Technology Learning Modules: Video Magnifiers
This learning module is focused on video magnifiers, sometimes called Closed Circuit Televisions (CCTV). The module consists of learning objectives, an introduction to video magnifiers, a video demonstration three types of video magnifers, an explanation of various uses of video magnifers, a summary and an assessment. To complete the learning module, read the entire webpage of text and watch the video. Then, respond to the assessment questions.
* Please note: If you are completing this module for a class, your instructor may ask that you respond to the assessment questions in a separate document and turn in your responses for a grade.
By completing this learning module, students will be able to:
- Define the term video magnifier,
- Name and describe three categories of video magnifiers,
- Uderstand the purpose for using video magnifiers,
and discuss the various types of settings found on video magnifiers,
and how one may adjust these setting to meet his or her individual
INTRODUCTION TO VIDEO MAGNIFIERS:
People with low vision rely on a variety of tools and strategies to help them access their environment. Probably most essential is their use of optical aids, such as magnification to assist with viewing objects both near and far away. In this segment, we will focus on the electronic optical aid known as the video magnifier.
A video magnifier uses a camera to project images that are transmitted to a monitor that displays the picture or text. These images can be adjusted for brightness, contrast, color scheme, and magnification. Many models of video magnifiers exist, ranging from portable hand-held devices to larger desktop fixtures. The three main categories of video magnifiers are stationary, portable, and a hybrid category that combines features from both stationary and portable video magnifiers, as described below.
Stationary video magnifiers typically contain a large video monitor, camera, and tray. An object such as a textbook is placed on the movable tray, which allows the user to easily slide the book in any direction. Changing the monitor’s settings is achieved by manipulating easy-to-access buttons or levers. Because of their larger design, stationary video magnifiers are usually permanent fixtures for use in the home, office, or classroom. They typically cost between $2500 and $3500, but can increase in price when adding HD features and compatibility with a computer.
Portable video magnifiers rely on the same video camera technology to magnify images, but at a greatly reduced size, weight, and cost. This makes it a convenient solution on the go when a stationary video magnifier is not available or practical. Simply place the portable device over the material to be enlarged and use the buttons to change parameters including magnification, color scheme, and freezing the monitor’s image. Popular models range in screen size from three to six inches and cost between $300 and $800.
Hybrid video magnifiers have the added feature of allowing the user to view distant objects such as a classroom whiteboard. This is achieved by rotating the camera from its traditional downward position to a forward facing position. The ability to shift the camera lens from viewing near objects to distance objects is particularly useful in classroom settings when a student must attend to the lecture notes being presented at the front of the room and textbook materials which are on his or her desk. Additional viewing options such as changing the magnification, contrast, and color schemes are easily adjusted by manipulating buttons on the camera or on a remote control. Hybrid video magnifiers range in price from $2500 to $3000.
Now, we’ll take a closer at three individuals who use video magnifiers to accomplish day to day tasks. We will explore the three types of video magnifiers, and how these individuals adjust the settings to meet their needs. We’ll begin with the stationary category.
ADDITIONAL USES OF THE VIDEO MAGNIFIER:
Video magnifiers can be used to accomplish a variety of day-to-day tasks, such as reading or viewing:
- Newspapers, magazines, and books,
- Recipes and cookbooks,
- Instruction manuals,
- Labels on various products,
- Photographs, and
- Phone books.
Additional tasks that can be accomplished using video magnifers may include:
- Threading a needle and hand stiching or sewing things,
- Drawing, painting, and doing craft projects,
- Building small models or objects,
- Grooming your finger nails or even painting them.
ADJUSTING THE SETTINGS:
Learning to adjust the settings, although simple, should be done with special attention to the needs of each individual who is visually impaired. Some individuals may prefer large magnification, while others may find the enhanced size to be more difficult to read, especially when reading connected text such as long paragraphs found in books. One trick to adjusting the magnification is to locate the object or text in the center of the screen using a reduced magnification and place a finger on the exact target. Then, using the finger as a locator, slowly increase the magnification until it is adjusted to the individuals’ liking. As one engages in the task, the magnification may need adjusting, and the individual should learn to change the magnification as needed while maintaining the specific location of the image on the screen. Likewise, some individuals may prefer to adjust the color scheme and view the text using reverse polarization in which light colored text (e.g. white or yellow text) is presented against a dark background (e.g. black or dark blue background). The use of reverse polarization may be particularly helpful for individuals who find bright light or glare uncomfortable. The preferred settings may change depending on the task, size of the print, and purpose. Therefore, individuals who use video magnifiers should become adept at independently adjusting these settings to meet their visual needs, given a variety of tasks and materials.
In this module, three categories of video magnifiers were introduced:
We saw a video demonstration of three individuals, each who used one of the devices. We also saw a demonstration of how and when these individuals adjusted specific settings to help them see the materials better. Lastly, we learned about the day-to-day tasks for which an individual may choose to use a video magnifer.
ADD ASSESSMENT HERE --
*NOTE: This module and other learning modules were developed from by the OSEP Federal Grant Competition: Combined Priority for Personnel Development Grant # H325K110410.
regarding the credential program in Visual Impairment and Blindness at
CSULA, please contact Dr.
Kamei-Hannan, the program coordinator, at
323-343-6297 or firstname.lastname@example.org.