Horsehead IC 5070
Pelican Nebula

(Click on image for Full Resolution H-Alpha)

(Move your mouse over image to see the L=Ha+R,R=Ha+R,GB color image
using Robert Gendler's Photoshop technique)

(Click Here for Full Resolution Color)

(Click Here for an Ha processing comparison using "OZONE" plugin for Photoshop)

Date: August 20-23, 2003
Exposure: Ha (3nm) 240 min : 12 x 1200s
RGB : 20:20:32   10 - 120s R, G and 8 - 240s B
Processing: MaxIm Ver 3.2 for Image calibration, 20 flats , dark subtracted and Sigma Reject combined, 30 bias frames Sigma Reject combined, 16-1200s darks Sigma Reject combined, alignment, normalization. Photoshop for final balance and jpg conversion.
Conditions: Poor, Mag 1-2 Skies 100% humidity and heavy haze
Scope: AP155EDF, f/7 (1.59 arcsec/pixel)
Camera: SBIG ST-8E/CFW-8, -20° Water cooling used to reach temp
Comments: I took 2 hours the first night thinking that might be enough. After processing, the noise was still too significant, so I added another two hours the next night. Conditions we consistantly poor for all 4 hours of exposure. However, the additional time did improve the S/N in the image and it processed out much smoother. The RGB data was originally taken with 10 min exposures, but the blooming on the bright stars was too much to process out. I went back the next night and took 2 min and 4 min exposures and this helped control the blooming.