recorder section . 17
4.1 Chrominance to luminance intermodulation (PAL/NTSC) . 17
4.2 Luminance to chrominance crosstalk and moirés . 19
4.3 Luminance to chrominance displacement . 21
4.4 Assembly edit system . 23
4.5 Insert edit system. 29
4.6 Tape damage in pause mode. 29
5 Time base. 29
6 Audio characteristics. 29
6.1 Signal-to-noise ratio (automatic gain control (AGC) on). 29
6.2 Amplitude/frequency response. 31
6.3 Harmonic distortion. 33
6.4 Wow and flutter. 33
6.5 AGC operation range and hold time . 33
6.6 Directional response of the microphone . 35
6.7 Audio dub or insert quality (audio hole) . 37
6.8 Hi-fi audio tracking accuracy.41
6.9 Audio FM recording . 43
7 Viewfinder screen luminance . 43
8 Automatic system and others. 43
8.1 Automatic exposure. 43
8.2 Automatic focusing. 43
9 Classification. 43
9.1 General. 43
9.2 Classification of the characteristics to be specified . 45

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61146-3 © IEC:1997 – 5 –
Page
Figures
1 Chrominance to luminance intermodulation (PAL/NTSC). 47
2 Luminance to chrominance crosstalk and moirés. 47
3 Subcarrier band-pass filter characteristics . 49
4 Output signal of band-pass filter. 49
5 Luminance to chrominance displacement. 51
6 Block diagram of the circuit arrangement for video timing of the edit system. 57
7 Frame timing of the start time . 57
8 Frame timing of the overwrite frame number (1). 59
9 Frame timing of the overwrite frame number (2). 59
10 Circuit arrangement for measurement of audio characteristics . 61
11 Amplitude/frequency response. 61
12 Circuit arrangement for measurement of signal-to-noise ratio (AGC on). 63
13 Circuit arrangement for measurement of AGC operation range and hold time. 65
14 Curve showing output level as a function of input level. 65
15 Hold time . 67
16 Directional response of the microphone. 67
17 Polar diagram of microphone sensitivity. 69
18 Block diagram of test system . 69
19 Timing chart of the hole or the overlap at a record pause or insert point. 71
20 Timing chart of the hole or the overlap at the insertion and the dubbed point . 71
21 Circuit arrangement for measurement of hi-fi audio tracking accuracy. 73
22 Time difference between the video and audio signals . 73
Annex A – Bibliography . 75

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61146-3 © IEC:1997 – 7 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
_________
VIDEO CAMERAS (PAL/SECAM/NTSC) –
METHODS OF MEASUREMENT –
Part 3: Non-broadcast 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 co-operation 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 possibility 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 61146-3 has been prepared by subcommittee 100B: Recording, 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
100B/52/FDIS 100B/92/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.
IEC 61146 consists of the following parts, under the general title Video cameras (PAL/SECAM/
NTSC) – Methods of measurement
Part 1: Non-broadcast single-sensor cameras
Part 2: Two and three sensor professional cameras
Part 3: Non-broadcast camera-recorders
Part 4: Automatic functions of video cameras and camera recorders
Annex A is for information only.

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61146-3 © IEC:1997 – 9 –
INTRODUCTION
A camera-recorder is a combination of several devices, such as a video camera, video
recorder, microphone and an electronic or through-the-lens (TTL) viewfinder. The appropriate
measurements should be adopted for the following cases:
a) The camera section only is used as a video camera in the monitoring mode. The
methods of measurement should be in accordance with IEC 61146-1.
b) The camera-recorder has both a playback capability and an audio-video micro-
phone/camera output, which may be electronics-to-electronics (E to E), passing through the
recorder, but not recorded on the tape. Audio and video inputs may, or may not, be
provided. The methods of measurement of all characteristics of the complete unit should be
in accordance with this standard.
c) The camera-recorder has no playback facility. The tape containing the test signals is
played back on a high quality calibrated player. Measurements are made on the playback
signal in accordance with this standard.

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61146-3 © IEC:1997 – 11 –
VIDEO CAMERAS (PAL/SECAM/NTSC) –
METHODS OF MEASUREMENT –
:
Part 3 Non-broadcast camera-recorders
1 General
1.1 Scope
The measuring methods described in this part of IEC 61146 concern the assessment of the
performance of non-broadcast camera-recorders (NTSC/PAL/SECAM). The appropriate
measurements are to be applied according to whether the camera-recorder has a tube or semi-
conductor camera. In the case of a camera-recorder without playback capability, the details of
the separate player used for the measurements shall be stated. In this standard, the
characteristics apply to the camera-recorder as a complete entity.
This standard defines test patterns and measurement conditions so as to enable the
comparison of the results of measurements. The standard does not specify limiting values for
the various quantities for acceptable performances, since that is not the object of this standard.
The methods of measurement are designed to enable the assessment of the performance of
the camera-recorder by using the lens for input and any available output from the device (e.g.
separate luminance and chrominance signals or composite signal output).
1.2 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 edition of the normative documents indicated below. Members of IEC and ISO maintain
registers of currently valid International Standards.
IEC 60068-1: 1988, Environmental testing – Part 1: General and guidance
IEC 60107-1: 1977, Recommended methods of measurement on receivers for television broad-
cast transmissions – Part 1: General considerations – Electrical measurements other than
those at audio-frequencies
IEC 60268-1: 1985, Sound system equipment – Part 1: General
IEC 60268-4: 1972, Sound system equipment – Part 4: Microphones
IEC 60268-8: 1973, Sound system equipment – Part 8: Automatic gain control devices
IEC 60386: 1972, Method of measurement of speed fluctuations in sound recording and
reproducing equipment
IEC 60735: 1991, Measuring methods for video tape properties
IEC 60756: 1991, Non-broadcast video tape recorders – Time base stability
IEC 61041-1: 1990, Non-broadcast video tape recorders – Methods of measurement – Part 1:
General video (NTSC/PAL) and audio (longitudinal) characteristics
IEC 61041-2: 1994, Non-broadcast video tape recorders – Methods of measurement – Part 2:
Video characteristics chrominance SECAM
IEC 61041-3: 1993, Non-broadcast video tape recorders – Methods of measurement – Part 3:
Audio characteristics for FM recording
IEC 61146-1:1994, Video cameras (PAL/SECAM/NTSC) – Methods of measurement – Part 1:
Non-broadcast single-sensor cameras

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61146-3 © IEC:1997 – 13 –
1.3 Conditions
1.3.1 Environmental conditions
All measurements shall be carried out within the environmental conditions specified by the
manufacturer. The ambient temperature and relative humidity during testing shall be noted with
the test results. Other details of the test environment may be included if relevant. The
recommended ambient temperature is 20 °C ± 2 °C according to IEC 60068-1. An adequate
warm-up time shall be allowed.
1.3.2 Performance of measurement
Unless otherwise stated, the measurements shall be carried out as follows.
Measurements of the performance of the complete unit shall be made on the playback signal
from the recorder section immediately after recording, on the same unit if it has playback
capability. Where a camera output is available, the camera should be set to the optimum
conditions before making the test recording. Where no camera output is available, it may be
necessary to make a series of recordings at different camera settings to establish optimum
settings for the camera before making the test recording.
Measurements related to camera performance only are assumed not to be affected by the
recorder section. These measurements shall be made on the camera output signal only. Where
no camera output is available, the measurements shall be made by recording the camera
signals on the video tape and making the measurements on the playback signal.
The above-mentioned measurements shall be made when the camera is shooting the test chart
appropriate to the characteristic to be measured. Each test pattern used shall be specified,
together with the lighting conditions (illumination intensity, correlated colour temperature, etc.).
Automatic measurement methods are under development and consideration.
1.3.3
Conditions of shooting
Unless otherwise stated the conditions shall be as follows.
The subject illumination of a reflective test chart shall be 2 000 lx ± 5 %. The luminance of a

2
transparent test chart, at peak white, shall be 636 cd/m ± 5 %. The non-uniformity of the
subject illumination shall be less than 5 %. The correlated colour temperature of the light
source shall be 3 100 K ± 100 K. The white balance of the unit under test shall be set manually
or automatically to 3 100 K ± 100 K. The test chart shall be shot by the camera so that the
frame delineated by the arrows exactly coincides with the edges of the picture displayed on the
video monitor in underscan mode.
The focus control shall be in auto or manual mode with optimum focus setting. The iris control
shall be in auto or manual mode. In order to obtain the desired exposure level, it may be
advantageous to add an illuminated white card or a black area, and also to adjust the lens
zoom, so that the measurement is not dependent on exactly filling the screen to the arrows of
the test chart.
The gain control, if any, shall be set to "0 dB" gain. The optical filter, if any, shall be set to
"open position".
1.3.4 Reference conditions
For the measurement of the camera performance, the reference luminance level on the camera
output is assumed to be 700 mV peak-to-peak for PAL and SECAM systems, and 714 mV
peak-to-peak for the NTSC system (from blanking level to peak white). In playback mode, each
camera-recorder has its own individual output level; thus the audio and video output levels
specified for the equipment under test are used as the reference levels. A gray scale chart and
a specified audio signal shall be used to obtain a consistent reference level.

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61146-3 © IEC:1997 – 15 –
1.3.5 Magnetic tape
The type of magnetic tape used for measurement shall be commonly available and stated,
together with the results of measurement.
NOTES
1 The type of magnetic tape recommended by the manufacturer of the unit under test is assumed to be
available.
2 If a reference tape is available, a test of the playback section should be made to verify the main perform-
ance characteristics (output level, amplitude/frequency response, distortions, time base errors). This verification
procedure should be implemented on the separate player used if the unit under test has no playback facility.
1.3.6 Audio measurements
All measurements shall be made in an anechoic room using the circuit arrangements shown in
figures 10, 12, 13, 15, 16, 18, and 21.
The rated output level shall be as specified by the manufacturer of the equipment under test.
2 Video characteristics of the complete unit
The measurement of these characteristics shall be performed in accordance with IEC 61146-1,
figure 1 of IEC 61041-1 and IEC 61041-2 (as appropriate) by measuring the video playback
signal. Several recordings may have to be made to arrive at the appropriate camera
adjustments and illumination level to yield the required playback signal.
The measurements for the following characteristics are described in the clauses listed in
following table.
IEC 61041-1
IEC 61146-1
Parameters to be measured or
Clause
IEC 61041-2
Subclause
2.1 Luminance sensitivity 4
2.2 Luminance resolution 5
2.3 Luminance signal-to-noise ratio 6
2.4 Luminance amplitude/frequency response 7
2.5 Luminance waveform distortions 8
2.6 Luminance gamma characteristics and non-linearity 9
2.7 Luminance drop-out compensation 2.8
2.8 Luminance white clipping and compression rate 10
2.9 Luminance dynamic range and contrast range 11
2.10 Luminance white non-uniformity 12
2.11 Chrominance signal-to-noise ratio 13
2.12 Chrominance amplitude/frequency response 14
2.13 White and black balance 15
2.14 Colour and white reproduction non-uniformity 16
2.15 Grey-scale non-purity (white tracking error) 17
2.16 Colour reproduction 18
2.17 Luminance and chrominance moirés 19

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61146-3 © IEC:1997 – 17 –
3 Video characteristics related to the camera part only
The measurement of these characteristics shall be performed according to IEC 61146-1 by
measuring the camera output signal. If no camera output is available, the video playback signal
shall be measured. In this case, several recordings may be necessary to arrive at the
appropriate adjustment of the camera and/or illumination.
The number of the relevant clauses of IEC 61146-1 are given in brackets.
3.1 (20) Lag
3.2 (21) Sticking (image retention)
3.3 (22) Blooming
3.4 (23) Smearing
3.5 (24) Geometric distortions
4 Other anomalies due to the recorder section
4.1 Chrominance to luminance intermodulation (PAL/NTSC)
4.1.1 Characteristics to be specified
The degree of intermodulation between the luminance FM carrier and the down-converted
chrominance carrier, being demodulated as unwanted luminance signal. The frequencies of
these unwanted signals are f and 2 f , where f is the frequency of the down-converted
c c c
chrominance carrier.
4.1.2 Method of measurement
The circuit arrangement and the test pattern shall be as shown in figure 1. The test pattern
shall be a uniform white pattern which shall be shot through a red colour filter (Kodak Wratten
No. 25). The conditions for shooting shall be those specified in 1.3. The values V r.m.s. of the
amplitudes of the intermodulation signals, having frequencies f and 2 f , shall be measured by
c c
a spectrum analyzer, during playback of the tape section where the test pattern has been
recorded. The spectrum analyzer shall be preceded by a gating circuit to select only the signal
during the flat portion of the 50 % grey level. The gating circuit shall be followed by a low-pass
filter that attenuates the spectral components of the composite video.
The low-pass filter shall have a nominal cut-off frequency of 2,8 MHz (–3 dB). The colour sub-
carrier frequency f shall be suppressed by 40 dB. The IF bandwidth of the spectrum analyzer
sc
shall be 30 kHz. It is recommended that a digitizing spectrum analyzer is used in the "maximum
hold" mode. The reference level V shall be the amplitude of the 100 % white output picture
ref
signal, i.e. from blanking level to white level. The intermodulation ratio IM is defined as the ratio
of the reference level to the peak-to-peak amplitude of the intermodulation signal, expressed in
decibels.
a) If the chroma level is within 100 % ± 15 %, the intermodulation IM shall be calculated by
means of the formula:
V
ref
IM=−20 lg 9 (dB)
V
rms
In practice, it is difficult to obtain an input chroma level of 100 % and input luminance level
of 50 %, because each camera-recorder has a different initial level of chroma and
luminance, and also a different iris control system. However differences in luminance level
(40 % to 80 %) strongly influence the intermodulation measurement.

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61146-3 © IEC:1997 – 19 –
b) If the input chroma level is other than 100 % ± 15 %, two types of pattern (having different
saturations) shall be shot to obtain two different chroma levels between 50 % and 120 %. In
principle, the phase of the colour signal has no effect on the intermodulation. The
intermodulation IM at the input chroma level of 100 % shall be calculated according to the
linear relation, that is:
V ×100
ref
IM = 20 lg −9(dB)
VV×
rms c
where
V is the input chroma level, expressed as a percentage.
c
These measurements shall be made while reproducing the previously recorded test signal.
4.1.3 Presentation of results
The measurement results shall be expressed as follows:
– the intermodulation ratio IM in decibel for f and 2 f ;
c c
– the input chrominance level as a percentage;
– the input luminance level as a percentage;
– the type of video tape used for the measurement.
4.2 Luminance to chrominance crosstalk and moirés
4.2.1 Characteristics to be specified
This measurement determines the degree of crosstalk of FM luminance sidebands into the
down-converted chrominance band, being demodulated as unwanted colour signals (so-called
cross colour) in the VTR part (see IEC 61041-1 or IEC 61041-2 as appropriate). Also the
degree of moirés being produced by the alias phenomena due to the discrete sampling in the
camera part (see clause 19 of IEC 61146-1).
4.2.2 Methods of measurement
The circuit arrangement shall be as shown in figure 2. The test pattern shall be a radial
resolution chart with a red colour area in the centre. This red colour shall correspond to that of
the CIE colour chips (Munsell notation: 4,5. R 4/13). The conditions of shooting shall be those
mentioned in 1.3.3.
The following measurements shall be made using a vectorscope: the amplitude of the red
vector shall be measured and taken as V (see figure 2). The greatest amplitude of the colour
ref
beat signal V appearing around the cross point of the vectorscope axes. The amplitude V
LC LC
of the colour beat signal shall be compared to the amplitude V of the red vector in order to
ref
derive the degree of luminance to chrominance crosstalk LC.
V
LC
LC = 20 lg (dB)
V
ref
NOTE – Some transients may be visible on the vectorscope screen due to the luminance components. They
should be ignored for this measurement.

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61146-3 © IEC:1997 – 21 –
4.2.3 Presentation of results
The resulting measurements shall be reported in decibels as luminance to chrominance
crosstalk in playback mode of the previously recorded test signal.
4.2.4 Alternative method PAL/NTSC
Subclauses 4.2.1, 4.2.2, and 4.2.3 shall apply for this method. The chrominance signal shall be
separated from the composite signal by means of a band-pass filter with the characteristics
shown in figure 3. The output signal from the band-pass filter shall be measured by an
oscilloscope (see figure 4).
The reference level V shall be the peak-to-peak amplitude of the signal corresponding to
ref
the red colour of the test pattern (see figure 2). The peak-to-peak amplitude of the colour
beats V appearing in the remaining area of the pattern shall be compared to the reference
LC
level V in order to derive the degree of luminance to chrominance crosstalk LC.
ref
V
LC
LC = 20 lg (dB)
V
ref
Presentation of results for the alternative method shall be as in 4.2.3
4.3 Luminance to chrominance displacement
4.3.1 Characteristics to be specified
The timing difference (Y/C delay) between the luminance and chrominance channels. The
timing difference shall be measured between the 50 % amplitude points on the luminance and
chrominance transitions, both signals deriving from the same test pattern.
4.3.2 Method of measurement for PAL/NTSC
The circuit arrangement shall be as shown in figure 5. The test pattern for this measurement
shall be a cross pattern (like the "Red Cross" symbol) of 75 % saturated green or yellow colour
surrounded by a grey field of approximately 20 % reflectance/transmittance (see figure 5). A
calibrated demodulator shall be used to provide the luminance signal E'Y and the chrominance
signals E'(R-Y) and E'(B-Y). A dual trace oscilloscope shall be used to measure the time
difference. The Y/C delay of the demodulator shall be measured and reported in the
presentation of results.
Y/C delay in horizontal direction
The line M shall be selected (see figure 5, 5a, 5b) and magnified on the oscilloscope as shown
in figures 5d and 5e. The time difference t in nanoseconds shall be measured between the
dH
50 % level points. If the luminance Y and chrominance CH sign
...