ToupTek ATR533M Mono Cooled Camera

The ToupTek ATR533M is a cooled mono astronomy camera with Sony’s IMX533, a 1″ square sensor of 9 megapixels with 3.76 µm pixels. Peak quantum efficiency is above 90%, and there’s no amp glow.

It’s a sensible first mono camera for narrowband and LRGB. 1.25″ filters cover the 16 mm diagonal, so the filter wheel and filters cost less than for larger sensors. At 800 mm it samples at about 0.97″ per pixel; at 400 mm, about 1.9″. In low noise mode read noise drops to 0.27 e⁻, and a high full well mode doubles capacity to about 105 ke⁻.

Cooling, dew and power

Two-stage cooling takes the sensor up to 42 °C below the air temperature. It holds the set point to within 0.1 °C, so dark frames can be reused from night to night. A heater on the front window has four power settings and can be switched off in software. Cooling needs 12 V; the 12 V 3 A power supply is in the box.

Back focus and connections

Back focus is 17.5 mm from the M42 thread. Adapter rings and extension tubes are included to build out to the spacing your flattener or reducer needs, usually 55 mm. A USB 2.0 hub on the back takes a filter wheel or guide camera, so fewer cables run down the mount. A 512 MB buffer holds each frame while it transfers, so a slow USB link doesn’t drop frames.