Printed test sheets: http://www.diytrade.com/china/4/products/1707979/IEEE_Resolution_Chart.html?r=0 or http://www.aig-imaging.com/mm5/merchant.mvc?Screen=PROD&Store_Code=AIIPI&Product_Code=QA-60&Category_Code=Video-Scanner-Resolution-Charts At 04:54 PM 5/2/2009 -0700, [log in to unmask] wrote: >On 5/1/09 8:27 PM, Lars Aronsson wrote: >>Does anybody have a printed test sheet that we can scan or photo, and >>then compare the resulting digital images? It should have lines at >>various densities and areas of different colours, just like an old TV >>test image. Can you buy such calibration sheets? > >archive.org scans typically include a color card target >image near the back (or front) of the book, e.g. > >http://www-steve.us.archive.org/public/data/eg/birdsthateverych00doub/birdsthateverych00doub_jp2/birdsthateverych00doub_0371.jp2 > >typical specs for our scanning rig (scribe) are roughly: > > 1 8x8x5' scribe structure > 2 Canon EOS 5Ds > 2 light boxes > 1 orthogonal glass platen and cradle > 1 foot pedal, pulley system > Linux PC > LAMP stack > custom web-based UI > gphoto, imagemagick, leptonica, rsync > fast internet > > >we scan over 1,000 books a day with about 100 scribes like this. > > >[log in to unmask]