Hi Seb,
PlateSolving is usually very reliable in Telescopius but, for some reason, this wide field image is failing to solve: https://telescopius.com/pictures/view/115419/deep_sky/markarian-chain/markarian-s-chain/by-nico1038
Image center RA: 12 29 02.755 Dec: +12 56 58.70
Field of view 10d 17’ 23.0" x 6d 52’ 37.7"
Resolution 3.980 arcsec/px
Nico