as someone else suggested: big roll of paper (or plasticised paper, whatever survives well enough
being shot without totally disintegrating... using black paper might make your life a whole lot
easier later on...)

feed paper into one side of the window, and take it up on another roller on the other side.

shoot paper from various distances or whatever else you want to do, scrolling on roll each time.

as a second process (or as part of the same process if you like) run the paper through a scanner of
some kind...

[one resonable solution, depending on how much time/ money you want to invest might be to build your
own custom scanner (assuming you can't get a suitable one off the shelf - i have no idea about that
possibility). back-light the paper with an even(ish) source of illumination (more even lighting will
make the filtering bit later a bit easier), use a lense arrangement to focus the image onto a linear
ccd array (you can get these at very high resolutions for not too much dough) and scroll the paper
to scan the whole thing - no need to worry about linear speed really, so long as you measure the
movement and grab a scanline at the right time.
throw the resultant image through some filtering to give you a good contrast, scan picture however
you want to get the info you are after]

regards,
Simon

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