A great conjunction is the apparent closest approach of Jupiter and Saturn as Jupiter 'overtakes' Saturn in its orbit, an event that happens roughly every twenty years. The great conjunction of 2020 was distinguished by being the closest approach since 1623; they will pass very slightly closer in 2080. If this website is still up on 17 June 7541, then the amazing site of the two planets overlapping in the sky will be seen.
The picture below was taken on 20 December 2021, an unusually clear evening, as the following night, when closest approach happened, was forecast to be (and was) heavily clouded in the UK.
The equipment used was a Skywatcher 150PL telescope, HEQ5pro mount and a ZWO ASI1600 camera with ZWO RGB filters and electronic filter wheel.
This image of the moon was taken on the same evening, using the same equipment. For comparison the image of Jupiter and Saturn is a crop to about 10% the area of this image.: