This is the North America Nebula (NGC 7000) and the Pelican Nebula (IC 5070) in the same frame. If you saw my previous post, I did this object with the Baader Neodymium (Moon & Skyglow) Filter and this image was done with the IDAS Nebula Booster NBZ Filter. As I stated last time, the filters are quite different in what they are designed for and the light they filter. The Baader Skyglow is a broadband filter which allows for most light to pass through but certain wavelengths commonly associated with streetlights are blocked. The IDAS NBZ is a dual narrowband filter that only allows for certain wavelengths (~500nm & 656nm) which correspond to Oxygen III (495.9nm & 500.7nm) and Hydrogen Alpha (656.3nm).
As expected, this version looks quite different from the Baader image. The overall color from the image using the NBZ filter is heavier in red which is due to its high abundance of hydrogen and the lighter colors scattered throughout are due to the oxygen. In addition to showing more of the nebulosity, the finer detail is much more apparent. This image shows fine strands and puffy clouds which are not always visible in the other image.
To process this image I separated the stacked image into red, green, and blue channels. The reason for this is because I wanted to create hydrogen (Ha) and oxygen (OIII) images out of the RGB. Since the hydrogen wavelength is in the red spectrum, the red band was used for Ha. The OIII wavelength is a little tricky as it mostly resides in the green-blue spectrum so I made the oxygen from a blend of 70% green and 30% blue - this combination is used because the oxygen band is mostly in the green band. I then combined the Ha in the red band and OIII in the green and blue bands making it an HOO image. The advantage is it gets rid of some unwanted noise and brings out a bit more detail.
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