One tidbit that I don't think has been stated: each 0.3 OD equals 1 stop (2X
the light. Log 2=0.3) So, all else being equal, a scanner with a 3.6 OD
range could distinguish 2 more stops detail than one rated at 3.0 by the
same standards. In practice, all else is seldom equal, and the specs are not
standardized. The only instance that I would put any stock in comparing
these numbers would be 2 scanners from the same manufacturer. An example is
Polaroid, who to their credit is conservative in their ratings, rating the
SS4000 at 3.4 and the SS120 at 3.9. I'm afraid that marketing pressure must
have prevailed with the newly-announced SS4000 Plus. It's rated at 4.2 (to
counter Nikon and Minolta) which is clearly just the theoretical A/D range
for a 14-bit system.
Lloyd
----- Original Message -----
From: "Ken Durling" <kdurling@earthlink.net>
To: <filmscanners@halftone.co.uk>
Sent: Wednesday, October 31, 2001 11:09 AM
Subject: filmscanners: Re: Dynamic range
> What is the dynamic range figure - i.e.3.2, 3.4 or whatever - a
> measurement of? Or maybe I should ask, what is the unit of
> measurement?
>
>
> Ken Durling
>
>
>
> Photo.net portfolio:
>
>
>
>
