Probably my short remarks are not helpful for anyone ... there are a number
of audiophiles on the list and I thought they would see similarities
removing sound distortions ... somewhat similar thought process as is done
digitally with images.
If you want to play ... http://www.deconvolve.net/ free software is
available. I haven't used it so can make no recommendations.
Jeff
On Thu, Feb 9, 2012 at 7:56 PM, <usher99@xxxxxxx> wrote:
> Blind deconvolution such as Lucy-Richardson (FM) seems to do quite a
> good job if over correction with "image ringing" and other artifacts
> are avoided despite total ignorance of the real PSF.
> I thought some of my earlier posts a few years ago may actually have
> resulted in capturing Moose's interest. As I understand it, most assume
> the Point Spread Function (PSF) is gaussian (that which blurred th
> image in the first place) and converge on the maximum likelihood
> estimation after an iterative process. (focus my Hubble, please)
> Linear motion is another possible PSF and I think will be correctable
> in the next PS CS version. DXO has attempted a light version of what
> Moose thought would be nice to do.
> Back 5 years ago or so the tech support at DXO was less guarded in what
> they would reveal. I very much doubt their lens specific profiles have
> true full wave solution PSFbut apply
> blind deconvolution in a weighted manner where the lens has the most
> need for it. Perhaps the "global slider" is a radius adjustment and the
> "detail" somewhat controls the iterations.
> (Just a guess) The focal distance specific correction of CA and
> geometric distortion included in the lens profile as well as the noise
> profiles are a plus. Too bad it doesn't quite
> live up to the concept but is worth using in some circumstances and
> exporting a tiff to PS.
>
>
> Keeping the convoluted in deconvolution, Mike
>
>
>
>
>
>
> Convolution ... Deconvolution would be changing between frequency and
> linear dimensions/ features. By measuring the frequency response of the
> system you can adjust/improve the output without being concerned with
> the
> individual parts of the system.
> Jeff
> On Feb 7, 2012 10:04 AM, "Moose" <olymoose@xxxxxxxxx> wrote:
>
> > On 2/7/2012 8:47 AM, Chris Barker wrote:
> > > Thanks for that appreciation, Moose, but what is deconvolution -- in
> > layman's terms? I've had a search on the Internet, but the
> explanations
> > mean nothing to me.
> >
> > Non-scientific, possibly/probably therefore not entirely accurate, but
> > indicative in a possibly useful way:
> >
> > When light is focused through a lens, the various imperfection in the
> lens
> > convolute it, "intricately fold, twist, or coil"
> >
> > If the characteristics of the lens and the focal and image distances
> are
> > mathematically defined, it is theoretically
> > possible to un-fold, un-spindle and un-mutilate the resultant image
> into
> > what it would have been if formed with a
> > perfect lens.
> >
> > In practical terms, the lens can't be perfectly known and described in
> > math, but the results of deconvolution may be
> > startlingly good.
> >
> > At the level I'm talking about, with Focus Magic and other consumer
> tools,
> > we have generic applications of deconvolution
> > that make lots of simplifying assumptions about the lens that may have
> > formed the image and allow specification of
> > simple input(s) and choice of input criteria based on viewing a small
> > sample of the image at 100%.
> >
> > Whilst far from the potential of custom tailored deconvolution, these
> > simple versions still accomplish semi-magical
> > transformations in many cases. FM, in this case, seems particularly
> suited
> > to images from the S100, for whatever reasons
> > of lens itself and sensor system. Oddly, this seems to be true across
> the
> > zoom range.
> >
> > Deconvolution is rather processor intensive. My speculation was that
> > someone, one of these days, will have an in-camera
> > processor with the power to do custom, in-camera deconvolution
> specific to
> > the lens, focal length and focal distance. I
> > suspect the results will be spectacular.
> >
> > In the meantime, I suspect that some enterprising geek will eventually
> > come up with a way to create lens profiles for
> > any lens and read focal distance from EXIF to make the corrections in
> a
> > post processing app.
> >
> > Looking at the corners of JPEG vs Raw files from the S100 in DPP,
> Canon's
> > own Raw converter, I see some quite amazing
> > corrections going on. Smeary, distorted stuff becomes clear. I don't
> think
> > is is deconvolution, in the full sense, but
> > I'm impressed. How do I work that into my work flow when corner
> details
> > matters to me?
> >
> > Convoluted Post Moose
>
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