Re: Microtek Phantom 636cx again

Bernd Schroeder (bernd@aquila.muc.de)
Sat, 16 Oct 1999 18:51:38 +0200

Hi,

sorry for the late response.

On Tue, Oct 05, 1999 at 08:13:20PM +0200, =??Q?Nov=E1k_Levente?= wrote:
>
>
> On Tue, 05 Oct 1999 19:14:20 Bernd Schroeder wrote:
> > Hi,
> >
> > On Tue, Oct 05, 1999 at 09:30:55AM +0200, Levente NOVAK wrote:
>
> > > - the image mirrored (like if it would be seen through a mirror)
> > > - vertical stripes or bands, especially one much darker. It is like if the
> > > scanned image would be a copy produced by a dirty copier or a printer
> > > which has toner problems.
> > > None of the above problems is present when I scan under Windows. The
> > > mirror phenomenon is not really annoying as I can flip the images with an
> > > appropriate program, but the dark stripe is. Does the scanner compensate
> > > under Windows for the fluorescent tube's light unevenness, or is it
> > > something else?
> >
> > If I knew, what the scan software does under Windows, it would probably be
> > easier to fix problem of a certain type. But normally there is a colour
> > calibration process at the beginning of each scani which does exactly
> > such a compensation. According to the
> > spec this calibration can either be performed by the device or by the
> > backend. Default is that the device does the calibration, so one could
> > try the calibration by backend, but this is where the other phantom cx models
> > stopped working, and it won't work for your particular device anyways.
>
> Unfortunately I don't know of a method what would permit to "intercept" the commands sent by the Windows driver. Do you?
>

You could try it with wine, which has builtin tracing capabilities.
I tried it some months ago with a SCSI model and managed to get it
scanning the SCSI bus using the ASPI 16-bit layer with a simple
test application, that comes with the Microtek software. IIRC it is
called scantest.exe.

>
> > > Advanced picture system: No
> > > Stripes: No
> > > Slides: Yes
> >
> > This is the reason why the backend aborted, when you first tried it.
> > Normally the TMA and ADF option can be inquired, if they are supported,
> > even if there is no TMA or ADF attached to the device. Either this
> > isn't possible ffor the Slide mode or there is a bug in the backend, so that
> > it gets confused with stripes and slides. I will check this.
> >
>

[...]

> > > LUT capabilities: None
> >
> > This attribute normally indicates the size of the gamma and the shading
> > tables, which can be sent to the scanner. The shading table is used for
> > the calibration process, so this is the reason, why 'calibration by backend'
> > will probably not work for you.
> >
> > Did you try the following: Do one or more scans under Windows, and then
> > reboot into Linux *without* switching the power of the device off. If
> > it is a colour calibration problem, it is possible that it is still
> > calibrated, when you start a scan under Linux.
> >
>
> Yes, I tried, but the dark stripe remains. The scanner is constantly on and I booted to Linux with loadlin (so without doing a reset).
>
> > I don't know, why some devices indicate that they do not accept these tables.
> > Before I have seen this only once with the device of one V6USL user, but
> > another device of another user (same model, same FW) had this attribute
> > set to 4096 words, which is ok.
> >
>
> Is it possible that the Phantom 636cx "lies" concerning this capability?

In the meanwhile I do not think so any more. Two people have tried it
with a V6USL, which also often says, that it does not support gamma tables,
and these devices did not accept the gamma tables that these users tried
to send.

[...]

> > > Scanning direction: Right to left

In the meanwhile I have a new release of the backend, where it might
be fixed, that the image is mirrored (see my other mail).

Bernd

-- 
Bernd Schroeder 
Email: mailto:bernd@aquila.muc.de
PGP public key available: mailto:pgp@aquila.muc.de | Subject: send key 

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