ZWO ASI533MM [MONO]

The ZWO ASI 533MM is a monochrome un-cooled camera for planetary imaging and EAA and features a 9MP back-illuminated CMOS sensor with 91% quantum efficiency at 460nm.

The ZWO ASI 553MM contains the Sony IMX533 CMOS monochrome sensor which has a diagonal of 15.99mm and a resolution of 9 MP. The Sony STARVIS back-illuminated sensor technology is highly sensitive and has exceptionally low read noise.

ZWO cameras incorporate a 256MB DDR3 memory buffer that improves data transfer reliability and it minimizes amp-glow caused by slow data transfer speeds.

A higher QE means more of the light is converted into signal. The ASI 533MM has a maximum QE of 91%.

Traditional CMOS sensors emit a weak infrared light and quite often it is seen in the corner of uncalibrated images. This is called "amp glow". The ASI533MM uses a zero amp glow circuitry which eliminates the problem, even when using high gain and a long exposure.

With amp glow – exposure of 300 seconds:

ASI553 frame with no amp glow – exposure of 300 seconds: