QHYCCD QHY12 User Manual
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When exposure time is relative short (for high-
speed downloads, the exposure time is less than 2
seconds, for the low-speed download, exposure
time is less than 9 seconds) QHY10/12
automatically select two-frame exposure mode,
that is, exposed twice, and the twice exposures use
the same time. After the first exposure will readout
the first data, after the second exposure will
readout the second data read. This realize the
same exposure time for all pixels The mode of
double frame exposure will need double exposure
time. So when exposure time is longer, QHY10/12
will select automatically single frame exposure
mode, that is, exposed only once. Meanwhile
special hardware inside the camera will spend the
same time for the first exposure and the second
exposure
Please note: if the shooting scene changes during
the exposure, the image of double frame exposure
may not same. So QHY10/12 is not suitable for
rapidly changing objects or fast moving objects.
If you have to do like that, you can install
mechanical shutter of QHYCCD. Please contact
your area dealer or QHYCCD to consult about the
supply of mechanical shutter
About controlling for BLOOMING
QHY10/12 CCD chip have the -100dB ainti-
overflow foundation. Anti-overflow capacity is
slightly lower than QHY8PRO of-110dB. So there is
possible to overflow for shooting very bright target
For the overflow problem of SONY CCD chip,
please install mechanical shutter to solve. If
mechanical shutter is indeed necessary, please
consult QHYCCD or your area dealer.
Protection of Cooler
The double cooler of QHY10/12 can reach to 40-45
Centi
degrees difference in environmental
temperature. So need to avoid thermal shock.
Thermal shock means internal stress of cooler
happen to change due to expansion or contraction
caused by the rapid changes in temperature of
cooler. Strong thermal shock will shorten use age
of cooler or even irreparable defect of cooler.
The method of avoiding thermal shock is this: To
avoid reaching maximum power of cooler when
booting machine. Ensure to increase gradually
power of cooler. When stopping machine work ,
after reduce gradually power of cooler shutdown
and turn off the power of machine.