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SharonH
05-14-2009, 11:29 AM
Question:
Does the Fiery calibrate to a known standard?

Answer:
Quick Answer:
There is not a single answer to the “best” calibration target to use, especially with laser printers. A good calibration target is one which can be maintained and reproduced over time, without limiting the color gamut of the printer, while allowing smooth gradients with detailed shadows and highlights

The Fiery Calibration curve is not based on any standard but based EFIs experience with laser based devices and how an ideal calibration target should look like in order to get the best color quality.

Long Answer:
“Is the Fiery calibration target based on an ISO Press standard?”
No. Fiery systems feature calibration targets optimized for the printers they drive. Which calibration target to use is not dictated by the device you simulate, but by the device you drive. Fiery driven printers can be used for production and for proofing (simulation). There is no need for the simulated press and the output printer to have the same calibration targets. If you calibrate both according to their own technology, you can expect the proofer to be able to simulate a press.

Presses and laser printers are very different technologies.

A press is applying ink on its media in a generally natural and predictable manner. On a typical media, ink is absorbed by the paper. For all values except 0 and 100%, more ink end-up covering the media than what the color plates are requesting. This difference is at its maximum around 50% specified dot coverage. An operator stays near the press and makes sure that the press “calibration target” is maintained. This target is always as follow: nothing should print on the sheet at 0% input; 100% should entirely cover the sheet, without over saturating it. For the behavior between 0% and 100%, it used to be dictated by a smooth progression, independently optimized for each ink. Recent trends will use halftones or procedures to optimize the ink response based on relationships between the inks. Both methods deliver excellent results.

Laser printer technology is fundamentally digital. Toner is applied using magnetic properties, which are greatly affected by environmental conditions (like heat and humidity), the nature of the paper (like its substance, coating and thickness) and of course specific electronics in the printer. Manufacturers determine for each “print mode” what they consider to be an ideal response. They take into consideration additional factors, like the toner coverage and print volume expected by typical applications on a printer model. Some laser printers have “s” shaped curves; some have almost linear responses; some almost have the traditional press “dot gain” curve. All this to say that there is no inherent “natural” behavior to laser printers. In fact, some printer models offer more than one “natural” behavior for the rip to use!