On May 9, 5:51 am, wrote:

That's a good thought, but I wouldn't know what values to put in the matrix. Reindeer does have the Richardson Lucy algorithm in their Fovea Pro package, but it costs more than Photoshop and would be overkill for most of us.

I note that the custom filter is a convolution filter, whereas RL is deconvolution. Perhaps one would put in the inverse of the convolution matrix?

Hi All,
A couple of notes about deconvolution. There is a distinction between deconvolution and blind deconvolution. For deconvolution, the blur function is in-hand, either by measuring it (e.g. taking an image of a single star) or modeling it using camera design (rarely ever done). When you use an filter, you can consider it as a very crude, but sometimes effective blind deconvolution.

The RL method is a deconvolution method that calls for having a blur function, also called a point spread function (PSF). Some people have made modifications to the approach such that it operates on a wider range of images, creating a Blind RL method. However, it is not the only approach. Maximum entropy methods are also effective and prevalent. Now, I am biased on this last point, but for convenience, speed, and effectiveness, its tough to top the results provided by SeDDaRA. Descriptions of blind deconvolution methods can be found at http://quarktet.com/BlindDecon.html, while many examples start at http://quarktet.com/Gallery1.html.

One caveat though, with any of these methods, the PSF must be preserved in the image for the techniques to work. If this information is lost due to noise or digital truncation, the restoration will not be very effective.

Jim at Quarktet

JimAtQuarktet

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