Garfield, I would go back to the original screen shots and reprocess them - rather than trying to fix a flaw that some previous processing introduced.
If the Intelihance step introduces problems - perhaps it is not the best 'correction' step?
A screen shot should not have dust or other such noise in it - and I can't think why an 'Intelihance' filtering would make the image appear to have dust spots. Do you mean it has enhanced these small flaws?
You have mentioned some of the actions that are available here for download so it sounds like you have found the '
RP Goodies' - have a look at the 'SmartDuster' and the 'AutoScanSpotting' actions, but any automated approach is often a compromise, unless the image is really bad to start with.
For many images - you can run these spotting actions and then use a layer mask to only apply these corrections to areas that do not have great detail, such as backgrounds. Important foreground subjects of interest are masked and a new layer is added for manual clone stamp use for these more critical areas. This way the automation can help with the less critical tedius areas and the critical image detail is hand worked.
Usually the clone stamp tool or the healing brush tool might be used for most common spotting of random stray spots. If you have sections that have concentrations of many more spots which are harder to remove, make a rough shaped (not marquee) feathered selection that includes the damaged area and apply the dust/scratch filter. Start with the minimum settings and gradually increase until you are happy with the effect of the dust removal - this is often a trade off on image quality vs spot removal.
In many cases a small setting will remove dust and not damage fine detail - but may soften texture...this is no problem, after filtering the dust run the add noise filter with small amounts of monochromatic or coloured noise. I like to mix both types of noise patterns using smaller settings instead of a larger noise of a single type. It is also good to add just a little too much noise and to then use the fade command to reduce the effect - you can also change the fade blend to dissolve which adds a random noise type pattern to the fade too!
Although the D/S filter can be applied to a large pixel area - it works best when the selection area is more specific to the problem area. This way it can combine the good pixels into the bad without altering too many of the good pixels. The problem is that it can be hard for computers to know what is 'good' or 'bad' - this is why a small selection of the area of concern is needed.
As to your question about my 'ReduceUSM' action - USM stands for Unsharp Mask, or the most commonly used sharpening method. This action was not designed to work with dust spots, but to help rescue an image that has been oversharpened without keeping a backup before sharpening or for any time when you need to soften the 'edges' of an image. The DigiDeluxe and other smart noise removal actions usually try to preserve edge and fine detail while smoothing flat areas, since this is the most common type of edit. One would hope that no one would ever need to use the ReduceUSM action - as this is a last resort approach.
On a related side note on some recent software mentioned here for correction of defects...The new beta plugs for the Alien Skin Image Doctor seem promising - but I have not found the Polaroid PC app to be that useful.
Hope this helps,
Stephen Marsh.