Digital BW, The Print

Godfrey - 

I have heard that in the sub-$1000 range, the CCD devices in scanners 
are pretty much the same. According to this notion, a key factor is 
the quality of the optics. 

Might that explain why my Epson 1640 output, at 1600 dpi, resembles 
my Minolta at 800 dpi ? 

In other words, my Epson delivers the promised 1600 dots, but the 
dots represent a smoewhat blurry image. By this reckoning, Epson 
isn't really guilty of overstating anything. The dots are there. 

Looking over the promotional material for the Microtek 2500 scanner, 
I see that it uses two lenses: one for 2500 dpi scanning over a small 
area, the other for 1250 dpi scanning over the entire bed.

... does this seem reasonable ?

> You're just relying upon the driver's ability to subsample the 
scanner
> output. I've seen differences in quality even between driver 
versions in
> that case. 
> 
> Best test would be to use a calibration test target with LP/MM 
markings,
> scan at max optical resolution on the Epson (and the Minolta), and 
then
> just examine the scan to see what the actual best case resolution 
is. I
> have been intending to get one for focus calibration work just 
haven't had
> the time. 
>