Looking For a Monitor
By Howie Fenton
If you work on a computer most of the day then your choice of monitor may be just as important as your choice of computer or scanner. Why? Because your choice of monitor can influence your productivity, job satisfaction and possibly even your health.
What is the relationship between your monitor and your productivity? In some cases monitor size determines work efficiency and monitor input options determine flexibility. Anyone that worked on the original Macintosh computers, remembers those postage stamp size, 9" black and white screens and learned how frustrating and unproductive it was to zoom in and out of different views as well as mouse around using the scroll bars. When the 13" Apple color monitors became available it was immediately obvious the importance of color. And today if you're not working with at least a mid size color monitor you may be wasting valuable time.
What should you look for when considering a new monitor? The main specifications are compatibility, resolution, size, sharpness, cost and the possible health issues.
In the early days of desktop publishing making purchases for Mac monitors was easy. In those days the only monitors you could buy were fixed frequency Mac monitors. Monitors can display images at different pixel dimensions or resolutions. Most Mac monitors are single or fixed frequency monitors. The fixed resolutions for Mac monitors are 512 x 384 pixels on the Apple 12" monitors, 640 x 480 pixels for a 13" monitor, 832 x 624 pixels on a 16" monitor, and 1024 x 768 pixels on a 19" and 20" monitor. The latest 21" monitors can display at 1360 x 1024.
There is a another type of monitor, more popular with PC's, which is known as autosynch or multisynch monitors. These monitors can handle multiple synchronizing rates, or can automatically adjust the scan rates (synchronizing rates the number of times per second the screen is refreshed). Unlike the fixed frequency monitors these monitors work within a range of video rates. Multisynch monitors are more common in the DOS and Windows world, where the competing video standards make single frequency monitors less marketable.
Today there are multisynch monitors for Macs. If you're considering a multisych monitor, remember that it is important to choose a monitor that matches the frequencies sent from the built in video capabilities or matched to a specific video board. The spec's that describe these frequencies are the vertical scan rate.
The vertical scan rate, also known as the frame rate, indicates how often the screen is updated, the horizontal scan rate indicates how quickly individual lines are draw on the screen For example, the NEC multisynch 4FG uses a vertical scan rate of 55 to 90 hertz (cycles per second) and a horizontal scan rate of 27 to 57 kilohertz (thousands of cycles per second). The built in video signal from the Mac IIci, IIsi, LC, LC II or Quadra is 66.7 hertz vertically and 35 kilohertz horizontally. Therefore, this monitor range is within the range of the built-in video.
Many of the newer Macs have built-in monitor support. For example the Quadra 900 can run a 21" monitor at 8 bits, while the Quadra 950 supports a 21" monitor at the 16 bit resolution (with additional 1 Mb of VRAM). Unless you are performing color correction you might be surprised that only a small percentage of users can actually distinguish 16 bit from 24 bit color.
They main advantage of multisych monitors is flexibility. If you have both Macs and IBM-PC's in the same office you could mix and match monitors or you can use them on a variety of Mac's still utilizing different models internal monitor circuitry.
In general these are Super VGA monitors with a special DB-15 adapter that converts the signal to a 832 x 624 pixel signal. Some vendors, such as SONY require an extra adapter that they provide free. In fact almost any SuperVGA monitor can be adopted with an adapter. James Engineering (510 525-7350) sells an 832 x 624 adapter called the MacComp 16 for $25.
Monitors come in all shapes and sizes, most vary in size from 13" to 21". There are three general size categories: entry, midsize, and two page monitors. Entry level monitors are 13-14", midsize 15"-17" and two page monitors range from 19" - 21". In general the entry level monitors are those you buy when you buy your computer.
One of the confusing aspects of monitors is the actual viewable area, known as the active screen size. That's because some vendors use the diagonal size of the tube while others use the diagonal size of the viewing area. Viewable areas of two monitors of the same tube size can vary by 1 inch or more.
There is a relationship between the video signal, the monitor size and the sharpness of the characters. If you took the same video signal and viewed it in a smaller and larger monitor which would look sharper and would look larger? The smaller would be sharper at a smaller size and the larger monitor would have larger characters.
If you use the same resolution or number of pixels to drive a larger screen the characters will appear larger.
make a screen image the larger screen displays larger characters. For certain, nearly the same size monitors, larger characters are more legible. For example, under Windows at 1024 x 768 a 21" monitor is more legible than a 15" monitor because the character size is lrger. Increasing the resolution to 1280 x 1024 pixels, increases the number of characters that can be displayed but reduces the size of the type. Just because a specific 15" monitor can produce 1280 x 1024 pixel resolution does not mean that the text will be legible.
Clearly the most important attribute of any monitor is sharpness. Factors such as dot pitch, band width, and internal electronics contribute to a monitors sharpness. Bandwidth is the frequency with which the image is drawn on screen. Dot pitch is the distance between the centers of adjacent same-color dots. In general low dot pitch and high bandwidth will create a sharper images.
On difficulty however, if you try to compare specifications. If is difficult because different manufacturers use different specifications. For example, some measure dot pitch. However other manufacturers use different technologies to sharpen images. Sony Trinitron monitors arrange phosphors in rows of verical lines, whereas conventional displays arrange phosphors in red, green, blue triads to form dots.
Glare reduces contrast. Most monitor screens are treated to reduce glare. There are a number of antiglare treatments. Some such as etched screens and mesh filters result in a loss in sharpness and increased contrast. In comparison, coatings and darkened glass generally preserve sharpness.
Manufacturers have implemented anti-reflective coatings, display technologies and power consumption into monitors. Proprietary screen coatings can reduce reflected light by 50 or more.
Conventional curved monitors can use Invar shadow masks as a display technology. Invar is a more stable material than traditonal metal masks. Shadow masks are metal screens twith holes in them that focus the electron beams onto phosphors t. Trinatron monitors with vertical slots instead of holes.
Other factors that determine sharpess are the type of phosphors used and convergence factors. The type and amount of screen distortion can also affect the image. One of the important things to check with new monitors isthe sharpness at each corner.
Is bigger better
The majority of monitors in use today are the entry level units. According to Monitrak, a report published by Sanford Resources in San Jose California, 76% of the monitors bought in the first quarter of 1993 were 17" monitors. The 17" market made up only 2% of the total (something from Griffin Dix)
If your entry level monitor is starting to appear small you should consider a mid-size monitor. A 16" monitor provides 70% more pixels then a 13" monitor and the 17" monitors provide 45% to 60% more screen area then 14 inch monitors. In addition these mid-size monitors are less bulky and less expensive, then the 19-21" models. In the NEC product line the 21 inch MutiSynch 6FG is 22.4" deep and weighs 79 pounds. In contrast the 17 inch MultiSynch 5FG is 19.8 inches deep and weighs 56 pounds. Often cited as the most important reason to opt for a 17" monitor over the 2 page monitors is price. An average 21" monitor lists for between $2000 and $3000 while 17" monitors list for about half the price.
Another attractive feature about 17" monitors is higher resolution. On the PC for example 14" monitors run VGA well and SVGA fair. Most 17" monitors are well suited to SVGA and some can perform at 1280 by 1024.
If you average more than 6 hours/day in front of your computer and find yourself losing time scrolling and zooming in and out of different views then you should consider a two-page monitor. Some page layout programs and presentation software allow you to view two documents. If both files fit then on the screen then you can move information from one document to another quickly and efficiently. The ability to drag and drop information from one Quark document to another requires having both documents on the screen. If you customize slide presentations, presentation software such as Persuasion allows you to build new presentations by copying slides from one thumbnail view to another.
Many of the PostScript drawing programs have several floating palettes which, if utilized, increase productivity. Simply utilizing all the menus on Illustrator or Freehand and viewing the entire document requires a large monitor.
Experts say that opening and closing the same programs causes memory fragmentation. If you work on several programs during the day the most crash resistant way to work is to leave them all open until you shut down. If you want to search through a image database such as Fetch, utilize Photoshop or Illustrator for special effects and then insert the images into XPress it is more efficient to have them all open in different portions of your screen.
Clearly there are many ways in which larger monitors can help you work more efficiently. If you are considering a new monitor look at our gallery of award winning monitors on the next few pages.
After you have considered the myriad of factors in purchasing a monitor, you should consider one other factor: possible health issues. This is a controversial issue, so let's try to distinguish fact from allegations. Fact: monitors emit low frequency electric and magnetic fields.
Allegation: these emissions are associated with or result in health problems. Allegation: these health problems include miscarriages and cancer and CVS (computer vision syndrome). Allegation: 10 million people suffer from CVS which includes eyestrain, fatigue, blurred vision, double vision and headaches. Fact: there is no conclusive evidence to support any of these allegations.
Just The Facts
Monitors emit two classes of emissions ionizing and non-ionizing radiation. Ionizing radiation such as X-rays and ultraviolet rays are recognized health hazards and carcinogens. Some forms of monitor emissions are regulated through FCC rules. However, non-ionizing radiation, such as VLF (very low frequency) and ELF (extremely low frequency) occurs at lower frequencies and is not regulated.
The three accepted measurements of monitor emissions have been developed in Sweden. Two have been promoted by the Swedish Board for Measurement and Testing and are abbreviated MPR (its initials in Swedish)
The original MPR focused on alternating magnetic fields in frequencies from 1 to 4000 kilohertz which include the VLF frequencies from the horizontal scanning of monitors. MPR II extended the standard to electric and magnetic fields and decreased the reach to 5 hertz. MPR II includes vertical frequencies in the ELF band.
Another group, the Swedish Office Workers union, developed the TCO standard with is similar to the MPR II standard, but sets more stringent limits on low frequency fields. It requires measurements to be made at 30 cm (11.8) instead of MPR II's 50 cm (19.7")
The consensus of opinion is that the relationship between monitors and health issues is unproven. In some studies the motivation and objectivity of the testers have been suspicious. Studies done by the Electrical Power Research Institute claim that emissions poised no threat. But the methodology and motivation are questioned. There is anecdotal evidence that there is a higher incidence of miscarriage in women exposed to radiation. However the evidence does not prove cause and effect relationship.
Despite the lack of evidence several monitor companies including Apple and IBM and begun to introduce models that emit reduced levels of VLF and ELF. The companies are quick to say that the evidence is inconclusive but the fears are not. According to Rita Black, an IBM spokesperson "We would be naive not to acknowledge the concern that is out there. But we believe our VDT's including those already installed are safe to use."