[sane-devel] How i can use 2 or more scanners at the same time??

[abel deuring]

On 23.07.2008 08:20, kid2k4 at email.it wrote:
> Thanx all for the answers and advice(s).
> 
> To  Jeremy Johnson:  
> Very cool the program higin, it's possible to make a scrip for make his 
> job in real time?
> 
> To Allan:     
>   Yes!! I know.. the software it's the last of our problems.. very 
> usefull your advice. For the rigid frame .. no problem, we work good on 
> iron, steel or aluminium. We aren't think about motor question e 
> dataloss, thank.
> 
> To Gerard Klaver:
>    no cameras says our chief!!! Sic!! was my first idea for solving the 
> problem scanner. Thank for information on the size of scanned photos.
> 
> This is the link <http://www.mediaintegrati.it/manhere> to a 
> presentation of our project.  We need to build a scanner gate bigger 
> like a door. The visitor may think about a gate the scan (with a green 
> scenografic led up & down) his
> body and take a picture (we also think about a rendering in 3d of the 
> scanned image or an avatar crated in real time) put into some different 
> contests of web sites or web cam sites.
> If someone have an idea about the making of the scanner-gate and the 
> software controlling pleas e post that. I hope to work with some 
> developers in Italy but want to take a fine project before.
> The power of open-source software help me so much.

I like this project! And I believe that I understand why your boss does
not want to use cameras ;)

Anyway, I think there a more problems in addition to those mentioned by
others, mostly related to optics and illumination.

For a start, take for example a puppet (or any other  3-dimensional
object roughly of the size of an A4 sheet), hold it, say, 20 or 30 cm
above the glass pane of a scanner and start the scan. You will mostly
like get a very blurred image, because scanners do not have a large
depth of field (comparing the German and Italian version of the manual
of my camera, this is profonditá di campo in Italian). If you do not use
any additional illumination, the image will probably also be a bit dark.

If you "scale" this problem to the physical size required for your
project, things will be much worse, I'm afraid.

I think you should ask an engineer or physicist to design a specialized
scanner from scratch: You'll need somebody who understands how the light
scattered from the scanned object is "mapped" through lenses onto the
optical sensor and who knows how design an optical and mechanical setup
for your project. My personal feeling is that it might be easier to buy
a CCD sensor, lenses, mechanical parts, lamps, electronic parts etc
separately so that they match the requirements of your project than to
modify an off-the-shelf scanner.

Abel