Planets

Images of planets are taken with the ZWO ASI 178MC. This is a fast video camera, which records sequences of images at a fast rate, with very short exposure times. Using AutoStackert, the sharpest frames of the videos are automatically selected and precisely stacked. This way, the so-called 'seeing' (wafting and wiggling of the image due to turbulence of the Earth's atmosphere) is largely removed. Using Registax, the final images are corrected for differential diffraction (in particular close to the horizon) and sharpened with a wavelet filter. This way, a video film of 2 to 3 minutes duration delivers sharp final images with effective exposure times of 3 to 10 seconds.
Jupiter on December 30, 2016 at 06:50 CEST.

Here we see a concrete example. A video film of planet Jupiter has been recorded using the ZWO ASI 178MC (download above), and a first image was obtained using AutoStackert (top left). This image was treated with a wavelet filter, resulting in the image shown in the bottom left. While the video clearly shows how the Earth's atmosphere distorts the image of Jupiter, the atmospheric structures of the planet are already rendered visible after stacking the best frames (30%). Treating this image with a wavelet filter yielded a final image in which a lot of structures show up, even though a telescope with a relatively short focal length was used for the observation. The movie was recorded for 1:19 minutes, with 19 frames/s and 50.46 ms exposure time each.

Jupiter on April 29, 2017 at 21:50 CEST.

Jupiter on October 9, 2021 at 21:34 CEST. Video recording with ZWO ASI 178 MC at 14" Skywatcher Dobson. Video length 180 s. 13341 frames, of which 15% were used. 74 frames/s with 1 ms exposure.

Saturn on August 1, 2018 at 22:54 CEST.
Saturn on July 29, 2018 at 23:15 CEST.
Mars on August 3, 2018 at 01:37 CEST.

Mars on November 5, 20:20 at 2041 CET. Video recording with ZWO ASI 178 MC at 14" Skywatcher Dobson. Video length 240 s. 16068 frames, of which 5% were used. 66 frames/s with 6 ms exposure.

Mars on July 30, 2018 at 01:37 CEST.