[casstony]

The filters work fine with any size refractor in my experience, including the 60mm that I used to have.
Here's a couple of my shots with the L-extreme under 80 to 90% moonlight through the 150ED at f/6.
M17 was 56 minutes last night, very close to the moon.
The Helix was 5 hours.
I guess they'd be noticeably better without the moon but clear nights have been rare for the past few months.