extronics iCAM501, Руководство по эксплуатации

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Operating Manual
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However, the reliability of the image analysis function is dependent on the nature of
the scene being photographed. Images which contain little or no details such as
edges (for example a blank wall) may be indicated as blurred when they are in-fact
acceptable. Therefore the user should bear this limitation in mind when taking
pictures, and it is suggested that users should take some practice shots to get a ‘feel’
for the way in which this software behaves.
Note that the iCAM501 has an anti-shake function. It takes four pictures and then
selects the best quality one to save to the flash memory. This is the reason that the
flash fires 4 times. This operates independently of the image blur analysis feature,
which examines the best of the 4 images taken.
2.8.4 Variable flash brightness
The December 2010 release of the iCAM501 firmware has an additional variable
flash brightness feature. The purpose of this feature is to reduce the incidence of
over-exposure of images when close-up shots of reflective surfaces are taken with
the flash.
When the flash is enabled, and a shot is triggered, a short low-brightness ‘ranging’
flash pulse will firstly be seen, immediately followed by the four flash pulses
previously described. The iCAM501 software rapidly analyses the reflected light level
from the ranging pulse, and adjusts the brightness of the flash accordingly. However,
this system is not infallible, and so the flash may still be too bright under some
circumstances. The camera will indicate a bad image if the light level is extremely
high, but if you are trying to photograph text close-up on a reflective rating plate for
example, it is strongly recommended to use ambient lighting where possible in such
applications.
2.8.5 Compatibility of the iCAM501 LED flash with optical flame detection
equipment
The flash LEDs fitted to the iCAM501 operate with a peak wavelength of 440nm (with
a secondary lower peak at 550nm).
Therefore the majority of the light emitted is
towards the blue end of the visible spectrum.
Typical UV/IR flame detectors operate in the 180-260nm UV range and the 2000-
4000nm IR range. Consequently the majority of the energy emitted by the flash on
the iCAM501 is well outside of the operating range of typical flame detectors.
However, Extronics have not done any testing of the iCAM501 with optical flame
detectors, so we cannot guarantee compatibility with any specific model of detector.
If you do find that particular sensors may be activated by the flash, it can be turned
off by the user with the press of a key as per the operating instructions in 2.8.1. In
addition, if you require the flash to be completely disabled for a particular camera,
Extronics can send you a field-installable software version which will disable the flash
(this of course can be reversed as desired by re-installing the normal software
version, again in the field).