Re: Calibration problem on UMAX Astra 1220S

Oliver Rauch (oliver.rauch@Wolfsburg.DE)
Tue, 23 Mar 1999 13:08:48 +0100

Dean Martin Townsley wrote:

> Hi all,
> My problem with the calibration is simple: I can't get it to perform the
> calibration. I'm using sane 1.00 with the build-1 patch for the umax drivers
> and xsane 0.18 for the frontend (tried xscanimage too).
> I stuck a debug message in the code to supplement the messages already
> there and found that dev->do_calibration was zero when the scan process went
> through the do_calibration() function even when the box for "Quality
> Calibration" was checked in the interface. The code checks and to me seems
> to only perform the calibration if this is nonzero. I don't know if this is
> a problem in the driver itself or somewhere else but both xsane and
> xscanimage exhibit the same problem. That's as far as I got, I have final
> exams for the next two days (take homes) so I won't be able to fiddle again
> until after that probably, but I figured I'd say something so someone with
> better knowledge of the code can maybe investigate.
>
> oh, btw, /proc/scsi/scsi says
> Host: scsi0 Channel: 00 Id: 05 Lun: 00
> Vendor: UMAX Model: Astra 1220S Rev: V1.1
> Type: Scanner ANSI SCSI revision: 02
>
> Which I presume means it's firmware 1.1, (out of a possible 1.5, ugh).
>

Hi Dean,

like described in the sane-umax-docs the quality calibration does not work with
all scanners!

What happens or does not happen if you enable quality calibration?

Background:
There are some problems with calibration by driver. UMAX uses a different
kind of calibration for each scanner model and firmware. I only know the one of
the Umax Supervista S12 with firmware 2.0.

If you set the quality calibration button, the driver requests a quality
calibration
from the scanner. If the scanner is not able to do the quality calibration on
its own,
it requests the driver to do this. In that case do_calibration is set in the
driver.
Then the scanner sends the calibration data, the driver does the calibration and

sends back the calibration data.

If the scanner does not request that the driver has to do the calibration, there
is
nothing what the driver can do.

Bye
Oliver

--
EMAIL: Oliver.Rauch@Wolfsburg.DE
WWW: http://www.wolfsburg.de/~rauch

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