DIGITAL digest 3-01
Digital Ins and Outs
Tech Alert is the yearly conference at which the Graphic Arts Technical Foundation (GATF) presents the results of its latest original research studies. At the recently held 2001 conference, studies presented in the digital arena included “Digital Imaging Press Print Attributes,” “Digital Photography” and “Remote Proofing—State-of-the-Art Report.”
According to Dr. Richard M. Adams, study presenter and a GATF research scientist, the digital imaging press study wasn’t intended to be a “shoot out,” whereby output from competing devices is compared to determine the “winner.”
Still, manufacturers of the presses in question were asked to print press sheets from a digital color target provided by GATF. Densitometric analyses were then performed on those press sheets. The study report just includes the raw measurement data, however. It was left up to report readers to interpret any head-to-head comparisons they might choose to make.
Looking at the results in sum, though, it was possible for the researchers to draw several conclusions, according to Dr. Adams. For one, “direct-imaging presses print relatively similar to conventional presses,” he asserts, and “calibration is important for accurate tone reproduction with these devices.”
Adams also says that there is a need to distinguish between the terms “DI” (digital imaging) press, which by virtue of a trademark is supposed to be limited to devices using imaging technology from Presstek, and “DOP” (direct on- press), which is the generic term for imaging technologies from companies such as CreoScitex.
The list of DI presses studied included the Adast 755C DI, Heidelberg Quickmaster DI and Ryobi 3404 DI. The DOP models included the Heidelberg Speedmaster 74, Karat 74, Komori Project D and Screen TruePress.
In at least one sense, the “Digital Photography Survey” was a shoot out. Presenter Greg Bassinger, manager of the GATF Process Controls and Preucil Print Analysis Laboratory, challenged the audience to identify which shot out of six of the same image on a press sheet was taken via conventional photography, versus an assortment of digital cameras.