it also doesnt correspond to the direction of tracking or polar alignment.
I get the same stars in a 2 minute exposure
but I took only 2.5 second exposures.
I turned off the tracking to compare direction of star movement. and its not the same direction. its off by like 10 degrees from where the stars are trailing.
To be honest the stars are trailing in an almost perfectly straight up and down motion in real life (The camera is slightly tilted so its at a slight angle)
My best guess is atmosphere/seeing possibly because I'm shooting somewhat low in the sky.
Actually on closer inspection I think it might be very slight sensor or focuser tilt. After stacking 320 frames to get a lower noise image. I can see very slight curvature in the bottom right corner of my image of the stars.
None in the other corners.
So possibly focuser tilt
AHHH! How do I fix the tilt without actual tilt adjustment screws? Theres no focuser tilt screws on my scope
SVbony sv503 70mm F6 ED telescope
With Orion Field Flattener for short refractors + a spacer to adjust the spacing.
canon SL1/100d
The bright star is arcturus
center then bottom right corner
Maybe this could be camera/shutter shake vibrations?
Or the mounts