Thanks much for the info, Mike. I will probably be getting the
Semi-APO.

- Bruce


--- In Baader-Planetarium@yahoogroups.com, "Mike Swanson"
<swanson.michael@...> wrote:
>
> Hi Bruce,
>
> I actually have all three of these filters - I got them years apart as
they were introduced, first the MSG, then the Fringe-Killer, then the
Semi-APO. The Semi-APO is almost always mounted in the front of the
diagonal in my 102SLT to reduce chromatic aberration (which it does
quite well). The Fringe-Killer had that role prior to the Semi-APO
coming along. Now I mainly only use it when imaging with my NexImage
camera (web cam) due to its infrared, UV and violet cutoff features. The
MSG gets used the least - mainly just to enhance contrast and detail on
Jupiter and then in my NexStar 11 GPS. The sky glow reduction of the MSG
is subtle, especially in a smaller scope like the 102SLT. The main
advantage in your case would be the more natural color the sky glow
filtering effect imparts when coupled with the minus-violet. That same
effect occurs with the MSG and Fringe-Killer stacked or with the
Semi-APO alone.
>
> Hope that helps and gives you an idea of some of the options.
>
> Best regards,
> Mike Swanson
> Author of "The NexStar User's Guide"
> Author of "NexStar Observer List"
> http://www.NexStarSite.com
>
>
>
> --- In Baader-Planetarium@yahoogroups.com, "Bruce Huston" hustonbj@
wrote:
> >
> > I have a Celestron NexStar 102SLT (4 inch f/6.5 achromatic). I am
considering getting the Baader Fringe Killer filter to get rid of
chromatic aberration. Since almost all my viewing is in suburban
locations with lots of sky glow, I am considering the Moon and Sky Glow
filter as well. Here is my question: what would be the
advantages/disadvantages of getting these two filters, versus getting
the Semi-APO? I realize that the Semi-APO would be slightly cheaper, but
are there other factors I should consider. Any suggestions would be very
much appriciated.
> >
>