Acronym for Desktop Colour Separation. Originally introduced by Quark, it splits an image into five separate files: a low-res preview plus the four process channels, CMYK. Uses - bureaus can supply a designer with the low-res image only, at about 10% the total file size, these files are imported as FPO (For Position Only) into the layout. The FPOs are linked with the high-res files immediately prior to output. The low-res is useful too as it reduces the laser proofing time during the design process dramatically. There are two Photoshop DCS formats: DCS 1.0 and DCS 2.0 - DCS 2.0 supports a fifth, spot colour, channel.