Re: COOLSCAN II backend

Rogier Wolff (R.E.Wolff@BitWizard.nl)
Wed, 6 Aug 1997 22:39:38 +0200 (MET DST)

Michael K. Johnson wrote:
>
>
> Didier Carlier writes:
> >The umax backend seems ok, with little modifications, I got it to do
> >simple things like the INQUIRE and POSITION commands on the COOLSCAN,
> >and these seem to work. It even reads data but unfortunately the
> >picture I get is a 28.8 Meg file all black ;-).
>
> Ooh, that means you really are most of the way there. I'm fairly
> certain that the problem is that the scanner is confused by the
> set window command -- that often causes scanners to return all
> zeros for data. Of course, getting the rest of the way there
> can be a long journey. I don't know what you have done so far,
> but I'd try reducing the size of the window descriptor block,
> probably to just the minimum defined by section 14 of the scsi
> 2 standard. That gives less potential for conflict between
> elements in the wdb, and a better chance of a good scan. If
> that works, you can fill the wdb back in once you hear from Nikon
> what their vendor-specific extensions to the wdb look like.

Ohhh.. The coolscan wdb looks pretty normal.

Didier do you have the SCSI spec? So does "section 14" mean anything
to you?

Anyway, the Windows driver issues a "change units" command, and then
programs the window in pixels. The scan range is about an inch, so it
sets the units to 1/2800th of an inch or something close to that.

You can also try to simply specify a window of 0, 0 to 0.5, 0.5
(600,600 in the default resolution of 1/1200th of an inch).

Michael, your scanner just gives "black" when you give it a bad window?
The Tamarack simply locks up :-( ...

Roger.

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