Hi @agriggio Adding a dark frame to an image gave me a weird result. Anyone else seen this? Without: With: The ISO doesn’t match exactly (400 on scene, 100 on dark frame) but still unexpected Files here: R5BT6282.CR3 (33.6 MB) R5BT6282.CR3.arp (11.6 KB) R5BT100ISO10s.CR3 (17.9 MB) Th…