ToupTek SkyEye45AC Plus Colour Cooled Camera

The ToupTek SkyEye45AC Plus is a cooled colour astronomy camera with Sony’s IMX366, a 44.7-megapixel full-frame sensor with 4.40 µm pixels. It sits between the 24AC Plus and 62AC Plus: more resolution than the first, and smaller files than the second, at about 90 MB per frame.

At 600 mm it samples at about 1.5″ per pixel. Read noise in low gain mode is 6.03–3.57 e⁻, higher than the other Plus cameras. In high gain mode it falls to 0.88 e⁻, so use high gain for faint targets.

This is the one SkyEye Plus without ToupTek’s zero amp-glow circuit. The glow is suppressed in hardware, and what remains comes out with dark frames, so take a dark library at your usual gain and temperature.

The full-frame sensor has a 43.1 mm diagonal. It needs a telescope, flattener or reducer that illuminates and corrects a field that size; otherwise the corners will show soft stars and vignetting. Two-stage cooling holds the sensor 35–40 °C below the air temperature.

Choose the window when you order. The IR-cut version is for normal colour imaging. Clear AR-coated glass lets infrared through, for use with your own filters in front of the camera, such as a dual-band or UV/IR-cut filter.

USB hub: one cable back to the computer

The back of the camera has a four-port USB 2.0 hub. The filter wheel, guide camera and focuser plug into it, so only one USB 3.0 cable runs back to the computer. A 512 MB buffer holds each frame while it transfers, so a slow USB link or a busy laptop doesn’t drop frames.

The camera runs from 12 V. USB doesn’t power it, and ToupTek recommends a 5 A supply when the hub is in use.

Dew, tilt and back focus

The sensor sits in a sealed, dry chamber, and the front window has a heater with four power settings. Three sets of push–pull screws in the body correct sensor tilt without a separate tilt plate.

Back focus is 17.5 mm from the M54 thread. The supplied 21 mm and 16.5 mm extenders bring it to the standard 55 mm used by most flatteners and reducers. Take the front adapter off and it drops to 12.5 mm, which helps when an off-axis guider and filter wheel have to fit in the same space.