A Photopolymer gravure is an intaglio (engraving) print made from a photo sensitive gelatin coated steel plate developed with  a water etch.  Once hardened, it is inked and run through a printers press similar to a copper or zinc plate using a high quality watercolor paper as the receiving substrate.  I principally use 8x10 negatives of night photographs as my subject.  They print as a negative image.