This is a very modest example of three colur narrowband image. But I place it here, since it's my first one. At 11.09. I mainly shoot H-alpha, but before clouds rolled in I managed to capture 4 x 900s O-III and only single shot of S-II, 900s. I will shoot more O-III and S-III when ever weather allows me to do so. In this image the "Hubble paletete" is used where S-II = Red, H-alpha = Green and O-III = Blue

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NOTE
This image is taken by using QHY8 cooled 6.1mb color camera.
Its not an ideal tool for narrowband imaging.
Each color channel is shooted trough separate filter, this means,
that only 1/4 pixels are used for H-alpha and S-II.
O-III goes mainly to the Green and Blue
pixels of the Bayer matrix array, so about 3/4 of the pixels are used in this case.
How ever, very high quality narrowband images has been taken by using color cameras.