Originally posted by GUB It is their presence that makes me look to the sensor area for this issue.
The sensor cover glass and AA crystals and UV/IR are all planar surfaces: you're barking up the wrong tree.
Originally posted by GUB The image of the newton rings is well defined and about as sharp as actual photographs of them normally are.
The geometric structure of the rings is a good indicator of their origins in a photographic optical system. They will appear regardless of F-stop because it is a very destructive interference pattern.
If the optical interference patterns were occurring between planar surfaces such as the AA UV/IR stack they would look like this:
Instead we are getting concentric rings that look like this:
(Image deliberately enhanced to show rings)
Which indicates a spherical surface impacting on a plane in the optical path. By definition, lenses have curved surfaces - filters are flat, this combination is all that is needed to cause newton rings.
Originally posted by GUB It is possible the monochrome green of the aurora is a factor
The monochromatic nature of light from the aurora is certainly a factor in heightening the intensity of the newton rings. Under white light, they are prismatic - colours are split according to frequency, but under monochromatic light they take on alternating light/dark patterns.
The theory that the spectrum selective lens coatings are destructively interacting, or amplifying the effect with the monochromatic light is an interesting hypothesis. But i'm skeptical as the coatings on the lenses we use are very broad, and have multiple thicknesses and the surfaces they are applied to have differing geometry* which makes the propagation of optical interference patterns, especially destructive ones at selective light frequencies: to be highly unlikely.
*such as Aspheric elements.