QHY21 QHY22 and QHY23 camera is using the sony's lastest high sensitivity ExviewII CCD sensor ICX674,ICX694 and ICX814. These sensors has very high QE(close to 80%) and very low thermal noise. With QHYCCD's dual stage TEC cooling technology these camera will get great -45C temperature below ambient. To compare with the competitor, this temperature gives -10 to -15C extra cooling and it will give you very clear background even in a hot summer.
The readout noise of QHY21,22,23 is also a highlight. It is typical 5 electrons. The readout noise is very important when you capture the faint deep sky object or using the narrow banding filter. Less readout noise means you can get better image when you stacking the same pictures. In another word, you can get same quality with less pictures.
QHY21,22,23 has a solid design. It comes with a USB/Power cable fixer. With this fixer the USB and power cable will never get off from camera and they will get constant electrical contact.