Hi Mike,

Check out this image of M27 in Ha. Ten hour exposure ... very
impressive. Here's the details:

"I shot this image of M27 over the past few nights through Ha, [OIII]
and a Blue filter.
I had 5.75 hours of Ha, 3.25 hours of [OIII] and one hour of Blue.
The emission line exposures were 15 minutes and were exposed through
Custom Scientific 3nm FWHM emission line filters.
The camera is a Finger Lakes IMG1024S "Dream Machine" which uses a
Tektronix TK1024 sensor.
An SBIG AO7 was used along with an SBIG ST7E and an RCOS Optical Systems
Dichroic Beam Splitter to guide and AO-correct the FLI camera.
The imaging scope is a Celestron C14 operating at f./11 (3910mm Focal
Length) mounted on an Astro-Physics AP1200GTO mount."

http://www.rdcrisp.darkhorizons.org/...hao3b_page.htm

Tris