A week ago or so I finally got my new highspeed camera QHY5III715C, a CMOS camera capable of pushing 250 colour frames of 600*600 pixels (1,45 Ám size) per second in 8-bit mode and still impressive 45 full frame 8,2MP in 16-bit mode.

After weeks of rain and with Saturn coming close to opposition I made my first ever try with the camera on my MAK 150/1800mm. Those tiny pixels should good enough for that I had not to use eyepiece projection for that focal lenght of 1800 mm.

But with Saturn being at low declination it will not go high over the houses. I took some videos of 1000 images each, but Saturn kept jumping through the whole frame od 640*480 pixels. The image below is the only "good" one; the first of Saturn after many years.

While setting up for imaging I found out that there is some severe periodic error of 2 minutes on my GP mount. The 2nd image from 4 August 2023 clearly shows this periodic error. The reason seems to be in a not well centred wheel in the RA step motor.

Wobbling Saturn
04 August 2023 - 2122UT - 1000 frames (10s) - QHY5III715C - Intes MK67 Maksutov 150/1800mm

Test image for periodic error
04 August 2023 - 2122UT - 300s - QHY5III715C - Intes MK67 Maksutov 150/1800mm


Optics              : Omegon Pro AP Triplet ED FCD-100 d=85 f=510mm Apochromat (f=1/6)
                    : Intes MK-67 Maksutov Type Reflector d=150mm f=1800mm (f=1/12)
Camera              : Omegon veTec 533 C Colour CMOS Camera with IMX533 square 9MP sensor 3,75Ám pixels
                    : QHY 5III715C Colour CMOS IMX715 8,2MP sensor 1,45Ám pixels high speed
                    : NIKON D7000 DSLR unmodified (from 2011)
                    : The Imaging Source DMK21AU4.AS monochrome USB highspeed camera
                    : Panasonic LUMIX G110 MFT System (from 2021)
Filter              : IR/UV Cut, Astronomik H-Alpha, Astronomik LRGB set + folter drawer
add. optics         : ED 2x Barlow lens, eyepiece projection
                    : 35mm, 50mm, 135mm and 200mm NIKON lenses available
                    : 2.8/60mm Sigma, 12 .. 60mm Leica for MFT system
Mount               : VIXEN GP Highspeed Step Motors
Controller          : EQStar Pro (since May 2023)
Guiding             : PHD2
Aquisition          : DELL Notebook (Windows 10), SharpCap, FireCapture and others
Image Processing    : DeepSkyStacker, Siril, Gimp and others

latest list update  : August 2023