Eastern Veil. Again

[timh]

More on the Eastern veil this time using the Mosaic tools in PixInsight for a 2 panel matrix and incorporating narrow band.
Skywatcher S 200 Newtonian, Baader MkIII coma corrector F 5.0, Baader type II UV/IR filter, Ioptron CEM 70G mount , PHD2 guided using a f = 400mm 80 mm Achromat and ZWO ASI 120 MM camera. The imaging cameras were a ZWO ASI 1296 MC for RGB and a ZWO ASI 1296 MM for narrowband. Narrowband filters were an Optolong 6.5 nm S2, Optolong 7.0 nm HA and an Antlia 3 nm O3.

RGB OSC capture in Sharpcap 4.1 was ~ 150 x 40s frames at unity gain, dithered and pre-processed in PixInsight 1.9 to produce a CFA 1x drizzle integration for each of the two frames. HA and O3 captures of the two frames were each about 75 min comprising 3 min frames at gain 280 while the S2 captures were each about 2h.
For processing 4 separate mosaics , HA, O3 , S2 and OSC RGB were each compiled , sharpened and aligned. The RGB stars were extracted to be added back to the final images and -using Pixmath – the starless images processed as in the previous report to an RGB only image, an HOO + RGB image and a Hubble SHO image before the stars were added back to produce the 3 final images.
Aesthetically I find the HOO + RGB image most pleasing as a kind of enhanced semi-naturalistic image. The SHO is more informative though because it shows where the S2 is strongest (it more or less entirely overlaps the HA) at the -presumably- cooler more diffuse inside edge from which the thin shockwave has longer departed. It also shows a faint more mysterious HA edge apparently outside of the more recently shocked, hotter and more tightly focused threads of O3. Overall though it is fiendishly difficult to really understand what you are looking at within all the visual complexity.