Latest M33 Image - Galaxy in Triangulum

Image Details:

M33 Half-resolution uncropped after color balancing
Half Res M33
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 M33 Full Resolution M33 Full Res cropped with better color balance
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See this link for my previous images of M33 from my backyard under really bad sky conditions.
 Telescope Takahashi FS-128 at F/8
 Mount Astrophysics 1200 Goto
 Camera Class 1 NABG ST-8E, CFW8 (old filters). All images were taken at -18C without using the second cooling stage.
Camera Control Software MaximDL/CCD 2.02 Beta
 Location Semi-dark site, Pacheco Pass Park, 40 miles from San Jose, California.
 Date October 8, 1999
 Sky Conditions Very good transparency, excellent seeing, low to moderate humidity.
 Exposures R=10 min (2x5 min)
G=10 min (2x5 min)
B=10 min (2x5 min)
Lum=85 min (17x5 min with IR filter on)
 Image Resolution RGB: 2x2 binned (765x510)
Luminance: unbinned (1530x1020)
 Processing All frames were corrected with bias and dark frames. Flat fielding was unnecessary from this site (no light polution and stray light to get in the optical path.)

MaximDL was used to acquire and calibrate the individual images with bias, dark, and flat field frames. MIRA AP 6 was used to register the monochrome images. Since the red, green, and blue components were 2x2 binned I resized the image to match up with the luminance layer's dimensions. I did this with Photoshop 5.5 using the bicubic algorithm to interpolate the data.

I then imported the image back into MaximDL and used the "Split Tricolor" command to get back the R, G, and B components. Then I opened the Luminance component (on which I used DDP at about the 60% setting to bring out core details) and recombined using the LRGB option in the Combine Color dialog.

Since I did equal interval RGB exposures I had to weight the green slightly (1.10x) and the blue a little more (1.35x). Interestingly, these ratios are a lot less than what is normally recommended but the nebulae and stars looked the right color. Perhaps the "Equalize Background" option, which I had checked, had something to do with this.

Lastly, I used Photoshop's rubber stamping tool to fix the blooming spike on the bright left-hand star and to clean up various bright and dark pixels on the image.