Here are more tests with this lens, but this time I used my NIKON D7000. After these images I found out that the field flattener is in a wrong position.
Image taken in bright moonlight. There is nothing special to be expected besides M109 galaxy to be on this image.
03 March 2023 - 1833UT - ISO2000 - 62*20s - NIKON D7000 - Nighthawk with FPL53 lens 80/480mm and field flattener.
Single image of the series with a satellite flashing through.
03 March 2023 - 1845UT - ISO2000 - 1*20s - NIKON D7000 - Nighthawk with FPL53 lens 80/480mm and field flattener.
Here is a good image of the Moon. No more colour fringes.
03 March 2023 - 2043UT - ISO400 - 1/500s - NIKON D7000 - Nighthawk with FPL53 lens 80/480mm and field flattener.
This image taken with the Lumix G110 little earlier shows a weird behaviour of this camera. Have this (see markings) blurrish with other lenses as well. Have no hint, what it is.
03 March 2023 - 1710UT - ISO400 - 1/800s - LUMIX G110 - Nighthawk with FPL53 lens 80/480mm and field flattener.
Optics : StellarVue Nighthawk Modified Refractor d=80mm f=480mm (f=1/6) : Intes MK-67 Maksutov Type Reflector d=150mm f=1800mm (f=1/12) Camera : NIKON D7000 DSLR unmodified (from 2011) : Panasonic LUMIX G110 MFT System (from 2021) : The Imaging Source DMK21AU4.AS monochrome USB highspeed camera Filter : IR/UV Cut, Astronomik H-Alpha, Astronomik LRGB 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 with MT1(RA) & MT1(DEC) Controller : Littlefoot Controller (selfmade) Guiding : PHD Aquisition : DELL Notebook (Windows 10) Image Processing : ImagesPlus, NeatImage 7, Registax 6, DeepSkyStacker, Gimp latest list update : March 2023