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Adapting Video for VI Learners

Making the OHP and other teaching aids visible

General support

Students' ability to see teaching aids will vary widely. While blind students will have no access to any visual aid, some visually impaired students may be able to read overhead projector or slide notes with either a monocular, binocular or telescopic magnifier. The best 'catch-all' solution is for the teacher to have prepared copies of the acetates or slides in the students' preferred format e.g. Braille, large print, normal print, or raised diagram. If there hasn't been time or an additional slide is introduced, then it is important that the teacher reads out what is on the screen. This is sometimes hard to remember, especially if there is only one student with visual impairment in the class, but it is a matter of courtesy to that student.

Students, if you have teachers who forget to do this, have a word with them or your support teacher about it. If you feel sufficiently assertive, just ask on the spot "What's on the slide?"

Handouts are another standby of teachers and lecturers. A student with visual impairment should never be expected to share or look on with other students. An individual copy in the appropriate format should be provided.

Positioning and content design

As with locating monitors and TV screens, finding a good position with respect to OHP's and other aids depends on understanding students' needs and these will differ person to person.

Where students suffer from Visual field defects, positioning decisions need to take into account a wide range of issues. We summarise them here.

Where students have moderate problems seeing details, they need to be positioned square on and near to the screen. You can also help with good OHP design. Large print in 'bold' with a limited amount of information on each acetate helps the information to be read more easily. Avoid using too many colours, and choose tones which are in sharp contrast with the background colour of the acetate. Make sure that the OHP is clean!

If students have severe problems seeing details it may be better not to rely on the OHP at all. Where it cannot be assumed that the student will be able to see diagrams or read text from them as quickly as their fully sighted peers, appropraitely printed copies of the acetates might be more appropriate. If this is not possible, the content needs to be read out and diagrams explained.

There needs to be strong colour contrast on video and OHP acetates, especially for those students with colour perception problems or any central retinal condition. Note that when colour is used to highlight some video feature, or colour codes are used on the OHP, these may not be apparent to students: teachers need to reinforce them with careful explanation and questioning to check for understanding.

Students with narrow visual fields need to be positioned centrally. They will find it difficult to locate, read and scan information quickly - diagrams will be potentially difficult. Previews will be especially useful, so try to provide hard copies of acetates or even tape recordings before the sessions. This kind of pre-organisational material will also help students who have trouble seeing moving images.

Some students cannot change focus quickly (or in certain cases, at all). They will have no major difficulty if they just have to concentrate on the monitor or OHP screen. Problems will occur if the student is required to alternate between the teaching aid and a text or a worksheet. The student will be slow at doing this and may need to switch to different spectacles or low vision devices. If copies of transparencies are made available before the session, then these can be co-located with the other texts on the students desk, where no focus shift or change of visual aid is needed to see both notes and OHP materials.

Many of the design guidelines we suggest for production of new video and multimedia apply to making OHP transparencies and slides. These include avoiding the use of continual upper case, and advocate use of a 'bold' font to help to produce the maximum contrast between font and background. Some sans-serif fonts are easier to read than others (Helvetica is pretty good). Following these will help people who have contrast sensitivity problems. and provide handouts where ever possible.