INSTRUCTIONAL TECHNOLOGY 3(2+1)

Lesson 26 : Projected Visual Aids

Slides

A slide is a transparent mounted picture which is projected by focusing light through it.

Slides of 35mm films mounted on individual card board frames are more common and are extensively used in extension programmes. Glass slides are generally used in cinema hall.

There are two types of slide projectors one is manual operated and cheap, in which every time the projected slide is taken out and a new slide is inserted in the slot and pushed by hand in position. The other one is automatic slide projectors in which large numbers of slides are serially inserted in the magazine slots before hand and are changed one by one at the time of projection by a remote control but produces good quality images and is extremely convenient for a slide show.

Slides are used in training programme, seminar, workshop, group meeting, campaign exhibition, T.V. etc.,

Advantages:

1. Attract attention and arouse interest of the audience.
2. Selected slides may help in motivating the audience.
3. Projection of slides may be synchronized with the talk.
4. A large image is possible
5. Large projected images can be made of small visuals
6. Images can be changed remotely, or automatically
7. Slides can be sorted, changed or substitute easily
8. Slides are relatively inexpensive to have processed

Disadvantages:

• For a clear image and bright color, you must darken the room.
• Slides are expensive if prepared commercially or if the art work, drawing, etc., is prepared especially for the slide
• Understanding the projected pictures requires ‘live’ narration
• The extension agent has to develop skill in taking photographs and projection of slides