Actually scanning the same image twice is not exactly the same as multipass
scanning in Vuescan - I wish Ed were here to answer this, but I recall a
post he made where he described using the "course" positioning stepper to
position to the frame and the a "fine" stepper to scan/multi-scan.
So, If you actually scan twice the course stepper must be used to position
twice which is not as accurate.
[mailto:firstname.lastname@example.org]On Behalf Of Herm
Sent: Monday, July 09, 2001 3:49 PM
Subject: Re: filmscanners: Silverfast and LS1000
the way to test is to scan the same image twice, then subtract them from
other in photoshop.. if you get all black then its ok, usually you will see
few defects. I will include an example so you can see it. I inverted the
so you could see the differences.
"Frank Nichols" <frank@theNichols.net> wrote:
>I am very picky - I checked several times at 1200% magnification and I saw
>no vertical or horizontal offsets visible at the pixel level. The reason I
>said "appears" is that I assume there is some slack or play in the
>mechanism and perfect can not be achivied.
>The reason I was skeptical was I tried using multipass scanning on a
>(HP5370) and saw the offset effect. Since the offset was repeatable I
>suggested to ED H (Vuescan) that he include an option to allow the user to
>input an offset value for subsequent passes.