The canary refers to the somewhat outstanding, pale color of a small bird found in the Canary Islands thus giving the color its name. It's a soft, bright yellow that was used by letterpress printers when printing three-part invoices -- three sheets white on top, yellow in the middle and pink on the last sheet. A piece of carbon paper was inserted between the first and second sheets. When put together, the canary sheet offered contrast to the carbon paper image and likewise with the pink sheet. For whatever reason, the canary sheet always made it very easy to read the copy that was usually in black. If you use a blank white sheet of paper to cover your chips to scan, the whiteness of the paper...in my opinion...reflects brightly on the optics, changing the color of the chip..in this case orange. So, in my opinion, canary colored paper diffuses the brightness by absorbing the scan light thus allowing a true scan of colors. There is no scientific proof, but old printers chose those colors to make the best hand printed invoices of their time. Better printing companies still use the three-part invoice printing method and the three colors. Hope this helps.