The ASI533MC Pro features Sony's latest back-illuminated CMOS IMX533 sensor. Its 1-inch, square, 9.07 MP sensor is ideal for astrophotography and can be considered an iteration of the venerable ASI183MC Pro.
This latest generation camera retains key features of the ASI183 series--such as an attractive QE figure and high frame rate--but now includes zero amp glow, extreme low readout noise (as low as 1.0e), 3.76 microns pixel size and an improved 2 stage TEC cooler.
Below you'll see an incredible image of the Rosette Nebula taken by Jason Guenzel using the Triad Ultra on the super-fast f/2.2 Celestron RASA telescope and using the ZWO ASI533 Camera!
The Sony IMX533 Sensor
The IMX533 is a 1-inch, 9 MP CMOS image sensor in a square format with a 3.76 um pixel size, capable of producing frames at 20 frames/sec in 14-bit mode. Its readout noise is as low as 1.0e which makes it comparable to SCMOS or EMCCD sensors and highly suitable for high-definition, low-noise imaging.
Back-Illuminated Sensor Design
Sony's back-illuminated CMOS image sensor improves sensitivity and noise reduction - the key factors to enhancing image quality, while radically realigning their fundamental pixel structure from front-illumination to back-illumination. It has retained the advantages of CMOS image sensors such as low power consumption and high-speed operation.
With a conventional front-illumination structure, the metal wiring and transistors on the surface of the silicon substrate that form the sensor's light-sensitive area (photo-diode) impede photon gathering carried out by the on-chip lens. A back-illuminated structure minimizes the degradation of sensitivity to optical angle response, while also increasing the amount of light that enters each pixel due to the lack of obstacles such as metal wiring and transistors that have been moved to the reverse of the silicon substrate.
Sony developed a unique photo-diode structure and on-chip lens optimized for back-illuminated structures, that achieve higher sensitivity and a lower random noise without light by reducing noise, dark current, and defect pixels compared to the conventional front-illuminated structure.
Low readout noise, high dynamic range.
Quantum Efficiency Curve
ZWO estimates the QE peak value is more than 80%. - (Graph from initial testing).
Zero Amp Glow
Traditional CMOS sensors produce a weak infrared light source during operation quite often seen in the corner of uncalibrated images as the tell-tale signs of amp glow. As the ASI533MC PRO uses zero amp glow circuitry, you won’t have to worry about amp glow even when using high gain, long exposure imaging.
Camera with amp glow – exposure 300-second exposure:
ASI553 frame with no amp glow – Exposure 300 seconds:
DDR Memory Buffer
The ASI533MC PRO is equipped with a USB 3.0 interface, and even in 14-bit mode, can reach 20 frames per second. The 256 MB DDR3 memory ensures stable downloading of frames with increased USB speeds.
ASI533MC Pro vs. ASI183MC Pro Comparison
ZWO-AC-DC12V5A = American Standard.