QHYCCD QHY5III485C USB 3.0 Camera
Large Sensor Size
High QE and sHCG
While the QHY5III485C does not have the extended near IR response of the QHY5III462C it does have sHGC (Super High Cain Conversion for exceptionally low (less than 1e-) read noise. For solar and lunar imaging, the NIR response is not required but the ability to take multiple short exposures in H-alpha light is ideal for solar use and making movies of solar prominences, arcs and eruptions.
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.