Last week’s quiz presented various different possibilities for seeing more on your Mac’s desktop. The correct answer was that all of the options enabled you to see more, although they work in different ways. Let’s look at each of the answers, since although most of you probably know this information (about two thirds of the quiz respondents answered correctly), it’s good to pass on to friends or relatives who are less experienced with the Mac.
Adjusting screen resolution means changing the number of pixels that define the height and width of your screen. You can see more on your desktop running at a resolution of 1024 by 768 than at a resolution of 640 by 480 – although, depending on your monitor, a lower resolution may be more comfortable for reading text or other tasks. Use the Monitors control panel or the screen resolution Control Strip module to adjust your screen resolution. You can adjust screen resolution on the fly, though items on your desktop may be rearranged if you choose a smaller size (and if you change resolutions frequently, check "Tools We Use: Desktop Resetter" in TidBITS-466 for details on a utility that remembers desktop icon positions). Many novice users don’t realize they can change screen resolution and end up working at a resolution that’s less than ideal for the type of work they do or for their eyesight. When we set up Macs for friends or relatives, we always show them different screen resolutions and ask which they prefer.
Adding another monitor is one of the Mac’s greatest unsung features: most Macs can drive two or more monitors that combine together to form a single extended desktop. Multiple monitors are a great way to increase productivity: imagine researching some topic in a Web browser on one screen while writing in your word processor on another. Not all Macs support multiple monitors, but almost every model that can handle multiple video cards can handle multiple displays. Also, some Macs that physically support multiple monitors do so only in video mirroring mode, where both screens display the same image rather than combining to create a single larger desktop. We’ve written extensively about multiple monitors in the past (see our "Multiple Monitors!" article series for details and advice), and the topic has come up frequently in TidBITS Talk.
Virtual desktops are similar to multiple monitors in that they enable you to have a larger desktop size. Unlike multiple monitors, however, the extended desktop isn’t displayed on a separate screen; instead, you can scroll or shift your primary screen(s) to bring additional desktop space into view. Some video cards enable virtual desktops through their driver software; other software-only system enhancements such as AWOL Software’s Virtual Desktop and Pierre-Luc Paour’s Virtual also offer virtual desktop capabilities, though neither has been updated recently (and Virtual’s author doesn’t recommend using it with Mac OS 9).
Adjusting Screen Geometry — This was our "trick" answer (although deductive logic is still legal in most countries, so you could have figured out that all the answers were correct once you realized that at least two of the others were correct). By adjusting screen geometry, we mean twiddling with the horizontal and vertical size and position controls on your display to reduce or eliminate the black border that surrounds your computer’s display. On many screens half an inch or more of black can be eliminated from the top, bottom and sides of the display, effectively increasing the display’s physical area.
Increasing the image size on your monitor to eliminate the black band has the immediate advantage of increasing the size (but not the number) of pixels, essentially making the existing desktop image appear larger and easier on the eyes. That in turn might make the next higher resolution (which does increase the number of pixels) more palatable, and since a higher resolution enables you to see more information at once, it would have the effect of increasing productivity.
This trick works only on CRT-based monitors, not on LCD-based displays, which use all their available pixels all the time. The reason it works is that the electron gun that paints pixels on the screen can be adjusted to light up the phosphors in the otherwise dark band around the edges of the screen. Now, if this is such a great tip, you might ask why the black band exists at all. The answer lies in the downside to increasing the size of the screen image – the necessary twiddling involved in increasing the size, repositioning the image, and eliminating distortion (where the edges aren’t parallel, or where they bend inward or outward) is likely to deform the image slightly. Will you notice? Perhaps, but unless you’re a graphics user who cares about the precision of an image’s dimensions, you’re unlikely to care. Personally, I feel the benefit of the increased image size well outweighs the disadvantage of the slightly distorted pixel dimensions.
Making the changes takes a few minutes of trial and error, potentially preceded by some consultation with your monitor’s manual. (For those with iMacs, the controls are all software-based and accessible through the Monitors control panel.) The important controls are generally labeled (with abbreviations being common) Horizontal Size and Vertical Size (or sometimes Zoom), along with Horizontal Position and Vertical Position. First, increase the horizontal size control to fill as much of your screen as you can. However, the image often isn’t exactly centered to begin with, so you generally need to fiddle with the horizontal position as well. Then repeat the process with the vertical size and position controls. After you’ve changed the size and position of the screen image, look at the edges of the screen. If they’re concave or convex, or not appropriately parallel, use the geometry controls (which can have a variety of names) to straighten the edges, rotate the entire image, and help make the various edges parallel.
Your monitor should remember the new settings, although I’ve seen them drift over time, so if you ever notice something that’s not quite right, tweak the screen geometry controls to bring it back to just the way you like it. And I encourage you to take this information – both the instructions on eliminating the unused black band and the bits about screen resolution, multiple monitors, and virtual desktops – and pass it on to less experienced users who can benefit from either a slightly larger screen image or the increased resolution it makes palatable.