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-------------------------------------------------------------- This story was printed from ZDNet Australia. --------------------------------------------------------------
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Tech Guide: Monitor buying guide By Staff writers, Special to ZDNet April 22, 2004 URL: http://www.zdnet.com.au/reviews/hardware/peripherals/soa/Tech-Guide-Monitor-buying-guide/0,139023417,139145517,00.htm
With so many monitors to choose from, before you buy, it pays to figure out which specs and features will be most important to you.
With so many monitors to choose from, before you buy, it pays to figure out which specs and features will be most important to you. These user profiles will start you off in the right direction.
Home users need to balance price and performance. Extra features such as speakers or USB ports are an important consideration, and depending on where the computer is located, aesthetics may matter as well.
KEY FEATURES:
RECOMMENDATIONS:
 Business user 
Businesses need some bang for the buck, but they are willing to pay for productivity. Bells and whistles are not as important as good image quality and adjustability for viewing comfortably for long stretches.
KEY FEATURES:
RECOMMENDATIONS:
Student 
Academic life often means cramped quarters, with a budget to match. Students need a lightweight, portable design, a small footprint, and image quality good enough for both work and play.
KEY FEATURES:
RECOMMENDATIONS:
Digital photographer/graphic artist 
With too many monitors, what you see onscreen is not what you get from your printer. People working with digital images need excellent colour fidelity and consistent results, and CRTs are generally superior in these areas.
KEY FEATURES:
RECOMMENDATIONS:
In recent years, CRT technology has advanced to the point where there is very little difference in performance among brands. In other words, unless you buy the absolute cheapest CRT, you should be happy with whatever you choose. Read more about CRTs.
Gamer 
It's all about speed for serious game players. Eye-popping image quality is essential, but a lightning-fast pixel-response time is the key to keeping images sharp when the action starts. Although LCDs are making strides, CRTs currently offer the best performance for gaming.
KEY FEATURES:
RECOMMENDATIONS:
In recent years, CRT technology has advanced to the point where there is very little difference in performance among brands. In other words, unless you buy the absolute cheapest CRT, you should be happy with whatever you choose. Read more about CRTs.
Video editor/movie buff 
When digital DeMilles edit the key close-up in their masterwork, they want total artistic control, and they need crisp, accurate images. Movie buffs watching at home will want the same. At this point, CRTs are superior for displaying video.
With so many monitors to choose from, before you buy, it pays to figure out which specs and features will be most important to you.
KEY FEATURES:
RECOMMENDATIONS:
In recent years, CRT technology has advanced to the point where there is very little difference in performance among brands. In other words, unless you buy the absolute cheapest CRT, you should be happy with whatever you choose. Read more about CRTs.
In a marketplace full of so many types of displays, in so many sizes, finding the right monitor can be a challenge. CNET provides some basic information to help you get your bearings.
What is a CRT monitor?
Aspect ratio: The standard proportion in width to height for a computer monitor is 4:3, but some new displays have a wider format: 16:9 or 16:10, designed for viewing movies or HDTV in wide format. Note that a 17-inch wide-format panel has about the same vertical dimension and vertical pixel count as a normal 15-inch panel, so you get about 120 percent of the viewing area of a 15-inch panel. A 17-inch standard panel, however, has 130 percent of the viewing area of a standard 15-inch screen.
With so many monitors to choose from, before you buy, it pays to figure out which specs and features will be most important to you.
Contrast ratio: A spec much hyped by manufacturers (be suspicious of their claims), this is the difference in light intensity between the brightest white and the deepest black. Digital and analog connections: LCDs are digital devices and thus have to convert analog (VGA) signals before they can be displayed. A graphics card with a digital video interface (DVI) can send the signal straight to the display in digital format--no conversion required. Most LCDs come with an analog input (featuring a D-shaped connector that has 15 pins arranged in three rows, sometimes labelled D-Sub), some come with both, and only a very few come with just a digital input. Nevertheless, at this point, most monitors do such a good job of signal conversion that digital connections are not as important as they used to be.
Luminance: Brightness; a measure of how much light a panel can produce. Luminance is expressed either in nits or candelas per square meter (cd/m²). A measurement of 200 to 250 nits is OK for most productivity tasks; 500 nits is better for TV and movies. Pixel-response rate: This refers to how quickly a pixel can change colours, measured in milliseconds (ms); the fewer the milliseconds, the faster the pixels can change, reducing the ghosting or streaking effect you might see in a moving or changing image. In general, manufacturers' specifications rely on best-case scenarios; real-world performance could be slower. A maximum of a 12ms-to-15ms response time across the spectrum is required for gaming or viewing television and movies without ghosting or streaking. We've only just begun to see LCDs with superfast pixel-response times, such as Samsung's SyncMaster 172X and BenQ's FP767-12. Portrait/Landscape modes: Some LCDs pivot so that the longer edge can go horizontal (Landscape mode) or vertical (Portrait mode). This feature can be useful for desktop publishing, Web surfing, and viewing large spreadsheets, but don't pay extra for it if you won't use it.
Resolution: Make sure you are comfortable with an LCD's native resolution before you buy it. Remember, an LCD that scales its image to a nonnative resolution will never look as good. Viewing angle: The physical structure of LCD pixels can cause the brightness and even the colour of images to shift if you view them from an angle rather than facing the screen directly. Take manufacturer's specifications with a grain of salt and make your own observations if possible; viewing-angle issues become more critical as panel size increases.
Bandwidth: The rate in megahertz (MHz) at which a CRT can process information. As you approach the bandwidth limit, thin black or white lines appear gray because the electron beams cannot turn all the way on or off fast enough to keep up. Generally, the higher a CRT's bandwidth is, the faster its refresh rate is at any resolution, and the better its image quality.
With so many monitors to choose from, before you buy, it pays to figure out which specs and features will be most important to you.
Convergence: Colour CRTs rely on three separate electrical beams to project simultaneous red, green, and blue images; these combine to form a full-colour image. If these beams are not precisely aligned, the red, green, and blue portions of the image may not overlap correctly; the image will look unfocused and will have visible colours along the edges. When the three beams converge correctly at all points on the display, you get a perfect image.
Maximum refresh rate: If an image refreshes too slowly on a CRT, you may notice a flicker. You want at least 70Hz at the resolution you intend to use. This becomes more of a factor as the screen size gets larger, as people are more susceptible to flicker in their peripheral vision. Power consumption: CRT power consumption is typically specified in watts. A typical 19-inch model may draw 130 watts when operating--that's more than two standard 60-watt lightbulbs--and will generate a good deal of heat. Screen size: CRTs specify the diagonal dimension of the entire picture tube. This is one to two inches larger than the viewable image size (also measured diagonally).
Image quality, the most important feature of a monitor, is also the hardest to judge. Good is a subjective term, so relying on the judgment of reviewers (such as us) may not get you exactly what you want. Further, like a snowflake, every monitor is unique. There can be significant differences from one monitor to another -- even among the same make and model. It's unrealistic to expect to run a comprehensive diagnostic on a monitor before you buy it, but here are some of the most important qualities to look for when choosing a CRT or an LCD. We've also included a few simple tests you can do in the store to assess image quality.
Tips and tricks: assessing LCD image quality
CRTs: what to look for
Tips and tricks: assessing CRT image quality
As with any high-tech component, monitors come with all sorts of connections, accessories, and extra features. Some add more value than others.
CRTs rarely provide support for digital (DVI) signals; DVI support is found primarily on LCDs. The advantage of digital signals for LCDs is of much less importance now than it was a few years ago. Analog (VGA) signal processing has improved to the point where only the most discerning eye can notice any difference. Most LCDs that support digital signals also support analog signals, so you won't need a special graphics adapter to use a DVI display.
To take advantage of the digital connection, you'll need a graphics adapter that has a DVI-I or DVI-D connector, and you may also need a DVI cable (many LCD monitors come with only an analog cable). DVI-D refers to a digital-only connection, and DVI-I means that the connector can carry either digital or analog signals. Analog inputs, sometimes labelled D-Sub, have a D-shaped connector with 15 pins arranged in three rows. Extra features
Adjustability: Most CRTs sit on stands that let you tilt and swivel the screen, but LCDs are generally more flexible. Some include a swivel feature, many offer height adjustability, and most can tilt forward and backward. Some LCDs' panels can also pivot between Portrait and Landscape modes, making legal-size documents and Web pages easier to view. LCDs can be attached to VESA-compatible mounts, which connect to third-party wall mounts or swinging arms.
With so many monitors to choose from, before you buy, it pays to figure out which specs and features will be most important to you.
Audio: Some monitors offer audio functions, either as standard items or as optional accessories. These may include a headset jack, volume control, or embedded speakers. In general, these speakers are of limited quality, and an inexpensive $40 speaker set from a computer or office supply store will often provide much better sound. Cable-feed systems: Many LCDs have some mechanism to manage signal and power cords.
USB: Many displays have USB ports. Typically, they are not powered hubs, but simply convenient ports to connect a keyboard or a mouse, thereby reducing the tangle of cables that run back to the computer.
Video/TV: As work and entertainment products continue to converge, many monitors now have features designed to take advantage of television and movie content. Some include TV tuners and connectors for video signals from cable television systems or antennas. Some have connectors that accept composite or S-Video input signals from entertainment devices. Wireless: Some displays are doing away with cables completely. ViewSonic's Airpanel uses Microsoft's Smart Display technology to establish a wireless connection with a desktop computer. Somewhere between a tablet computer and a remote display, it gives you more freedom to move around. Other: LCDs using Philips's LightFrame technology and various CRTs using high-brightness features allow you to increase the amount of light for a given window or the entire screen. This can be helpful when viewing movies or other graphics images. BenQ's FP591 has inputs for CompactFlash, SmartMedia, and SD/MMC removable media cards that let digital photo enthusiasts see their pictures without a PC.
When choosing a monitor, consider the company behind it.
Aperture grille: In some CRTs, the aperture grille is a series of wires stretched vertically down the inside of the monitor to mask the beams from the electron guns at the back of the tube. In other types of monitors, this function falls to a perforated metal plate called a shadow mask. Some users prefer the image quality of Sony Trinitron monitors, which use an aperture grille; others notice the faint horizontal shadows cast by the grille's tensioning wires and prefer other shadow-mask designs.
Bezel: The frame around a CRT's or LCD's screen. Convergence: Colour CRTs rely on three separate electrical beams to project simultaneous red, green, and blue images; these combine to form a full-colour image. If these beams are not precisely aligned, the red, green, and blue portions of the image may not overlap correctly, degrading the overall image quality. When the three beams converge correctly at all points on the display, you get a perfect image. CRT: Cathode-ray tube; a big bell of glass with electron guns at one end and a viewing screen at the other. Televisions and computer displays both use this imaging technology and are often simply called CRTs. Display size: A display's length (in inches or centimeters) taken diagonally from one corner to the opposite corner. Unless it specifically states viewable screen area, a CRT's measurement encompasses the full face of the picture tube, including the part concealed by the bezel. On an LCD, only the viewable screen is measured. Dot pitch: In CRTs, the distance from one pixel to the next-nearest one. The larger the dot pitch, the grainier an image looks. Electron gun: A colour CRT contains three electron guns that shoot electron beams, causing red (R), green (G), or blue (B) phosphors on the inside front of the screen to light up. Footprint: The amount of space a monitor takes up on your desk, including the display and its base. LCD: Liquid-crystal display; created by sandwiching electrically reactive, liquid-crystal material between two electrodes. The substance can be darkened or lightened by applying and removing current. Liquid crystal: A material with some of the properties of solid crystals, such as diamonds, and some of the properties of liquids, such as water. As a result, the material can both flow as well as affect the path of light, depending on how the individual molecules are aligned. Molecule: The smallest portion of a material. For some materials, the physical size and shape of the individual molecules affect the overall properties of the material. For example, the individual molecules of liquid-crystal material can alter the path of light and can be induced to align in specific ways in response to physical or electrical influences. It is these characteristics that make them useful in creating displays. Native resolution: The physical structure of some types of displays, including LCDs and plasma panels, defines how many pixels can be displayed at once. The display produces the sharpest picture when used at its so-called native resolution. Other types of displays, such as CRTs, create pixels independently of the physical structure of their screens and do not have a native resolution. As a result, a CRT's image quality is generally the same across a range of resolutions. Nits: A unit of measure for luminance (a monitor's brightness); equivalent to candelas per square meter (cd/m²). Phosphor: A substance that can produce red, green, or blue light when excited by an energy source, such as the electron beam in a CRT. Phosphors are arranged as either dots or stripes on the inside face of a CRT screen. Pixel: In a CRT, phosphors grouped in RGB triads (one each of red, green, and blue) are called pixels. The hundreds of thousands to millions of pixels in a display create images. Refresh rate: The frequency at which a CRT's electron guns redraw the image; measured in hertz (Hz). One hertz equals one cycle per second; a 70Hz refresh rate means that the entire screen is redrawn 70 times per second. Resolution: For both CRTs and LCDs, the number of pixels in the whole image. For example, a resolution of 1,280x1,024 pixels means that 1,024 lines are drawn from the top to the bottom of the screen, and each of these lines is made up of 1,280 separate pixels. Screen geometry: A description of how accurately lines and shapes are represented on the display. LCDs almost always have perfect geometry because the display information is mapped to specific physical pixels on the display. CRTs may have problems with screen geometry; larger screens and flat-faced models have particular difficulty controlling electron beams with precision. As a result, vertical lines may be noticeably curved at the edges of the display, and circles may appear oval or egg-shaped. The best CRT monitors include controls that let you adjust the screen geometry; still, it can be difficult to adjust it perfectly in all regions of the screen. Shadow mask: A metal plate with holes in it that selectively blocks the beams from the electron guns in the back of a CRT. Stripe pitch: Monitors using an aperture grille or a striped mask have phosphors arranged in vertical stripes. Stripe pitch is the distance from a stripe of a given colour to the next stripe of the same colour. A smaller stripe pitch means that the monitor can display higher-resolution images more accurately. Stuck/dead pixel: A pixel on an LCD that is either permanently on (stuck) or permanently off (dead). Subpixel: Full-colour displays are made by combining red, green, and blue light in varying degrees to produce different shades of colours. In a display with a fixed pixel structure, such as LCDs or plasma panels, the red, green, and blue light comes from adjacent cells in the display's physical structure. The light from these three subpixels--one for each colour--combine to create a single pixel. There are also pixel structures that do not rely on three subpixels. SVGA: Supervideo graphics array; a display mode with a resolution of 800x600 pixels. TFT: Thin-film transistor; refers to the switching devices placed in each liquid-crystal cell in an active-matrix LCD. TFT screens are brighter and more readable than passive-matrix LCDs, but they consume more power and are generally more expensive. Trinitron: A type of CRT developed by Sony that differs from standard tube types in that it employs an aperture grille instead of the usual shadow mask. SXGA: Superextended graphics array; a display mode with a resolution of 1,280x1,024 pixels. UXGA: Ultraextended graphics array; a display mode with a resolution of 1,600x1,200 pixels. VGA: Video graphics array; a display mode with a resolution of 640x480 pixels. Viewable area: The diagonal length of a CRT's viewable screen. XGA: Extended graphics array; a display mode with a resolution of 1,024x768 pixels.
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