Stray light on right edge of images of M51 Whirlpool Galaxy, only with Ha & S ZWO 7nm narrowband filters.
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I'm very new to astrophotography, I've been imaging my first galaxy, M51 Whirlpool Galaxy, over the last 2 weeks on the rare clear nights we get in Illinois. Only when imaging with Ha & I believe it was also with the S filter (if not S, then OIII). They're ZWO filters & they are installed properly. There is no stray light outside getting into the telescope & I don't believe that it is being caused by a nearby star bleeding light into the image, I've checked for that as well.
It's a William Optics Pleiades 111 with ZWO ASI183MM camera, ZWO CCA (camera rotator) & ZWO Electronic Filter Wheel, the backspace is at 55mm as far as I'm aware. I thought that perhaps the filter was in backwards, but it won't work if screwed in from the back, as the wheel cannot rotate then. I'm at a loss & it's going to negatively affect my images. Could it be amp glow from the camera being reflected in a weird way? I don't get the stray light when using any other filters.
Does anyone have any idea what it could be? I've checked everything I can think of. I would greatly appreciate any assistance, as I'm at a loss here & don't have a clue what is causing it.
Something else I just thought to mention, the stray light stays on the right side of the images no matter how the camera is rotated.