Digital Printing - What is RIP?

My brother, the artist, asked me, the electrical engineer, what RIP is. He was looking at large format printers on Epson's web site and said they recommend this thing, but no where on their web site do they define it. I took a look myself, and found references to it, but never a definition.

It's apparently some item of software that runs as some sort of printer driver or server.

Can somebody explain it to a simpleton such as me?

Quick search on google yielded this:

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http://www.repros.com.au/imaging/Q_file_formats.shtml#six

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Hope that helps.

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-klm.

A RIP is a raster image processor... it turns the printer command

language into a raster image at printer resolution. In a typical

laser writer, the RIP function is built into the printer, converting

HP PCL or Adobe PostScript into the raster pattern for the page. High

end color printers also include a CPU to perform the RIP function in

the printer. Most ink jet color printers rely on the computers CPU

and software in the driver to do the RIP. This saves money, takes

advantage of generally fast CPUs but often doesn't have the full

funcitonality of high end RIP engines. There are high end software

RIP engines available, some that RIP PostScript.

With the Epson RIP (about $100) you get Postscript printing. I found that I needed it when printing large text (400 point) on my Epson.

You will also need it for printing EPS images from a page layout program. You do NOT need it to print photos from Photoshop.

Its main use for the graphic designer is to make the local printer a true preview for going to press, as the imagesetters used for film for

plate making are Postscript, the RIP gives you Postscript. If you print locally with anything else, you get differences, some not noticed,

some major (gradients frequently different, character spacing different, etc.). It lets you print CMYK. It makes printing slower, as the

file is first RIPed, then printed. It is software, built into a Postscript printer, or put on a seperate printer driver computer for high end

printers, or put on your computer for the Epson.

Raster Image Processing is a fancy name for the conversion from ASCII

code, bitmap data, or Postscript vector graphics coding, to the on/off

rows of dots that a printer puts down on paper.<br>Older printers used

to do ASCII conversion in hardware, but on some newer printers all the

RIP is done by the host computer. The raster interpretation is all

done in software by the computer for newer Epson inkjets, for

example.<br>You can easily show that the RIP is done by the computer,

by timing the same Epson inkjet attached to a slow computer, and then

a faster one. The printout time is inversely proportional to the

processor speed.<br>Why Epson should sell an expensive RIP engine as a

separate package, when it's already part of the driver software of

every cheapo printer, I don't know.

I'm using an Epson 9500 Large format printer with an Onyx Rip. It

works pretty good and is much faster then the Epson driver. Plus you

can force 1440 dpi bi directional printing on custom papers. I think

you can find more information at www.onyxgfx.com

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JS