Telescope:

8" f5 Newtonian reflector

Camera:

 ST-8XME, self-guided, binned 1x1, temp -20c, camera control MaxIm DL 4.56

Image:

Red (Hoya 25A) filter, 240 minutes (24 x 10 minute subs), 12/14/2006

Processing:

 CCDStack 1.1, Photoshop 7.0

Location:

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

Notes:

This image replaces the unfiltered 60 minute Track & Accumulate image from November 2005.

According to "Star Clusters", by Brent Archinal and Steven Hynes, the size of this open cluster is 15 arc minutes.

From the NGC / IC Project:

Contemporary Visual Observation(s) for NGC 2099

NGC 2099 = M37 = Cr 75
05 52 19 +32 33.2
V = 5.6;  Size 24

8": very large, very rich cluster, over 150 stars, rich in mag 10-13 stars.  A 
red star is near the center.  Best of the three bright Messier open clusters in 
Auriga and one of the top open clusters in the sky.

- by Steve Gottlieb