Am I the only one who thinks the $40 DSLR clip in filter beat my $300 light pollution filter on the Orion Nebula?
Shot the same 8 minute stacks from my driveway in Boise and the cheap clip in version kept way more star color and fine detail than the fancy screw on one, so what am I actually paying extra for?
Clip in filters sit way closer to the sensor than screw on ones, so the light hits them at a tighter angle. That alone cuts down on the color shift and scattered light you get with a filter hanging out at the end of the lens. Your $300 one might just be built for a different setup than your camera.