Eye Opener II

On several occasions when using the SCT visually, I noticed a significant glare around bright objects (e.g. planets). This is caused by internal reflections in the optical system. I also ran into this problem during imaging several time. For example the January 21 raw frames of M109 are completely ruined by the reflections of the light of a nearby star.
I found that the standard visual back of the SCT is a major cause of this. Flocking it is however not an option as this increases vignetting. To test this theory, I took some flats on December 26, 2003. Indeed, with the standard visual back my replacement f/3.3 focal reducer has an ADU drop of 7% across the field when used with the ST-7XE camera. But, after flocking the inside of this original visual back, this increased to 12%.
I figured that although an Eye Opener II would theoretically not have any benefits with my 1.25 inch eye pieces, nor with my cameras, it may actually lead to a reduction of the reflections. So I bought one, and found that it was actually even more reflective than the original visual back. Indeed, it is slightly worse than the original visual back in regard to the glare.
However, after flocking the inside of the Eye Opener II, it is actually much better than the original visual back. When using the camera with the f/3.3 focal reducer flocking the Eye Opener II doesn't have any negative effects (the 7% ADU drop remains). However, the glare is very significantly reduced when using it visually with bright objects.

So, for my purposes the Eye Opener II isn't beneficial because it reduces vignetting, but it is only because I have more room to add some flocking to suppress the reflections.