HP Designjet H35000, H45000 and ColorSpan 5400uv Series Printers - Selecting a Print Mode

The Designjet H series of UV-curable inkjet printers offer numerous print modes that can be selected to achieve higher quality output or faster throughput. This knowledgebase article guides you through the different choices to help you select the best configuration for a particular output requirement.

There are three basic print modes: Billboard, Production, and High Quality.

• "Billboard" mode produces output that is suitable for larger pieces that will be viewed at a distance. Billboard mode is the fastest mode, but there may be print anomalies visible at close distances. When viewed at an appropriate distance, these print anomalies are not discernable to the average viewer.
• "Production" mode combines good quality output with good speed. Production mode will produce output that appears free from anomalies when viewed at a range of several feet or more. Production mode is well-suited for photographic images and other files that are "busy". Most solid colors can be reproduced in large areas without any anomalies, but some selected colors may produce one or another types of anomalies that may be objectionable under closer viewing conditions.
• "High Quality" mode is the slowest of the three modes but produces all types of output best. Solid colors that may have been problematic in Production mode will generally look better in High Quality mode. High Quality is also best suited for very heavy media types.

After selecting the basic print mode, you must next choose between Bidirectional and Unidirectional printing.

• Bidirectional applies ink as the carriage moves in both directions, right-to-left and left-toright. Bidirectional printing is required to achieve the maximum possible speeds in any of the modes.
• Unidirectional applies ink in one direction or the other. Unidirectional printing may produce better output when the media is not very flat or has other surface irregularities. If choosing either unidirectional configurations, you must also select which lamp you want to use.
  • Leading lamp: If the leading lamp is used, the ink drops have more time to spread after they hit the media before being cured by the lamp on the return pass of the carriage. This can smooth out the output appearance somewhat.
  • Trailing lamp: if the trailing lamp is used, the ink drops are cured immediately after hitting the media. This will achieve a finish similar to that of bidirectional printing.

If printing in a unidirectional configuration, one UV bulb will accumulate hours of use faster than the other. You should periodically change the configuration between Unidirectional-Left and Unidirectional-Right so that the bulb hours remain balanced. Unbalanced bulbs emit different strengths of UV light, which will create output anomalies in a bidirectional configuration.

Both Production mode and High Quality mode offer an additional option called "Fine Text". Fine Text changes the speed of the printer carriage to half of its normal rate. This allows for a very accurate drop placement with very little overspray. This option can be used when printing very small type and/or finely detailed lines, such as a map or similar output.

Because the speed of the carriage slows, the UV lamps spend more time over the media. Some media react to the heat of the lamps by bowing. Be careful when selecting the Fine Text option on media that are sensitive to heat. You may need to introduce a Printing Delay to allow heat to dissipate from the media after each pass of the carriage.

Each of the items discussed above--print mode, bidirectional and unidirectional, and the Fine Text option--are selected through the printer's control panel. Print resolution--1200x600, 600x600, and 600x300--is selected through the print server. As with the print modes, the demand for higher quality (e.g., 1200x600 d.p.i.) requires slower print speeds.

• 1200x600 d.p.i: the printed output will have a physical resolution of 1200 dots across by 600 dots down. Because this resolution uses additional passes to achieve the higher resolution, print speed is slowed.
• 600x600 d.p.i: the printed output will have a physical resolution of 600 dots across by 600 dots down.
• 600x300 d.p.i: the printed output will have a physical resolution of 600 dots across by 300 dots down. This resolution is available only for Production mode.

"Color Set" refers to the number of colors used for printing. The 5440 and 5445 are CMYK-only printers, so only a single color set is available. The 5460 and 5465 are CMYK plus light cyan and light magenta--notated as CMYKcm--but can print using either "four color" CMYK or "six color" CMYKcm. This configuration is made by selecting the desired profile on the print server prior to printing. The choice of color set will affect output quality and total ink usage, but does not affect speed in any way.

• CMYKcm: six-color printing produces the highest quality output. The light-density cyan and magenta are used to fill in transitions, midtones, and highlights that would otherwise require a mixture of full-density drops and whitespace to create the illusion of color. This creates the "apparent" resolution that is perceived to be greater than the physical resolution of the print. Total ink consumption is increased because more drops are used.
• CMYK: four-color printing produces good quality and is excellent for simple signage, text, solid colors, or anything that will be viewed at a distance.