SW PDS200 Newtonian Image using a combination of ASI294 MC and ASI294MM cameras obtained by combining broad band OSC RGB and Mono camera BLUE filter integrations with narrow band SII, HA and OIII integrations.  The additional blue filter information was used to improve the representation of the pulsar synchrotron light in the final image.  The red channel was built by adding the HA, SII and the red channel from the RGB integration in proportion according to their estimated SNRs relative to just the M1 part of the image.  Similarly the green channel combined the OIII with the green channel from the RGB and the Blue channel combined  the BLUE filter, blue channel from RGB and OIII contributions.  The three channels were calibrated and combined in pixmath to produce a naturalistic RGB image - but enhanced in detail via the NB contributions.

Although much of the light coming from M1 is narrowband - with the NB filters embracing at least most of it in the form of HA, NII, OIII and SII - perhaps the most interesting feature of M1 is the pulsar at the core. Only 10 km or so across and yet so hot and bright that it is clearly visible even at some 5000 light years distant - rotating at relativistic speeds which separate out charges  within the neutron star to generate powerful rotating magnetic fields that  trap charged particles and generate a continuous spectrum of synchrotron electromagnetic radiation. Within the visible spectrum this can be detected as bluish light from the UV up to about 500nm.  An An interesting sidelight on this is that the synchrotron light is fading quite quickly. The status of M1 as M1 may reflect the fact that it was significantly brighter in the 18'th century ?  The following paper is a good read on the topic where the rate of fade is measured as the apparent increase in OIII linewidth as the baseline (synchrotron radiation) continues to fade. https://academic.oup.com/mnras/article/346/3/885/982620.