Telescope:

 8" f5 Newtonian reflector

Camera:

 ST-8XME, self-guided, binned 1x1, temp -25c, camera control MaxIm DL 4.56

Image:

Lumicon Red filter, 780 minutes (78 x 10 minute subs), 12/26/27/28/2008; seeing 2.3-3.9 FWHM per CCDStack

Processing:

CCDStack 1.4.1, Photoshop 7.0

Location:

 Rolling Roof Observatory, Thousand Oaks, CA 91360 (+34d 13m 29s -118h 52m 20s)

Notes:

This image replaces an unfiltered 200 minute sequence from 01/24/2006.

According to "Star Clusters", by Brent Archinal and Steven Hynes, the size of the open cluster NGC 1893 is 25 arc minutes.