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Use Linked Wavelet Layers (1)
This is a complete new way to use wavelets.  The inventors are Jean-Jacques Poupeau and  Elie Rousset who independently came up with this idea several years ago. Last autumn Sylvain Weiller told me about this idea and we have now added this as a new processing part of RegiStax.

Normally the stacked image is "divided" over the wavelet-layers based on the gaussian sharpen filter. When Linked Wavelet Layer is used the stacked image is divided over the sucessive layers based on the denoise and sharpen filters and the setting of the slider. This creates a complete different way to sharpen the images. In this example below we will show/explain one of the ways to use this new tool.

The source for the images below was kindly provided by Bob Pilz, processing was done by Cor Berrevoets.

Figure 1: the result after stacking 300 frames, the startingpoint for wavelet enhancement


Figure 2: We have increased the sharpness/details simply by setting slider 1 to a higher value.


Figure 3: We keep the same setting for slider 1 but now also checkmark Linked Wavelets. Notice the difference between this figure and figure 2, the overall sharpness and the level of the details (craterlets inside Plato) is a lot better.


Figure 4: Now we increase slider 2, this not only enhances  details but cleary enhances the noise a lot too. This is typical for Linked Wavelets, we will need to use a denoising filter to limit the noise.
 

Figure 5: Most of the noise will probably originate in layer 1, so we start by activating a denoise filter in layer1 which clearly helps a lot.


Figure 6: But Denoising layer 1 isnt enough so we also denoise layer 2 and make additional  changes in the sharpen-filters to get a reasonable balance between detail and noise.