Joe S. wrote:
I may have too many eyepieces for my XT-12, 1500mm focal length, f4.9.

Included in my eyepieces are a 10mm Radian and a 5mm Nagler Type 6, and, a
TV 2X Barlow.

Do I need the 5mm, or, will the 10mm with Barlow provide the same results?
Views through the 5mm are really crisp and bright -- will I lose anything
with the Barlow?


Why not do an A:B comparison of the two arrangements? It may depend on
the scope to some extent, since at f/4.9 it is pretty fast. Plus the
Radian and Naglers have other differering characteristics.

If the Nagler is surplus, you can likely get a good price for it at
Astromart :-)

Phil