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   הזמנת אישור לימודים וציונים



THE OVERHEAD PROJECTOR

BASIC RULES
OPERATING THE OVERHEAD PROJECTOR
CREATING AND PRINTING TRANSPARANCIES

POINTERS FOR EFFICIENT USE OF THE OVERHEAD PROJECTOR

There are a few simple rules to follow to efficiently use the overhead projector.

  1. The letters on the transparency should be "large enough".
    a. Keep your letters large enough that the person farthest from the screen can easily read it.
    • Usually do not use fancy fonts.
    • Lines, for graphs, charts, etc., should be wide (2 pixels).
    • Set the page format (page setup) in landscape - width not length.
    • Set margins at
    b. Do not copy text from a book or written page and then directly project it. Either:
    • Type out much larger letters (font size), and divide the page into numerous pages; or alternatively,
    • Enlarge the page through photocopy enlargement.
  2. The transparency should not be congested with too much information.
    Put only concise, pertinent information on the transparency. Your verbal explanation should go into depth on what is headlined on your projection

  3. Show only the information needed at the time.
    Cover up the other information, since the receiver's eyes will be attracted to all the projected information and he/she will concentrate less on what is being said. All concentration should be on the present discussion, not the past or future (projected).
    • Transparencies can be placed one on top of another to add additional information.
    • " Information can be "revealed" by uncovering a subsequent portion of the slide which had been exposed.


  4. 4. Turn off the projector, or cover the information, when it is not being used.
    Similarly, turn off the projector when not using it. As long as it is on, the receiver's eyes will automatically be attracted to it and not necessarily paying full attention to the presentation.

    Some projectors use bulbs that take time to relight. In such a case, do not turn the machine off. Cover the lighted area with an opaque object such as a piece of paper.

  5. Generally, point on the transparency, not on the projection.
    Try to keep away from pointing to the projection. One of the positive features of the overhead projector is that it allows for a continuous frontal presentation. Point on the transparency with a pen or similar object with a point, laying the object flat on the projector's surface. Otherwise, this pointing object would became distractingly large with a shadow being cast on the projection.

    It is good practice to mount transparencies on frames.
    • They handle much easier.
    • On the machine, they can be mounted one on top of the other, with easy exact positioning.
    • Notes can be written on the frame to aid the presenter.


OPERATING THE OVERHEAD PROJECTOR

There are three basic operating functions common to all overhead projectors, and three additional functions found in many.
  1. Power Switch: turns the machine on and off.

  2. Focus: focuses the projected picture. On most table models, it is usually done via the knob that raises and lowers the top part of the machine. On portable models, the focus is usually a knob on the top part of the projector, or ring under the lens.

  3. Projection direction: On most modern projectors, the flap containing the mirror on the upper part of the machine directs the bearing of the projection. On older projectors the entire top section rotates with the loosening of a knob on that part of the machine.

  4. Bulb Changer: Many overhead projectors contain two bulbs, in order that if one burns out in the middle of a presentation, the second can easily replace it. On table models, a lever on the main body of the projector should be moved all the way to the opposite side. On portable units, this lever or knob is usually on the top part.
    IMPORTANT: If this lever is not all the way to one side or the other, most projectors will not light at all, causing the user to believe the machine is broken.

  5. Keystone Corrector: Keystoning occurs when the projection direction is not straight, causing the picture to be oblong rather than rectangular. Some projectors have a knob that corrects, or partially compensates, for this effect.

  6. Brighter Projection: Some projectors have a switch that allows for getting slightly brighter light. In the lesser light mode, the bulb, theoretically, lasts longer.

CREATING AND PRINTING TRANSPARANCIES

Transparencies are produced in three ways: free-hand, copying and computer.
  1. Free-hand
    It is possible to write or draw directly on a transparency, even while is being projected. Specific transparency film for free-hand writing and special markers should be used. This will allow for clear projection of what is written and minimal amount of smearing. The writing could be later erased with alcohol or "spirit".

  2. Copying
    Today, it is very easy to copy information from a plain piece of paper or book onto a transparency on a normal photocopying machine. The paper or book is photocopied in the normal manner while a specific transparency film for photocopiers is used instead of a blank sheet of paper.

  3. Computer
    Any work done on computer can be printed directly onto a transparency (without having to make a normal paper printout and then photocopy onto a transparency). In the printer, substitute the transparency film for the blank sheet of paper to be copy.

NOTE: Each method of transparency production (free-hand, photocopying) and each type of printer (jet-ink, laser) have their own specific types of transparencies, and one function will not work well with the other's transparency. While a photocopy transparency works with a laser printer, there is a good possibility of the printer jamming after a few copies.

Ó 2005 Steven F. Rosenberg