Apache-Talk @lexa.ru 

Inet-Admins @info.east.ru 

Filmscanners @halftone.co.uk 

Security-alerts @yandex-team.ru 

nginx-ru @sysoev.ru 




      :: Filmscanners
Filmscanners mailing list archive (filmscanners@halftone.co.uk)

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: filmscanners: Was New Nikon performance, now dust

At 02:56 AM 6/11/01 EDT, Ed Hamrick wrote:

>Unsharp masking isn't a reasonable way to compare the scans, since
>this doesn't get to the root of why there's a difference between the
>results from the two scanners.

I disagree here, Ed.  Here's why.

It seems some scanner vendors (maybe all) implement internal 
trade-offs between noise and resolution.

Sharpness and resolution can't be considered separately from 
noise, since the are inter-related.

I did a round of tests on my Epson 1640SU (a flatbed touted 
by Epson as a film scanner also) and was thoroughly convinced 
that Epson's 1600 dpi claim was a sham.

However... with enough USM, the Epson's output can be shown to 
contain much more detail than you might think.  With the extra 
detail comes lots of noise, of course.

I'm guessing that Epson traded off resolution for lower noise 
in this model.  PS: the results of these tests (and scans from 
several medium-format film scanners) may be seen at:


You can see for yourself what I'm talking about -- download one 
of the JPGs from the 1640, and apply USM in Photoshop.  The 
results may surprise you.

rafe b.


Copyright © Lexa Software, 1996-2009.