Digital Imaging Tutorial

6D. Technical Infrastructure:
DELIVERY

Key Concepts

introduction
networks
  concerns
  speed
  trends
monitors
  evaluation
  image quality
printers
  technologies
  evaluation

MONITORS: EVALUATION
The following factors should be integral to the evaluation process:

Image quality
Size
Ease of use and sophistication of adjustment and calibration controls
Fitness to task
Cost

The market for monitors consists mainly of two very different technologies: CRT (Cathode Ray Tube)-based devices and LCD (Liquid Crystal Display)-based devices. CRTs are built around what in electronics terms is an ancient technology, but still dominate the market, especially for graphics intensive work. However, major improvements in the performance and affordability of LCDs have significantly narrowed the gap between these two technologies.

Here's a rundown of how modern CRTs and TFT (Thin Film Transistor) LCDs compare in several important functional areas, as of late 2002 (a nice chart summarizing the characteristics of the two technologies can be found at http://www.tomshardware.com/display/02q1/020114/lcd-03.html):

Image quality

CRTs typically have better contrast, more accurate color rendition, a wider range of colors, more satisfactory viewing from off-axis (i.e. not looking straight on). They are better at displaying fast changing images, as in movies or animations. CRTs can display a quality image at a variety of pixel dimensions (LCD quality falls off considerably when not used at primary design resolution, called native resolution). CRTs are not subject to dead or stuck pixels, in which spots on the display may be permanently dark or bright.
LCDs typically have brighter images, better focus, less distortion, absence of convergence problems and no flicker.

Ergonomics

LCDs tend to excel across the board in ergonomic factors, being smaller, lighter, and producing less heat and other harmful emissions.

Economics

CRTs are less expensive to buy, especially for large size displays (17" and above).
LCDs are cheaper to operate (lower power consumption), and may have a lower total cost of operation.

Flat panel technologies such as LCD have been under development for decades, and have improved substantially in that time. As noted above, the current generation of LCDs (called TFT or active matrix) can now outperform CRT monitors in many areas. For many routine uses not requiring pixel dimensions above 1024 x 768, the small price premium can be easily justified by other advantages.

However, the accurate display of digital images, especially continuous tone images with large pixel dimensions, remains one of the few areas where CRTs still offer superior performance. In deciding whether to deploy LCDs for the viewing of digital image collections, careful consideration should be given to whether image presentation will suffer from the loss of color fidelity and dynamic range, and whether that loss is of significance to users. Side-by-side comparisons may be the best way to judge. In addition, given that many end users are now purchasing LCDs for personal use, it is prudent to assess how your images will look to users employing them.

Whether a monitor is being used for image editing, quality control, or for end user delivery, the more complete the user controls provided, the greater the ability to optimize performance. Monitors used to come with only brightness and contrast controls. Modern monitors allow considerably more fine tuning. Check a monitor's specifications to determine if the settings critical to your intended use are user-controlled.