Buying A New Monitor
Dot Pitches and Sales Pitches

Copyright 1996 by William K. Walker

 

"As a man is, so he sees. As the eye is formed, such are its powers."
                                          -- William Blake (1757-1827)

 

  If you've come here looking for a detailed technical analysis of the various types of computer monitors, you've come to the wrong place. In the long ALK tradition (hey, four months is a long time in the computer industry), this article discusses the basics of monitor buying for the normal, sane user. If you stretch a point, it might be adequate for a proto-geek. If you are a commercial artist who actually understands things like hue, luminance and color temperature, you should flee the room immediately.
     That being said, here are the main things we're going to worry about: display sharpness (dot pitch), screen size and resolution. We'll look at some of the other issues like refresh rates, controls and preset modes, too, but only after we've dealt with the "big three" basics.

Dotting Your Eyes

Ultimately, the image on your monitor is made up of (brief pause to calculate) about a zillion tiny dots. The smaller and more tightly spaced the dots, the sharper the picture. (No, we are not talking about pixels, that comes later. Sit down.) Computer monitors have a lot of tiny dots, televisions have, relatively speaking, a few big blobby dots. The size and spacing of these dots is expressed by a value called dot pitch. Just about any decent monitor will have a dot pitch of .28 mm or better. Some of the pricier ones will be down around .25 mm (i.e., smaller numbers are better). Don't bother buying anything that has a dot pitch coarser than .28 mm.

Can You See Me?

It doesn't matter if the screen is nice and sharp if it's not big enough for you to see what you are doing. Monitor size is specified by the diagonal distance from one corner of the screen to the other. Since the ratio of width to height is always about 4:3, you only need the one number. Naturally, the computer industry chooses the largest one. The smallest, usable size is 14 inches; a 15-inch monitor is better if you can affford a little extra money. After that, things begin to get expensive.
     Choosing the right size monitor is a function of your budget, your eyesight and your display resolution requirements. The computer builds up the various things it displays on the screen on a grid of picture elements or pixels. A pixel is a sort of standardized dot used to paint images. For example, the default resolution used by Windows is 640x480 -- 640 pixels across by 480 down. This is also the maximum "comfortable" resolution for 14-inch monitors although 800x600 is usable if you've got good eyes and/or an exceptional monitor. If you're really desperate for screen real estate, you can squeeze in 1024x768 pixels, but that's the limit for most 14-inch units and it's not much fun to look at.
     Herewith, the ALK handy, opinionated, official list of comfortable/usable resolutions for the various common monitor sizes for people with normal eyesight:

     14-inch: 640x480/800x600
     15-inch: 800x600/1024x768
     17-inch: 1024x768/1280x1024
     20/21-inch: 1024x768/1280x1024

One more little point here: just because a monitor has, say, a 15-inch tube doesn't mean you get a 15-inch diagonal display area. In fact, the viewable area will certainly be a bit less. If it's a lot less, you might wish to spend your money elsewhere. It's really best to look at a monitor before you buy it. If you can't do that, at least try to pry the viewable area specification out of the salesperson before you decide which brand or model to purchase.

Decisions, Decisions...

So, your primary consideration is probably going to be based on how much screen real estate you need. For what it's worth, I find a resolution of 640x480 to be barely adequate. It's just not a big enough window on the world. If you plan to do any serious word processing or spreadsheet work or web surfing, 640x480 is a real nuisance. Going to 800x600 increases your elbow room by better than 50% and is the lowest really useful screen resolution. In other words, this is a long-winded way of recommending that you buy at least a 15-inch monitor, unless you are on a really tight budget. Bigger is better.

Embellishments

OK, once you've dealt with "how big", there are some other, secondary issues to consider. None of these are quite as important as size, dot pitch and resolution, but they aren't chopped liver, either.

Energy saving features - Just about any new monitor will have features that reduce its energy consumption if your computer supports them. Typically, these monitors will drop down to less power-hungry settings if they stand unused for a period of time.

Reduced emissions - Almost all modern computer monitors meet something called the SWEDAC MPRII reduced emissions guidelines. It's never been conclusively proved that "radiation" from monitors causes health problems, but enough countries adopted this standard that the manufacturers fell into line. This also had one unintended, but beneficial, consequence: Old monitors build up a pretty good static charge on the surface of the screen, making them big-time dust magnets. New ones don't need to be cleaned as often.

Digital vs. analog - A few of the lower-end monitors have analog controls, the rest are digital. How do you tell? Well, basically, if the controls look like a series of little volume-control wheels, it's probably analog; if everything is set with buttons, it's digital. Digitally controlled monitors offer better, more precise control over display dimensions and color parameters. They also incorporate preset modes for the more common screen resolutions. This keeps the display area from shifting around on the screen when you switch between different resolutions -- a real nuisance on early monitors.

Refresh rates - Monitors actually repaint the display many times per second. As a general rule, the higher the refresh rate at a given resolution, the better it looks. Refresh rate capabilities go up with price and size.

Interlaced vs. non-interlaced - Old, obsolete monitors used a technique called interlacing to handle high resolutions. This shouldn't be an issue these days. If the monitor is not non-interlaced, don't buy it.

Flat screens - Your display will look better if the screen has less curvature. Most up-to-date monitors have "pretty flat" screens. A few of the really pricey ones do better.

Plug & Play - Plug & Play is really a Windows 95 thing right now. It's getting to be a fairly common feature on new monitors and it's pretty handy. It lets the operating system query your monitor and automatically make the proper arrangements for resolution and refresh rate settings.

Focus

As with any piece of computer gear, the real key is to focus on the essentials. When it comes to monitors, this means getting a reasonably sharp display (.28 dot pitch or better) and choosing a screen size large enough to handle your desired resolution comfortably. Within these parameters, buy the best you can afford. And, if possible, go to a store and actually look at the darn thing before you buy it.


Reference

Yahoo maintains a fairly extensive collection of links to information about monitors. Here's a good place to start:

Yahoo! - Business and Economy-Companies-Computers-Peripherals-Monitors


Many thanks are due to the following "beta testers" who provided many useful suggestions and a much needed sanity check:

Greg Chapman     David Freeman     Sandy Garrett     Neil Krandall


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Maintained by William K. Walker
Copyright 1996 by William K. Walker
Last update: 04 Dec 96