Dust problem: software solution?

[Weldon Thomson]

Obviously, the CCD clean would be the ideal solution but I'm curious, too, why software like digital ICE - which seems to work very well with my LS-2000 scanner - can't be employed, either in camera or in post processing, to eliminate dust spots. I'm guessing that it may be because dust spots on the CCD are not generally well defined with sharp edges - they are more often tiny blurry blobs?

 

[Jeff Blum]

I'm pretty sure Digital ICE uses an infrared hardware solution, not just software. Would be nice though - I didn't appreciate how much Digital ICE helped on my LS2000 until I scanned some B&W negatives and had to turn it off!

Jeff Blum, CEO
Glass Lantern, LLC
[email protected]
http://www.glasslantern.com

Obviously, the CCD clean would be the ideal solution but I'm
curious, too, why software like digital ICE - which seems to work
very well with my LS-2000 scanner - can't be employed, either in
camera or in post processing, to eliminate dust spots. I'm
guessing that it may be because dust spots on the CCD are not
generally well defined with sharp edges - they are more often tiny
blurry blobs?

 

[Holger Schulz]

A good idea, such a software. I often had the situation that only one or 2 larger dustspots were to be found on all images, sometimes hundreds, which I shot during one day. Such pieces of stubborn dust remain on the same location of the CCD for a long time. It would be great to have a tool to automatically remove such spots. I do a lot of panorama photography for printing. These panoramas are composed of 5 to 24 images, and on the final panorama you can see the dustspots repeating again and again, particularly in the sky. I normally remove these dust spots after the panorama has been created, but it would be much easier to batch remove the dust from the individual images before creating the panorama.

Good luck, I hope you will succeed.

Holger

Part of my job includes the development of image processing
software for medical applications. It seems to me that some of
the tools applied there would be adaptable to the CCD dust problem,
and I am thinking of writing a small piece of software that
addresses that problem (which will be freeware). The idea is the
following:

• At regular times, you have to shoot a "dust" image, e.g. small

aperture foto of a white wall out of focus

• From that "dust" image, the software can build a library of dust

spots

• The software can then apply that dust library to an actual

picture, replacing the dust pixels with the neighboring ones.
The last action can even be done in batch mode on a set of
images. The advantages would be much higher throughput (automatic)
and hopefully more reliable results.
However, I am not sure that the dust pattern is constant enough
over different exposures to make this method work (I guess one
dust image should be valid for at least 50 other ones).
So, this is my question: will this method work? If the answer
is positive, I will go ahead and write it (and share it). If not, I
don't
want to waiste my time.

--
Holger Schulz, wildlife tv
[email protected]