Re: ATM Double image

["Betsy or Mike Marchand" <bmarchan@mnsi.net>]

>My 10" dob has recently
>acquired the ability to produce double images, just very slightly
>offset

fwiw, I've seen similar effect from eyepieces that have been dis-assembled
and then re-assembled without concentricity of lenses being maintained (they
slop to one side of their cell a bit). Can give an astigmatic appearance
which is discerned by rotating the eyepiece in the focuser to determine if
it is the offending element.

Or perhaps internal reflections
between your barlow and eyepiece might be creeping into the scenario too.
Again rotate in the focuser to check...

- mike