button to begin the process. A status bar will appear to let you know the progress. Five iterations on a small image should take only a few seconds.
When it finishes, you will be left with a new image that looks a bit sharper than the original. With only five iterations, the results are slightly less sharp than the unsharp masked version we created earlier. Run an unsharp mask on the original image to compare the two.
Try running the deconvolution on the original image with more iterations but the same other parameters. For a start, try 32 iterations. The image initially becomes sharper with more iterations. However, at some point—typically several hundred iterations—increasing the number will produce no further improvement.
Step 4: Try a Deep-Sky Object. Load the image "NGC6888.fts" from the Image Enhancement tutorial subdirectory. This is an image of the Crescent Nebula imaged through a Hydrogen-alpha filter by one of the authors. We will use L-R deconvolution to sharpen up the star images. Invoke the Deconvolution Tool (it helps to move it off to the left side of the screen) and set it up as follows:
Point Spread Function: Gaussian PSF based on selected stars
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