Новости от
www.qhyccd.comQHYCCD News letter April 2015
1. software update
QHY8
ASCOM Plugins V33 released
renovate：Close cooling function is invalid.
addition：Automatic uninstall function（This function is not applicable to the
previous version, still need to manually uninstall the version installed before)
QHY9
ASCOM Plugins V203 released
renovate：Close cooling function is invalid.
QHY21
ASCOM Plugins V3.5 released
renovate：Close cooling function is invalid.
addition：Automatic uninstall function（This function is not applicable to the p
revious version, still need to manually uninstall the version installed before
QHY22
ASCOM V3.5 released
renovate：Close cooling function is invalid.
addition：Automatic uninstall function（This function is not applicable to the
previous version, still need to manually uninstall the version installed before)
QHY23
ASCOM Plugins V2. released
renovate：Close cooling function is invalid.
QHY11
ASCOM Plugins V3.5 released
renovate：Cooling off function is invalid.
addition：Automatic uninstall function（This function is not applicable to the p
revious version, still need to manually uninstall the version installed before)
EZCAP
Version（3.3.4） released
renovate：Fit Header page information not write to Fit the image file problem
(only save in the Capture mode Fit image will write the information）
2. We send some pictures of these cameras to you:
QHY5L-II QHY8L/10/12 QHY9 QHY11 miniCAM5S
3. miniCAM5S Dark field test photos FIT, and Readout noise index.
Please check the test photos from here
http://www.qhyccd.com/minicam5/MINICAM5-Thermal-NOISE-GAIN0.zipPlease check the Readout noise index from here
http://qhyccd.com/ccdbbs/index.php?topic=4951.04. miniCAM5S Precautions for use
a. According to the test results of readout noise , when gain: 0 , electronics:7 ,
when gain : 1 - 3 , electronic:4 , when gain: 4, electronics:2.6.So usually, we
suggest to set the gain : 1 or 2. When capture the weak target,during the filming,
need a large number of superposition in a short time, set the gain:4.
Gain: 4 readout noise is minimal，but FULL WELL also minimal. It saturated easily
with a bit bright.Therefore only suitable the situation for each exposure time is
short, then a large number of superposition. Because the readout noise is low，in
the process of the superposition will not bring in additional noise.So the effect of
100 pictures in 10 seconds and 1 picture in 1000seconds are basic the same.
b. Even have adopted double refrigerating unit, the best it can do is reducing
to environment temperature to- 45 degrees, but we do not suggest too lon
g exposure time. But recommend the way that shorter each exposure time wi
th a large number of superposition method. This has several advantages: one
is to reduce the risks of long exposure, such as the tracking error, bad USB
transmission frame. And the thermal noise level is low, easy to be calibrated.
If the exposure time is very long, can cause some pixels of thermal noise lev
el is high, sometimes dark field is difficult to calibrate. In general, for novices,
we suggest that the single exposure time shorter than 2 minutes. Those who
good at photography and masters of post-processing, of course, they can co
ntrol exposure time more long.
c. Because the camera inside the large capacity of the frame buffer is not us
ed, there is only 4 k USB buffer. When the CPU is busy, can't read in time,
will exist the possibility of bad frames. For continuous video image, the occas
ional lost one image is not obvious, it does not affect the shooting. And if t
he exposure time is longer, is easy to see. QHYCCD to identify bad frames in
the software, and made a special mark on the bad image. After been shot,
use a software was carried out on the folder image scanning, will automatical
ly remove bad frames, so that the bad frame will not be superimposed to th
e image.
d. The correction of FPN noise. Every time start the software, or after the rec
onnect the camera, or modify the gain, the CMOS chip will FPN correction cir
cuit of CMOS FPN noise correction at a time. Rectification is completed, will
no longer be automatic correction. The FPN noise is related to temperature. I
f CMOS temperature change, the FPN noise will change. So after the tempera
ture stability of the temperature control, need making FPN modification once
again. Correction is located in one of the advanced Settings button. After re
ctification is completed, will find that there is still a very weak residual FPN. I
t can be removed by doing dark field. But the dark field must be the same t
emperature.
It is important to notice that every time after shoting the dark field needs to be
done. Because every time after FPN noise correction, the residual noise is different.
So need to do the dark field calibration to adjust the noise each time.
5. Temperature control using PID algorithm, at the request of users, in order to
avoid the refrigerating unit and CCD thermal shock, intentionally reduce the
velocity of temperature control, so the temperature will slowly down to the target
temperature.
6. Attention to the problem of grounding. If use the battery, the problem is
not big. If use a 12V ac adapter, need to make sure that the 12V and comp
uter are on the same ground. Please check
http://qhyccd.com/en/top/faq/generic-faq/
