Getting Halos, suggestions please?

[MartyS]

Am using the LS 4000ED and SF 5.5.2r20 Ai.

When I scan a transparency image that is contrasty (bright subject against a dark background) I sometimes get a persistent "halo" surrounding the bright subject. It's an agrivating problem that I've tried to solve.

Sometimes the only way I can reduce the glow is to darken the background selectively within levels, curves or selective color.

To rid the glow satisfactorily usually requires some careful selections and manipulations within them.

Any suggestions to eliminate these halos or how to deal with them?????

Thank you

Marty

[Tomaz Klinc]

Dust is collecting on the two mirrors, lens, CCD inside your scanner. You have two options: (i) send the scanner in for servicing; (ii) do the cleanup yourself---but don't do it if unexperienced with fine instruments.
The thorough cleanup requires disassembling of almost the whole scanner, a pro job, but for a quick fix try this: have on hand a can of air, some isopropyl alcohol, cotton swabs; unplug the scanner, unscrew (2 screws on the back) and remove the scanner's cover; locate the two mirrors, one on top, the other deeper down a well, not very accessible, but still; blow the mirrors with compressed air; moisten the swabs with alcohol and wipe the mirrors thoroughly but very, very gently--be careful not to scratch or disturb them; blow them again with air; replace cover. If you're lucky, you'll be back in business; if the problem persists, send the scanner for servicing (to reach lens, CCD, the thing has to be taken apart---not to be attempted by a fainthearted photog).