Hi all, I'm having a bit of an issue understanding what maybe wrong with the results i'm getting. The 0.7x reducer is set at 146mm from the end of its rear thread to the camera chip (zwo 1600 pro). But when I plate solve the image its the same field of view as at native F11. Surely even if my back focus was wrong I should see some reduction in F/L
This is a plate solve of one sub with the 0.7x reducer fitted, it's binned 2x2 but unless i've calculated it wrong it's still near the F11 native 3900mm focal length?
This is at F11 3900mm
my imaging train
I can't possibly be so far off with my back focus measurements so I would appreciate any ideas you have.
cheers
ceefna