On Sat, 30 Oct 2004 17:26:24 -0500, "Tetractys"
wrote:

BTW, what do you use to clean the glass?
I use lens cleaner and lens paper but this
still seems to leave a thin film/smudges behind
no matter how thorough I am. I even tried to
polish this off using a microfiber cloth but just
can't seem to get it all off. I'm starting
to get the feeling I'm just redistributing it.

Windex with ammonia works pretty well.
Lenscrafters sells an alcohol-based glasses
cleaner that works also. To wipe, I use
lint-free lab wipes. You're quite right, though;
that last bit of residue is really tough, and it
takes multiple passes with solvents. I use lots
of liquid and big wipes.

I was afraid to use household cleaners because I wasn't sure what
effect that will have on the glass. I mean, for all I know, there may
be some special coating that might be affected by the chemicals.

But if this is indeed regular glass (although made with better
tolerances, of course) I'll give it a squirt of Windex and see how it
goes.

BTW, I'm probably overdoing it anyway because the smudges are very
faint. In order to even see them I have to look at the glass almost
parallel to the scanner (looking from above, I don't see any smudges).

A good test is to do a scan with the lid open in a darkened room
(nothing on the glass). This will show all the dust/smudges, etc.
However, to actually see them, the image must be brightened radically.
And I mean radically! Since that amount of extreme brightening will
never be needed for real images, these last few imperfections will be
drowned by image data and virtually invisible.

Don.