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Ha = Red, [NII] = Green, [NII] = Blue
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Hydrogen Alpha only
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[Nitrogen II] only
The color image and two component images above split the Ha and [NII] lines using very narrow band filters. The Ha emission line is located at 656.3nm and the [NII] line is located at 658.3nm. In a wider filter, the Ha and [NII] lines would both be passed. Filters such as the Schuler Ha or the Astronomik Ha will not separate the Ha from the [NII] lines. The 3nm FWHM Custom Scientific filters can separate the two lines as this image reveals.
Taken December 26, 2003 from my backyard in Castro Valley, Ca.
C14 imaging scope @4430mm focal length (f/12.46) stabilized with mirror locks and with camera angle adjuster
FLI IMG1024S imaging camera @ -40C
SBIG AO7 Adaptive Optics System
SBIG ST7E Guide/AO control camera @-20C
RCOS Dichroic Beam Splitter for AO7/IMG compatibility
FLI CFW 1 filter wheel
Custom Scientific Narrowband Emission Line Filter
Hydrogen alpha 656.3nm 3nm FWHM
[Nitrogen II] 658.3nm 3nm FWHM
Exposure details:
3 exposures of 45 minutes for [NII], Halpha
Maxim DL used for IMG1024S control
CCDSOFT 5.00.71 used for AO7/ST7E control
Sigma prebeta 11 used for darks, flats, biases and light combine
Photoshop CS used for final touch up
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