My PixInsight tutorial for applying noise reduction techniques to images, both monochrome and colour. This tutorial covers the main processes – MultiscaleLinearTransform (replacement for ATrousWaveletTransform), MultiscaleMedianTransform, ACDNR and TGVDenoise. Detailed examples are provided with advice for optimal use.
Source: Light Vortex Astronomy: TUTORIAL (PixInsight): Noise Reduction