Thanks for the reply;
I agree on the image size and don't know how much change there would be from the UV to IR, and should be correctable in software before merging. I am just thinking about things at this point. But for example, a single quartz objective would allow observing from UV out. Admittedly, the amount of UV is low, better at high altitudes, but might be possible, where normal glass absorbs a lot of what there would be. Certainly some UV work is possible as shown by Vensus filters. Also, quartz is better for work beyond 1100 nm, needs a different camera.

Finally, I just found out that the spectrohelioscope at Stellafane has an objective adjustment so other than H-alpha czn be observed.

Your image looks good, so obviously, narrow band alone is fine, and as you state certainly helps with the moon. I have a Stellena, which has a pollution filter built in, but the moon is still very problematic.

Thanks for responding and listening;
Jim

I have recently started to play with Narrow band imaging to see what it can show. In my latest attempt I imaged M20 (Messier object 20 the Trifid nebula) in Sagittarius. For this image I used 3 different 5 nanometer narrow band filters (Hydrogen Alpha (Ha), Oxygen 3 (OIII) and Sulfur 2 (SII) filters), to take 3 sets of images (one each filter).
The images where taken with an 11 megapixel Cooled CCD camera connected 16 inch Schmidt Cassegrain telescope at F10 (~4000mm focal length). Each set contained 16 images and each image was a 15 minute exposure for a total exposure time of 12 hours across the 3 sets. Each individual set was stacked together to improve the single to noise of each filter used. I also used Dark frames, Flat frames (different for each filter) and bias frames. To combine stacked images from each filter type into a full color image I used what is known as the Hubble Palette where SII is assigned to the red channel, Ha to the green channel and OIII to the blue channel. This creates a "False Color image", however the channels are picked this way to make it easier to see the composition of the nebula. On initial combination the nebula was very green and I had to greatly reduce the green to see the other colors come out, which is expected since the nebula is mainly hydrogen gas that was assigned to the green channel. The colors show some of the chemical composition of the nebula, the yellow through red show the ionized sulfur, the aqua through blue shows the ionized oxygen. Although I greatly reduce the green, the hydrogen signature still comes through as the orange to yellow color coming from the combination of the red from the sulfur mixed with the green from the hydrogen. Likewise the the aqua color being a combination of green and blue with the blue from the ionized oxygen and the green from the hydrogen. (Note: I'm using the color names in a loose fashion here as they are a bit arbitrary since the color assignment is not the real colors emitted by the elements in the nebula but only used to make easy to see the different components of the nebula). The first image is of the full nebula taken at a 4000mm focal length. The second image is a cropped version of the first image centered on what has been called the unicorn nebula inside the Trifid nebula. The second version has also been contrast enhanced to try and bring out more detail. For those interested last year I posted an image of the Trifid nebula taken with a DSLR at
https://www.uglyhedgehog.com/t-652657-1.html
The image taken with a DSLR is what the nebula would look like to our eyes if they where sensitive enough.

All questions comments and suggestions are welcome.

Correct on reflectors being better, corrector plate a problem and so are the additional optics as in Celestron HD models.

CCDs or CMOS good, not great, but can detect down to at least 350 nm, sensor data as listed generally not informative/shown below 400, I've asked astro camera makers and they generally know nothing more than graphs shown by sensor makers (often stop at 700 nm and SI based sensors good to 1100 nm). Bayer filters not good for UV, but not a total stoppage either, hot mirror on DSLRs bad news, but also not a total no go either (I've checked 60Da versus 60 full spectrum for UV photography of flowers, (not astro I know). Modern anti-reflection coatings on lenses worse than glass itself (Those on telescope optics should be fine), but again I've found modern Canon lenses to work for UV of flowers. Kolari has an article on 3 lenses tested for UV photography, found considerable theoritical differences (for UV work) between $600 and $65 (price I paid) lens, but no practical difference in photos. I found at work many things aren't as theory or older efforts have shown.

I have a totally mirror based scope and eventually I will see what can be done in the UV with a full spectrum Canon 60D.

For what it's worth, I believe efforts like yours using only narrow band filters are interesting and very worth exploring. If luminance is important, might try adding the narrow band filters together to create luminance values?

Good luck and thanks for making me consider things, may sound corny, but most valuable thing in the end to me;
Jim