63
Variable frame rate
(continued)
<Notes>
In this unit, the frame rate is set by changing the
storage time of the optical signals sensed by the CCD.
Depending on the frame rate setting, the following
problems may arise.
1
White blemish
White blemishes may be seen on the screen on
account of the fluctuations in the dark current of the
photodiodes which make up the CCD picture
elements.
This current increases in direct
proportion to the rise in the CCD’s temperature and
storage time in the photodiode.
In short, the white blemish increase in inverse
proportion to the frame rate setting.
When a lower frame rate setting is desired, reduce
the master gain setting and, where possible, avoid
direct sunlight and use the unit in a cool
environment.
When using this unit particularly at a low frame rate
of 11 fps or less, the extremely small white streaks
generated by the CCD are minimized using a
special method. For this reason, when subjects
with extremely small bright spots are shot, these
spots may appear less bright.
2
Delayed response time in automatic processing
When the frame rate setting has been lowered, it
takes longer for the unit to perform the automatic
processing (such as auto white balance, flare
compensation, auto knee and auto iris), possibly
giving the user the impression that something is
odd or wrong.
The response time for automatic processes is
particularly slow at a frame rate of 20 fps and
below.
When the frame rate has been set to 20 fps or
below, it is recommended that the unit be operated
with the automatic processing released.
3
Disturbed images
The images may be disturbed for an instant when
shooting while maintaining the frame-to-frame
continuity of the scenes with the time code set to
the rec run mode and with the frame rate set at 24
fps, 25 fps, 30 fps or 50 fps.
This occurs in order to reset the video signals from
the camera so as to maintain the continuity of the
time code recorded on the tape.
The disturbed images are not recorded on the tape
but they will affect the signals which are output from
the HD SDI MON connector.
Similarly, the images may also be disturbed for an
instant when the time code has been locked to
external signals or preset while the frame rate is set
at 24 fps, 25 fps, 30 fps or 50 fps.
If the time code has been set to the free run mode,
the images may also be disturbed at that instant
when the frame rate is switched to 24 fps, 25 fps,
30 fps or 50 fps.
However, the images will not be disturbed
during recording even if the frame rate is
switched to 24 fps, 25 fps, 30 fps or 50 fps.
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