Περιγραφή
QHY410C uses Sony’s latest back-illuminated, full
frame color sensor. The IMX410 is equipped with the sensor that used in
the Nikon Z6, and Sony A7III. In addition to BSI, the IMX410 also has
larger 5.94 um pixels giving it increases sensitivity of extended
objects in low light. The IMX410 is expected to be Sony’s most sensitive
full frame color sensor for astrophotography.
QHY410C has 1GB DDRIII buffer to cache the image and avoid the risk
of a frame loss. This avoids problems of a busy USB port when there are
other peripherals using the same port as the camera.
BSI
One benefit of the back-illuminated CMOS
structure is improved full well capacity. In a typical front-illuminated
sensor, photons from the target entering the photosensitive layer of
the sensor must first pass through the metal wiring that is embedded
just above the photosensitive layer. The wiring structure reflects some
of the photons and reduces the efficiency of the sensor.
In the back- illuminated sensor the light
is allowed to enter the photosensitive surface from the reverse side. In
this case the sensor’s embedded wiring structure is below the
photosensitive layer. As a result, more incoming photons strike the
photosensitive layer and more electrons are generated and captured in
the pixel well. This ratio of photon to electron production is called
quantum efficiency. The higher the quantum efficiency the more efficient
the sensor is at converting photons to electrons and hence the more
sensitive the sensor is to capturing an image of something dim.
TRUE RAW Data
In the DSLR implementation there is a RAW
image output, but typically it is not completely RAW. Some evidence of
noise reduction and hot pixel removal is still visible on close
inspection. This can have a negative effect on the image for astronomy
such as the “star eater” effect. However, QHY Cameras offer TRUE RAW
IMAGE OUTPUT and produces an image comprised of the original signal
only, thereby maintaining the maximum flexibility for post-acquisition
astronomical image processing programs and other scientific imaging
applications.
Anti-Dew Technology
Based on almost 20-year cooled camera
design experience, The QHY cooled camera has implemented the fully dew
control solutions. The optic window has built-in dew heater and the
chamber is protected from internal humidity condensation. An electric
heating board for the chamber window can prevent the formation of dew
and the sensor itself is kept dry with our silicon gel tube socket
design for control of humidity within the sensor chamber.
Cooling
In addition to dual stage TE cooling, QHYCCD implements proprietary technology in hardware to control the dark current noise.
