Sony SRW-9000 Operation Manual page 98

for editing or other post-processing in 1080/
23.98PsF format.
Relation between the target frame
frequency and the number of frames shot
To obtain the desired slow and quick motion
effects, it is necessary to set the appropriate
number of frames according to the target frame
frequency. To obtain quick motion effects, shoot
with undercranking. To obtain slow motion
effects, shoot with overcranking.
Example at the target frame frequency of
23.98PsF
To obtain quick motion effects: Set the number
of frames to 1 to 23 FPS.
To obtain slow motion effects: Set the number of
frames to 25 to 60 FPS.
For example, shooting at 60 FPS causes playback
in slow motion at 0.4 times normal playback
speed.
Number of frames
FPS
60
30
Target frame
frequency:
23.98PsF
1
Relation between the target frame
frequency and timecode
When the system frequency is 23.98 Hz,
timecode normally advances from 0 to 23 frames.
This becomes the timecode of the recorded
material (target frame frequency). If the rate at
which timecode advances is not constant within
the recorded material, a timecode discontinuity
occurs at playback time. For this reason, set the
target frame rate at recording time to the same
value as the timecode at playback time.
98 Overview
(Frames/second)
Slow motion
24 FPS
Normal
speed
playback
Quick motion
In SR Motion shooting, it is possible to set the
target frame frequency and the system frequency
at recording time to different values. For
example, if 60 frames are recorded with the target
frame frequency set to 23.98 Hz and the system
frequency set to 59.94 Hz, then 60 frames per
second are recorded, but the timecode does not
advance from 0 to 59 frames. Instead, it advances
from 0 to 23 frames, which matches the target
frame frequency. If one second is recorded with
these settings, beginning with second 00 frame
00, then the timecode advances quickly from
second 00 frames 00 to 23, and then continues to
advance as second 01 frames 00 to 23, and finally
as second 02 frames 00 to 11, at which point 60
frames have been recorded (see the following
figure).
When a tape recorded in this way is played on a
VTR that has been set to a system frequency of
23.98 Hz (the tape is played at a target frame
frequency of 23.98PsF), then the video is 24/60 =
0.4 times normal speed. But the timecode
advance by one second in the space of one
second. Even if the slow-motion section follows a
section recorded at normal speed, the playback
timecode is continuous and no discontinuity
occurs.