[AstroRudi]

Hi,

this is a very interesting question ! I am doing astronomy since 35 years and I recently bought a (rather famous) 5 mm eyepeice and I had (for the first time in my life) an effect similar to the one you describe: when looking after bright objects, the background around the object is not black, but takes over a reflection from the bright object and makes the background of (nearly) the whole filed of view "shining".

I tried a lot of thing to avoid this effect of "shining" (I blackened the edges of the eyepiece lenses with a black text marker etc), but it did not have any effect. I believe the thing is called "scattering" or "ghosting", but I have no idea from what it comes in the case of my eyepiece.

I am wondering whether the eyepiece producer is testing new glass sorts !

Clear skies

Rudi