1Bronzing: An undesired pigment-ink artifact that appears as a mirror-like finish over dense shadow areas and dark saturated colors, especially on glossy-surface prints. 2Dye Ink: Made from organic ingredients that are water-soluble and, in most cases, more susceptible to fading and humidity. However, dye-based inks may produce more highly saturated colors and fewer image artifacts than pigment-based inks. 3Gloss Differential: A visible difference in reflectivity between the paper surface and the inks, found primarily in highlight regions where little or no ink is laid down (for a pure paper white) next to areas where ink is used to make slightly darker whites or colors. 4Matte Black Vs. Photo Black Ink: Nearly all large-format printers contain separate matte black and photo black ink cartridges that are automatically switched by the printer depending on the media loaded. Matte black ink is generally used for watercolor, canvas, plain paper and other specialty surfaces. Photo black inks are used primarily for glossy, luster and semigloss coated photo papers. When the wrong black inks are used, maximum black density and print contrast drop noticeably. 5Pigment Ink: Made primarily from inorganic and insoluble colorants and minerals (i.e., iron oxide) that reflect or absorb specific wavelengths of visible light. These are ground into microscopic particles that are suspended in a liquid binder. As a result, pigmented inks tend to settle closer to the surface on most papers, but are far more resistant to light fading and humidity. 6Printer DPI Vs. Image File DPI: All printer specifications include a dpi (dots per inch) resolution figure that describes the maximum number of ink dots that can be placed in a given area. Examples include 2400x1200 dpi for the 24-inch Canon imagePROGRAF iPF6300 and 2880x2880 dpi for the 24-inch Epson Stylus Pro 7890. Those printer dpi ratings often are confused with the dots-per-inch resolution of an image file (better defined as pixels per inch, or ppi.) For the best quality and speed results when printing enlargements, the resolution of an image file needs only be between 200 and 250 dpi (or ppi). Therefore, a 16x20-inch print would look best if it came from a file containing at least (16 x 200) x (20 x 200) = 12,800,000 pixels (12.8 MP).
[ Costs Per Print ]
It can cost less per print to use a large-format pro printer than a lower-priced consumer model. How is that possible when the ink cartridges that you typically load into a large-format printer cost far more than the inks used in a 13x19-inch desktop printer? The answer: Economy of scale. For example, it costs $60 for each of the nine cartridges used in the 17-inch Epson Stylus Pro 3880 compared to $13 each for the nine cartridges used in the 13-inch Epson Stylus Photo R2880. That totals $540 to replace all 3880 inks, and only $117 to replace the R2880 inks. But that’s an apples-to-oranges comparison, since each of the standard ink cartridges in the large-format 3880 contain 80ml of ink—for a cost of $0.75 per ml—compared to approximately 11ml in each R2880 cartridge—for a cost of $1.18 per ml. As you move up into the 24-inch printer category, the price per ml drops even further: The nine standard cartridges in the Epson Stylus Pro 7890 cost $90 each but hold 150ml, for a price of $0.60 per ml. Optional higher-capacity 350ml ($160 each, or $0.46 per ml) and 700ml ($240 each, or $0.34 per ml) cartridges also are available. Assuming that each printer uses the same quantity of ink to print the same-sized enlargement, and based on a test of ink use for the R2880 at www.printerville.net, the cost for the ink used making a 13x19-inch color print could drop from $2.77 (Epson R2880) to $1.08 (Epson 7890 with 700ml cartridges.) Visit www.printerville.net/2008/09/14/epson-stylus-photo-r2880-review.
In addition to ink savings, most large-format printers can be loaded with roll media in various widths and lengths (ranging from 40 to 100 feet). Cut-sheet sizes generally stop at 17x22 inches, and 24-inch and wider media is available only in rolls for most printers. Once again, you may pay more up front for a roll of photo paper than for a box of cut sheets, but rolls usually hold more paper, are easier to ship and store, and typically cost 10% to 20% less per square foot than cut sheets. That’s not as great a savings as that of the inks, but over time, both differences could wind up saving you as much as you paid for the printer, plus labor costs for loading cut sheets and changing out smaller-capacity ink cartridges.
Granted, it takes time to make your own prints and maintain your own large-format printer; however, the cost per do-it-yourself print is usually far lower than the cost for a custom print at a pro lab, and thanks to the built-in color calibration and accurate color profiles that ship with most 24-inch printers, it’s even possible for a novice to match the image on a calibrated monitor to a print on the first try. In addition, custom profiles (costing under $100) can be purchased for third-party fine-art and photo papers. (Bear in mind that Adams—and today’s serious landscape photographers—made/make a number of test prints to get everything perfect. This runs up the cost if you’re just making a single print of an image, but is relatively minor if you’re printing an edition.)
If you’re in a hurry, no lab can beat the 10- to 15-minute turnaround time for a 24x36-inch print or less than two minutes for a 13x19-inch print. When using roll media, you also can stack multiple print jobs in a print queue and send them all to the printer at a time you choose, thereby maximizing printer efficiency and power usage.
Michael J. McNamara is a photovideographer who’s been reporting on imaging products and trends since 1989. His blog and a portfolio of movies and still photos can be found at www.mcnamarareport.com.