From: Jim Chung <jim_chung@sunshine.net>

Date: December 24, 2009 3:08:23 PM MST

To: Astro_IIDC@yahoogroups.com

Subject: Re: [Astro_IIDC] Re: Sunspots!

Hey Tim,

I dissected a PST and removed its tiny 20mm diameter etalon and stuck it behind my 105mm AP Traveler wearing an 80 mm energy rejection filter (ERF).  The placement of the etalon is critical, it has to operate in a f/10 environment and be placed about 20 cm in front of the focal point.  The advantage to all this is for a budget price you basically have a 80mm diameter Ha solar scope and enhanced resolution.

You can see a photo of it from an earlier post on this forum about 2 weeks ago.

Jim