I'm in the process of making a 2 panel mosaic between the Horsehead and the Orion nebulae.
As you may already know M42 is really bright and requires HDR imaging. By searching online I've come up to this workflow in PixInsight:
- WBPP registering the reference frame by panel (2+x stacks total: 2 normal exposures, x short exposures)
- Gradient removal (ABE, DBE, Graxpert...) on each stack
- BXT correct only on each stack
- SPCC on each stack
- HDRComposition on the M42 panel
- MosaicByCoordinates
- PhotometricMosaic
- BXT with non-stellar sharpening on the mosaic
- Normal linear processing
- Stretch
- HDRMultiscaleTransform on the non-linear image
- Normal non-linear processing
Does this make sense or is it wrong in any step?