Since the first days that I started making astrophotography, one of my goals was to get to elaborate images in Hubble palette, a very beautiful and fascinating color composition that has also a scientific purpose. For this reason, in mid-June of this year I decided to buy a SII (Ionized Sulfur) filter to try to do some narrow band imaging with my color OSC, already having a dual-band filter available from which to extract the signals of ionized Hydrogen and Oxygen, completing everything with a broadband filter to take the color of the stars.
The Hubble palette is a processing technique devised by NASA technicians to highlight the three most important gases that make up the emission nebulae, namely Sulfur (chemical symbol S), Hydrogen (H) and Oxygen (O) . This is possible by arbitrarily assigning the Sulfur signal to the red channel (R), the Hydrogen signal to the green channel (G) and the Oxygen signal to the blue channel (B), obtaining a false color RGB image that is indicated with the initials SHO, by the chemical symbols of ionized gases.

In the composition you see here, I wanted to compare the classic bicolor HOO palette, which is generally done with color cameras, with the SHO palette of 12 very different nebulae, both in chemical composition and in surface brightness. The image contains everything I managed to do from home in 4 months by pointing my 2 telescopes (Konus 200/1000 and SW Evostar 80ED) towards some nebulae in North/North-East direction, located in the constellations of Cepheus, Cassiopeia, Perseus and Auriga and taking advantage of every little flash of clear sky. In total, I managed to acquire a total of 265h and 49min of integration time with the L_eXtreme (recently replaced by L_Ultimate), SII and UV / IR-cut filters.
I had a lot of fun collecting so many shots (also helped a lot by the weather) and I hope I was even a little bit of inspirational for those who, like me, cannot afford (economically or for lack of time) to have a monochrome camera with filters and filter wheel but at the same time wanting to make narrow band imaging.