2-panel top/bottom before/after image.
Top: original image. Bottom: 'Color Taming' parameter used. Note the stars now appear less conspicuous as their colours blend in with the rest of the object.

Two 'Mode' settings are available;

  • 'Tighten' has the effect of tightening a stars around their central core.
  • 'Dim' has the effect of dimming stars luminosity.

The Shrink module uses an iterative process; the strength of the Tighten or Dim effect is controlled by the number of 'Iterations', as well as the 'Regularization' parameter that dampens the effect. The stringing and pitting artefacts commonly produced by less sophisticated techniques, is thereby avoided.

An image with stringing and pitting artefacts.
The Shrink module's iterative algorithm avoids these sort of stringing and pitting artefacts typically produced by unsophisticated morphological transformations.

The 'Color Taming' parameter forces stars to progressively adopt the colouring of their surroundings, like "chameleons".

The 'Halo Extend' parameter effectively grows the given mask temporarily, thereby including more of each star's surroundings.

If the image has been deconvolved or sharpened and the stars may be subject to subtle ringing artefacts, then the 'De-ringing' parameter will take this into account when shrinking the stellar profiles, as to not exacerbate the ringing.

The 'Un-glow' feature attempts to reduce the halos around bright, over-exposing stars. 'Un-glow Strength' throttles the strength of the effect. The 'Un-glow Kernel' specifies the width of the halos.