This is integrated data I acquired a couple of years ago of the Witch Head Nebula with an Esprit 100ED and ASI 2600MC, markedly affected by linear artefact from the out of frame Rigel. I'm hoping to try again tonight (given the rare clear clear skies of the current La Nina). Does anyone have suggestions to reduce the linear artefact from Rigel?
You could get some black cardboard and cut out a ring that you tape to the end of your dewshield to make the scope stop down a bit to block the stray light.
