35, 62, 61, 36... Then, using Page Setup or Print (under the File menu) one could print two pages per sheet, double-sided. The result could then be folded in half along the width, arranged as 8-sheet signatures, sewn, and bound. Post-design imposition. A post-design application might take a PostScript or PDF file in single pages and produce a new PostScript or PDF file with imposed sheet layouts for printing. A variation of this is to take a large number of single-page source files as input. This is especially suitable for a magazine or newspaper, where pages may be worked on by different groups simultaneously. Print driver imposition. Some printer drivers enable the source application's single-page printed output to be sent to the printer as full sheets. This is not often found in professional production, but is popular for such things as booklet printing on office laser printers. A variation of this offers the ability to print layouts as an option in the application. Output device imposition. This is sometimes called "in-RIP imposition". This allows regular pages to be printed by any suitable means, and the output device handles imposition. While this offers the advantage of enabling specific tuning of the imposition for an output device, the cost is that there is no preview until the output is produced. This may mean a costly printing plate that takes some time to produce, or even (with a digital press) errors in finished copies: expensive mistakes are possible. Where an imposition layout is viewed on screen, it may be referred to as a printer's spread. This is used to contrast with reader's spread, which shows a finished printed piece on screen as it will appear to the reader, rather than the printer; specifically, in a reader's spread for a typical book, pairs of facing pages are shown side-by-side (that is, pages 2 and 3 together). Imposition proof The imposition proof is the last test that is performed before beginning the print run. This test is performed to verify, through the formation of a prototype, that the imposition was successful. Typical checks are that the pages are on the correct spot and the crossover bleeds work. It cannot be used as a check proof for images or colors or layout because it is printed on a large, low-resolution inkjet printer. Since the inkjet printer can print on only one side of the paper, the