These days most large format printers come with a basic driver which will produce a reasonable picture, but if you're using it for production of screen separations a RIP is a vital part of the equation.
RIP stands for Raster Image Processor, a piece of software that takes a Postscript file and converts it into dots that the printer understands. A hardware RIP is simply a software RIP in a proprietry case that's really difficult to upgrade. The advantages of the RIP stem from the flexibility of the Postscript language, a printer orientated language that allows separations, trapping and halftone information to be included within the file.
IMAGESETTER
If you are doing halftoned work use of a RIP is almost compulsory, you can get away with the halftoning tools in Photoshop/Illustrator or Corel to a certain extent but the quality will be low and there is little fine control. With a screenprinting RIP such as Wasatch, you have the choice of halftone line rulings, dot shape, angles and a special trick called 'extra tonal resolution' which adds greyscale colours - smoothing out the postscript banding that often occurs with low-resolution devices. No one likes to see white lines between blocks of colour, so Postscript allows trapping to be specified, where one colour overlaps another slightly. Any misregistration of the screens during printing will not result in a ruined print. RIPs have sophisticated nesting facilities where several images can be arranged on the film to give the most efficient layout. Cropping of images is simple, just draw a box around the bit you want to print and add it to your layout. Should you need larger films, the image can be broken into tiles, complete with registration marks for reassembly. Windows drivers often have limited lengths, if you need greater, say for banners, you need a RIP. The RIP allows explicit control over the ink drop size and the resolution, this allows the density of the film to be controlled.
None of these are impossible without a RIP but you would need to be very, very good with DTP software and have far too much time on your hands. If there is one reason to get a RIP it's that it makes your life easier, simpler and more profitable.
Why Do I Need a RIP For a Large Format Imagesetter Printer? IMAGESETTER
No comments:
Post a Comment