Combining images from 3 telescopes

I have combined three images together taken using three different telescopes: A ten inch reflector, A 4 inch refactor and a 3 inch refractor.
Notice how deep the image is. This images were captured using a full set of Astronomick RGB and narrowband filters. The sub-frames ranged from one minute , five minutes and ten minutes, with matching dark frames and flat field frames. The total exposure time was 24 hours and 40 minutes.

3 scopes narrowband luminance, RGB colour

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3 scopes narrowband

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Full size