Doug please take a look at the attached image. This the view down through the front of an AOX/FW8G. As you can see, part of the filters either side of the filter in front of the sensor is visible. I am seeing artefacts in my images that are not showing in my flats; this is something that is on going with my other thread. I can see well defined arc shaped shadows in the top left and lower right of my images...and I am now seeing this on a second STXL11002/FW8G/AOX system on a different scope. Is it possible that while the AOX is operating at or near its extremities that it is bouncing light reflecting off those nearby filters. Martin
The AO-X doesn't tilt a huge amount - nowhere near as far off-axis as that photo was taken. I really don't see how it would cause problems with adjacent filters that are outside the light path. If you are concerned about stray light you could add a baffle that reduces the front aperture. As a test you could cut a ring of cardboard and clamp it between the nosepiece and the front of the AO. Just make sure the aperture is large enough to clear the guide camera pickoff mirror.