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Web Posted on: November 19, 1998


EVALUATING AND SELECTING A WINDOWS-BASED SCREEN MAGNIFICATION SYSTEM

Mark M. Uslan
Manager, Technical Evaluation Services
American Foundation for the Blind
11 Penn Plaza, Suite 300
NY, NY 10001
Tel. (212) 502-7638
email: muslan@afb.net

Joseph C. Su
Intern from the Cooper Union for the Advancement of Science and Art
American Foundation for the Blind
11 Penn Plaza, Suite 300
NY, NY 10001
Tel. (212) 502-7645
email: jsu@afb.net

Bradley Schnell
National Program Associate Technology/Rehabilitation
American Foundation for the Blind
401 N. Michigan Ave., Suite 308
Chicago, IL 60611
Tel. (312) 245-9961
email: brad@afb.net  

The objective of this presentation is to provide the comparative information necessary for consumers and professionals to be able to make intelligent purchasing decisions.

The American Foundation for the Blind's Product Evaluation Lab has published a series of objective evaluations of screen magnification products for Windows 95. Among the products evaluated were four screen magnification programs: Magnum Deluxe by Artic Technologies and LP Windows by Visionware (Uslan and Su, 1997), ZoomText Xtra by AI Squared (Su and Uslan, 1998a), and Supernova by Dolphin Computer Access (Su, Uslan, and Schnell, 1999). Also evaluated was Vista PCI by TeleSensory (Su, 1998), a hardware-based screen magnification system, and the Versatile Image Processor (VIP) by J. Bliss Associates, a system that uses a scanner and employs its own screen magnification program/word processor (Su and Uslan, 1998b).

What is the philosophy behind our approach to evaluations? We use an objective approach, trying out the product to see if it does what the manufacturer says it is supposed to do, and whenever possible, making comparisons from among competing products on the market. Periodically we use our database of user's of technology, (AFB's Careers and Technology Information Bank) to contact users for their reactions -- we hope to do this more in upcoming evaluations.

A screen magnification program is software loaded into a computer's memory that will magnify the text and graphics that appear in most common applications. Since screen magnification programs cost from $400-$600 (and the hardware system costs over $2,000), the question must be asked: Is a screen magnification program needed? Beyond the question of cost, this question is also important because of appropriateness. Is screen magnification software needed for people whose visual impairment is not severe, that is they do not need a great deal of magnification or other screen enhancements? This question is equally important for people at the other end of the spectrum, those who are severely visually impaired to the point where screen magnification may not be as efficient as speech output.

Consider the problem of magnified material going off the screen. A typical text based screen consists of 25 lines of text, with 80 characters per line. By comparison, at 4x magnification, only 6 lines and 20 characters per line fit on the screen, and at 8x, only 3 lines with 10 characters per line fit on the screen. A possible alternative to paying $600 for a screen magnification program, is a larger monitor. Replacing a 12" monitor with an 18" one increases the size of on-screen print by 50% and provides the full 25 lines of text, with 80 characters per line. A large monitor may also be helpful when using screen magnification-- if it allows for lowering the magnification setting used, more will fit on the screen. While large monitors are also expensive, they may reduce the frustration of material going off the screen. A large monitor may be worth the added expense.

Using a large monitor is one alternative solution. Other solutions may be found in Windows itself and still others may be addressed by screen magnification shareware. For the sake of argument let's say a large monitor, adjusting Windows, and experimenting with shareware does not give you enough screen enhancement. You are prepared to spend $600. The next step should be to try-out the different programs. Manufacturers give out demonstration disks, and they often can be downloaded from their websites. Trying out a screen magnification product is the best way to determine if it meets your needs -- the programs are similar enough so that you can quickly get a good idea if a screen magnification program is necessary, and you can get to know the features of each of the programs so you can chose the one you like the best. Trying out screen magnification programs can also help you make a decision to rule out its use or to assess how you will use the program -- for instance using a demonstration disk is a good way to determine that you really can't benefit from the screen magnification program and that what you really need is a synthetic speech program or that you need the screen magnification program to work in conjunction with speech.

To determine the most appropriate solution, we have identified 5 screen access problems that need to be addressed to a varying degree, depending on the needs of the individual. They include insufficient magnification, setting color and contrast, ease of use, locating items on the screen, and using synthetic speech. Some of aspects of these problems can only be handled by screen magnification programs but others may be efficiently dealt with by configuring the windows environment or using shareware.

In the remainder of this session we will go over how the 5 screen access problems are handled by Windows 95 and Windows 98, shareware, and each of the 5 screen magnification products we have evaluated.


References

Uslan, M.M. and Su, J.C., 1997. A review of two screen magnification programs for Windows 95: Magnum 95 and LP-Windows. Journal of Visual Impairment and Blindness (JVIB), Vol. 91, No. 5, pp 9-12.

Su, J.C., 1998. A review of TeleSensory's Vista PCI screen magnification system. Journal of Visual Impairment and Blindness (JVIB), Vol.92, No. 10, pp 705-710.

Su, J.C. and Uslan, M.M., 1998a. A review of ZoomText Xtra screen magnification program for Windows 95. Journal of Visual Impairment and Blindness (JVIB), Vol. 92, No. 2, pp 116-119.

Su, J.C. and Uslan, M.M., 1998b. A review of the Versatile Image Processor for persons with low vision. Journal of Visual Impairment and Blindness (JVIB), Vol. 92, No. 6, pp 388-392.

Su, J.C., Uslan, M.M., and Schnell, B., 1999. A review of Supernova screen magnification program for Windows 95. Journal of Visual Impairment and Blindness (JVIB), In Press.