Digital BW, The Print

>>The tests I've seen show that the 4990 is capable of resolving about 2100
ppi. So it would seem that scanning at anything higher is just increasing
the file size without gaining anything in useful information. I use a 4990
with 4x5 and 8x10 negatives.<<

That is about right.  You might want to do some shimming tests to see if you
can eek out a bit more sharpness.  Every bit helps with these scanners.
Norm Koren discusses this.  Here are two links that show examples:

http://www.normankoren.com/Tutorials/Epson_flatbeds.html#Focus_spacing

http://www.larry-bolch.com/ephemeral/4870-shims.htm

This example shows the difference when you hold the film really flat and
then adjust by only .2 mm (click on the image to enlarge it and see the text
in Internet Explorer):

http://farm3.static.flickr.com/2035/1664778870_ba674a82da_o.gif


Doug
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BetterScanning.com - Innovative Accessories for Better Film Scanning
http://www.BetterScanning.com/






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