5. Supported Printers

5.1. Postscript

As for what printers do work with free software, the best choice is to buy a printer with native PostScript support in firmware. Nearly all Un*x software that produces printable output produces it in PostScript, so obviously it'd be nice to get a printer that supports PostScript directly. Unfortunately, PostScript support is scarce outside the laser printer domain, and is sometimes a costly add-on.

Un*x software, and the publishing industry in general, have standardized upon Postscript as the printer control language of choice. This happened for several reasons:

Timing

Postscript arrived as part of the Apple Laserwriter, a perfect companion to the Macintosh, the system largely responsible for the desktop publishing revolution of the 80s.

It's device-independent

Postscript programs can be run to generate output on a pixel screen, a vector screen, a fax machine, or almost any sort of printer mechanism, without the original program needing to be changed. Postscript output will look the same on any Postscript device, at least within the limits of the device's capabilities. Before the creation of PDF, people exchanged complex documents online as Postscript files. The only reason this standard didn't "stick" was because Windows machines didn't usually include a Postscript previewer, so Adobe specified hyperlinks and compression for Postscript, called the result PDF, distributed previewers for it, and invented a market for their "distiller" tools (the functionality of which is also provided by ghostscript's ps2pdf and pdf2ps programs).

It's a real programming language

Postscript is a complete programming language; you can write software to do most anything in it. This is mostly useful for defining subroutines at the start of your program to reproduce complex things over and over throughout your document, like a logo or a big "DRAFT" in the background. But there's no reason you couldn't compute π in a Postscript program.

It's open

Postscript is fully specified in a publically available series of books (which you can find at any good bookstore). Although Adobe invented it and provides the dominant commercial implementation, other vendors like Aladdin produce independently coded implementations as well.

5.2. Non-Postscript

Failing the (larger) budget necessary to buy a Postscript printer, you can use any printer supported by Ghostscript, the free Postscript interpreter used in lieu of actual printer Postscript support. Note that most GNU/Linux distributions can only ship a somewhat outdated version of Ghostscript due to the license. Fortunately, there is usually a prepackaged up to date Ghostscript made available in each distribution's contrib area.

Adobe now has a new printer language called "PrintGear". I think it's a greatly simplified binary format language with some Postscript heritage but no Postscript compatibility. And I haven't heard of Ghostscript supporting it. But some PrintGear printers seem to support another language like PCL, and these printers will work with GNU/Linux (iff the PCL is implemented in the printer and not in a Windows driver).

Similarly, Adobe offers a host-based Postscript implementation called PressReady. This works much like Ghostscript does to provide Postscript support for a non-Postscript printer, but has the disadvantage that it runs only on Windows.

5.3. What printers work?

You can look in several places to see if a particular printer will work. The cooperatively maintained Printing HOWTO printer database aims to be a comprehensive listing of the state of GNU/Linux printer support. A summary of it is below; be sure to check online for more details and information on what driver(s) to use.

The best bet for new printer shoppers is to consult my list of suggested printers. These center around color inkjets and mono laser devices. You can even help support this document and the website by buying from one of my affiliated vendors.

Ghostscript's printer compatibility page has a list of some working printers, as well as links to other pages.

Dejanews contains hundreds of "it works" and "it doesn't work" testimonials. Try all three, and when you're done, check that your printer is present and correct in the database, so that it will be listed properly in this document in the future.

5.4. How to buy a printer

It's a bit difficult to select a printer these days; there are many models to choose from. Here are some shopping tips:

Cost

You get what you pay for. Most printers under $200-300 can print reasonably well, but printing costs a lot per page. For some printers, it only takes one or two cartridges to add up to the cost of a new printer! Similarly, the cheapest printers won't last very long. The least expensive printers, for example, have a MTBF of about three months; obviously these are poorly suited for heavy use.

Inkjets

Inkjet printheads will clog irreparably over time, so the ability to replace the head somehow is a feature. Inkjet printheads are expensive, with integrated head/ink cartridges costing ten times (!) what ink-only cartridges go for, so the ability to replace the head only when needed is a feature. Epson Styluses tend to have fixed heads, and HP DeskJets tend to have heads integrated into the cartridges. Canons have three-part cartridges with independently replaceable ink tanks; I like this design. OTOH, the HP cartridges aren't enormously more expensive, and HP makes a better overall line; Canon is often the third choice from the print quality standpoint; and Epson Styluses are the best supported by free software at the moment. You just can't win.

Lasers

Laser printers consume a drum and toner, plus a little toner wiping bar. The cheapest designs include toner and drum together in a big cartridge; these designs cost the most to run. The best designs for large volume take plain toner powder or at least separate toner cartridges and drums.

Photography

The best color photograph output is from continuous tone printers which use a silver halide plus lasers approach to produce—surprise!—actual photographs. Since these printers cost tens of thousands to buy, Ofoto.com offers inexpensive print-by-print jobs. The results are stunning; even the best inkjets don't compare.

The best affordable photo prints come from the dye-sublimation devices like some members of the Alps series (thermal transfer of dry ink or dye sublimation), or the few consumer-grade Sony photo printers. Unfortunately the Alps devices have poor free software support (the one report I have from a Alps user of the Ghostscript driver speaks of banding and grainy pictures), and even then it's unclear if the dye-sub option is supported. I have no idea if the Sonys work at all.

The more common photo-specialized inkjets usually feature 6 color CMYKcm printing or even a 7 color CMYKcmy process. All photo-specialized printers are expensive to run; either you always run out of blue and have to replace the whole cartridge, or the individual color refills for your high-end photo printer cost an arm and a leg. Special papers cost a bundle, too; you can expect top-quality photo inkjet output to run over a US dollar per page. See also the section on printing photographs later in this document, and the sections on color tuning (such as it is) in Ghostscript.

Speed

Speed is proportional to processing power, bandwidth, and generally printer cost. The fastest printers will be networked Postscript printers with powerful internal processors. Consumer-grade printers will depend partly on Ghostscript's rendering speed, which you can affect by having a reasonably well-powered machine; full pages of color, in particular, can consume large amounts of host memory. As long as you actually have that memory, things should work out fine.

Forms

If you want to print on multicopy forms, then you need an impact printer; many companies still make dot matrix printers, most of which emulate traditional Epson models and thus work fine.

Labels

There are two supported lines of label printer; look for the Dymo-Costar and the Seiko SLP models. Other models may or may not work. Avery also makes various sizes of stick-on labels in 8.5x11 format that you can run through a regular printer.

Plotting

Big drafting formats are usually supported these days by monster inkjets; HP is a popular choice. Mid-sized (11x17) inkjets are also commonly used for smaller prints. Much plotting of this sort is done with the languages RTL, HP-GL, and HP-GL/2, all of which are simple HP proprietary vector languages usually generated directly by application software.