[sane-devel] Backend for plustek Opticbook 3600

[Chris Berry]

On 02/24/2010 10:33 AM, Pierre Willenbrock wrote:
> stef schrieb:
>    
>> Le mercredi 24 février 2010 03:00:16 Chris Berry, vous avez écrit :
>>      
>>> Hey Stef,
>>>
>>> I think I have sorted out the white shading data but the black is still
>>> a mystery. I have uploaded some files to the project site (here
>>> http://sites.google.com/site/bez625/updates-1/update240210 ) these are
>>> at shading lines set to 400 but for the scan to work even a little bit I
>>> needed to change the lines to 20 (this removes the light blue lines at
>>> the bottom of the white_shading.pnm).
>>>
>>> As you will be able to see the black_shading400.pnm is all white, I have
>>> no idea how to alter this. You can see from the white_shading400.pnm the
>>> full calibration area so I am at a loss really. Have you encountered
>>> this problem before?
>>>
>>> Thanks
>>>
>>> Chris
>>>
>>>        
>> 	Hello,
>>
>> 	judging from the 2 pictures, there is no black area to scan. You should then
>> rather use the GENESYS_FLAG_DARK_WHITE_CALIBRATION (like the lide 35) flag
>> instead of GENESYS_FLAG_DARK_CALIBRATION. The shading data will be taken from
>> an all white area and black data will be inferred from the small black areas
>> still in the picture.
>> 	
>>      
> GENESYS_FLAG_DARK_WHITE_CALIBRATION is just a way to scan the black and
> white strip in one go. Chris, you should try to figure out if the
> backend goes through genesys_dark_shading_calibration with
> GENESYS_FLAG_DARK_CALIBRATION, and if so, why the lamp does not switch off.
>
> Regards,
>    Pierre
>
>    
Hi Pierre / Stef,

I was wondering the same thing but the lamp does indeed go off. I'm not 
sure why the scan is so light, I had no idea which area it was scanning 
from.... I have been playing with the dark_white calibration and i seem 
to be getting somewhere, here ( 
http://sites.google.com/site/bez625/updates-1/update240210lateron ) are 
some scans.

Should I abandon the work with DARK_WHITE and see if I can fix the issue 
with DARK_CALIBRATION?

Chris

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