Olympus i-SPEED 2, Инструкция по эксплуатации

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Understanding ispeed
88
i
--SPEED LT,
i
--SPEED 2
The second method is to use an external electrical trigger, which
causes the camera to stop after a user--settable delay. By
permitting the camera to record for a brief time after the trigger,
some history before the trigger and also some future after the
trigger are preserved in the memory. In this way, the trigger may
occur in the middle of the event of interest and yet the camera can
still capture the whole event.
The delay between the trigger event and the cessation of recording
is controlled by a frame counter known as the trigger counter. The
length of this count is controlled by the menu system and is
expressed as a percentage of the total available record time of the
camera’s memory.
The counter value is described from the viewpoint of the final
recorded video clip, so that a setting of 0% sets the counter to
delay for the entire length of the circular buffer. In this way, the
trigger event will appear at the beginning of the video clip.
Similarly, a setting of 100% will cause the camera to stop
immediately a trigger is received, and this will place the trigger
event at the end of the recorded video clip.
Since the trigger is an electrical signal, the Olympus
i
-- SPEED LT,
i
-- SPEED 2 may be set to wait for either the rising or the falling
edge of the trigger pulse.
The Olympus
i
-- SPEED LT,
i
-- SPEED 2 has two extensions to the
normal trigger operation described above. These are called
Record On Command (ROC) and Burst Record On Command
(BROC) and a description of these follows.
`
ROC, BROC
Record On Command (ROC) and Burst Record On Command
(BROC) are extensions of the normal trigger function of the
Olympus
i
-- SPEED 2. Once Recording mode is selected in ROC
mode, the camera only records video into the memory while the
trigger signal is true (active low). By judicious use of the trigger
connection (e.g. dextrous use of the supplied trigger switch) the
camera may record several short bursts of video into the memory
buffer.
For the purposes of ROC and BROC, the memory is not treated as
a circle, but is regarded as a straight line with a defined start and
end. When the memory is full, no further recording is possible. A
progress indicator is provided.
A facility is provided to erase video bursts from the memory in case
an error is made in the use of the trigger switch. A further facility is
provided to erase the entire memory.