ABSTRACT
The blurring effect of noise reduction potentially robs essential detail from an image. It is essential to ensure that either the tool itself or a protection mask directs the noise reduction to the lowest Signal to Noise Ratio (SNR) areas and equally does not soften star boundaries. Mure Denoise Script tool has evaded many for some time as it is hidden in the PixInsight script menu. It works exclusively on linear monochrome images corrupted by shot, dark current and read noise. Multiscale Linear Transform and Multiscale Median Transform are two multiscale tools that can sharpen and soften content at a specific image scale. The Starlet and Multiscale linear algorithms are different forms of multiscale analysis and are optimized for isolating and detecting structures. Both are isotropic, in that they modify the image exactly the same way in all directions, perfect for astrophotography. The degree of noise reduction is set by three parameters: threshold, amount and iterations.
