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Adapting Video for VI Learners

Effects of visual impairment

Problems in seeing details

What is meant by seeing details?

We mean the ability to see small objects, text, or drawings. People need relatively good visual acuity or sharpness of vision to do this and good contrast and the ability to see it are also important. These abilities depend on having functioning central vision.

What effect does impairment of vision for detail produce?

It can cause major problems for the person who is unable to see detail. Much of our daily living activities and learning tasks take detailed vision for granted. Reading, working with pictures, fine technical and craft work, and use of video and TV all suffer.

Poor vision for close work

Students are expected to read a vast amount of material and this poses access problems for people who have impaired or non-existent visual acuity. Each day we come across all kinds of labels, diagrams and information in textual format. There are several aspects to the problem. The most obvious is that of overlooking information completely. To this should be added the extra time involved in reading, and the attendant issue of fatigue. Working with multiple sources exacerbates all this: finding your place again having left a book to look up a cross reference takes time and energy. Similar difficulties face people who have to work with fine manual tasks - tools are hard to see, the work area is blurred, and progress is slow.

>What can ease this problem?

Bringing the object or text closer to one's eyes, wearing glasses, using magnification, enlarging material, having material read out or transcribed into braille or raised diagrams or graphics are all ways to help with this problem. Each brings secondary problems such as limits to the field of view, extra work and time in switching between visual aids, and extra cost of specialised materials preparation.

Poor visual acuity for distance.

This can prove just as problematic as not being able to see near objects, especially because of the risk of missing important details at distance from us. The further from you the object is, the more likely that you can overlook it if your visual acuity is low. Street signs, bus numbers, adverts on hoardings, social signs such as "exit" or "Ladies", information on notice boards, slides, overhead projection slides: all of these convey important, vital or just plain interesting information but may be missed. In the picture below, what is lost is the teacher's facial expression and with it many communicative cues.

Seeing distant details(D)


What can ease this problem?

Much effort goes into mobility training, part of which involves strategies for locating and reading material at a distance. Asking a companion or using a telescopic aid are ways of getting round this problem. Some of these strategies will also be useful for video work.

How does this affect viewing video screens?

A video screen can be either relatively close to the viewer (as with a computer monitor) or in the middle distance. Which aids and techniques to use will depend on its distance, and the type and purpose of the video - whether there will be a great deal of text or detail within the material.

What would improve screen access?

If you have problems with details, try some of the following:

  • Alter your position with respect to the monitor to suit the material and your visual ability. Move back if the programme demands you get the 'big picture': sit closer to the monitor/screen or ask for a larger monitor if there is a lot of detail.
  • alter the contrast and brightness on the monitor controls:
  • use the freeze frame to give yourself time;
  • listen carefully to the commentary or audio description then view the problem frames again;
  • use a low vision aid to help magnification or to cut down glare if this is a problem.

What names of eye conditions should I watch out for?

All those with loss or reduction of central vision for example:

  • myopia or short sight
  • uncorrected long sight
  • presence of nystagmus
  • macular degeneration
  • poor contrast sensitivity