THe Horsehead Nebula

[TrevorW]

The Horsehead Nebula - HaRGBL- 2h Ha-1h L and 1.5h each RGB- processed SIRIL and PS - when using the RGB Composition method in SIRIL after StarNet removed the stars it left behind red dots where the stars were on the image ???- so I processed L RGB and Ha separately applied star removal to each- then combined in PS using layers the resulting Tiff then converted to FIT, then star recomposition in SIRIL with no issues

[Startrek (Martin)]

Trev,


Nice Horsey to end or start the year


Some apparent background noise mottle there which could be due to SNR, calibration and stacking ?
Do you Dither each sub and use temperature matched Darks ?


Also big apparent halo around Alnitak , maybe your filters ?


Not and easy target all the same , most including me have trouble with Alnitak


Cheers
Martin

[TrevorW]

Hi Martin, the halo around Alnitak was more prominent in the blue stack than the other filters, not prevalent in Red and Ha. I don't dither, darks are temp matched, this was the last for Dec 2024