This very nearly true color RGB type image reveals the Crab Nebula without the inner synchrotron radiation illuminated core region seen in conventional images. Here we see only the red hydrogen filaments defining the explosive event seen by the Chinese in 1054 AD. The filaments can be seen to be moving outward over periods of dozens of years, in photos such as this one. A more standard RGB image can be seen here. And I also have a tri color polarized image here.

Processing: There is no masking, hole cutting, or pasting to make this rather straight forward image. It is a simple HaGB image, composed of a red channel in Ha light, and a standard green and blue filter for the G and B. This technique is commonly used by tri-color tech pan film photographers to enhance nebula in wide field shots, and retain approximately correct colors. An example is using a Wratten 92 for Red, 58 for green and 47 for blue in tri-color images with schmidt cameras. Exposure ratios are selected to give a white color balance with a G2V star. Calibration, and RGB compositing of the images was done in Maxim DL.

Instrument:  12.5" f/5 Home made Newtonian
Platform:  Astrophysics 1200 QMD
CCD Camera:  SBIG ST8i
Exposure:  HaGB = 120:10:10
RGB Combine Ratio:  1: .5: .5
Filters:  GB Tricolor + Custom Scientific 3nm Ha
Location:  Payson, Arizona
Elevation:  5150 ft.
Sky:  Seeing FMHW = 2.2 arcsec, Transparency 6/10
Outside Temperature:  5 C
CCD Temperature:  -20 C
Processing:  Maxim DL, Photoshop.

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