Olympus i-SPEED 2, Instructions Manual

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Understanding ispeed
89
i
--SPEED LT,
i
--SPEED 2
BROC is an extension of ROC, in that a trigger edge (rather than
an active level) will cause the camera to record video for a
pre--defined time. The length of time that the trigger signal is active
is ignored. This function is especially useful for unattended
operation when several short events are likely to occur. The burst
time is settable in the menu system.
`
Sensor, FPN, FPN Calibration
The image sensor used in the Olympus
i
-- SPEED LT,
i
-- SPEED 2
camera is a CMOS chip and, like all CMOS imagers, it has the
property of introducing fixed pattern noise (FPN) onto the image.
Most HSVC manufacturers provide some form of correction to
remove the FPN and the Olympus
i
-- SPEED LT,
i
-- SPEED 2
provides a fully automatic off--chip calibration system which
operates in under a second.
This system includes a mechanical shutter which removes the
requirement for the user to manually cover the lens as is found on
less capable cameras. The shutter gives a characteristic click
sound when it operates.
NOTE
When using the
i
-- SPEED 2 HG, the lens must be
completely covered (eg with a lens cap) from power on
until the splash screen appears.
The system operates automatically on start--up and also after a few
moments of operation and this should normally be sufficient. Under
extreme circumstances, however, especially in high temperature
environments, the calibration system may need to be manually
operated some time after switch--on. This is indicated by the
presence of FPN on the image. FPN will give the image a gritty
appearance, almost as though the picture has been printed onto
sandpaper, and may also produce thin vertical stripes.
The control to manually trigger the calibration is found in the menu
system.