PROJECTION SYSTEMS

PROJECTION SYSTEMS

Module 4

FILMSTRIP PROJECTOR

It is a device used to view a filmstrip. The term filmstrip refers to a roll of 35mm transparent film containing a series of related still pictures shown one at a time.

Until the 1960s, most filmstrips do not have an audio accompaniment, with only narrative information printed at the bottom of each frame. Since then, there has been a growing trend on having recorded sounds to accompany the filmstrip.

FILMSTRIP PROJECTOR

The audio used to be played on a separate player while the filmstrip is being shown but later on, players were built into the projector. However, because of the latest projectors available, filmstrip projectors are rarely found in classrooms today.

FILMSTRIP PROJECTOR

Advantages (Heinich, R., Molenda, M., & Russell, D., 1993).• It provides visual stimulation and motivation to the learner.• Filmstrips are easy to store.• Compared to slides, the filmstrips fixed sequence of the

frames ensures the presentation to be in order, without fear of having any of the pictures out of sequence or upside down.

• Pace of viewing can be controlled by the user.• It lends themselves well to independent study.

FILMSTRIP PROJECTOR

Limitations• The permanent sequence of the images makes

it impossible to alter its sequence without destroying the filmstrip.

• Sprocket holes get damaged or torn if filmstrip is constantly used or not threaded properly.

FILMSTRIP PROJECTOR

SLIDE PROJECTOR

It is a device used to view photographic slides. The term slide refers to a small format photographic transparency individually mounted for one-at-a-time projection (Heinich, R., Molenda, M., & Russell, D., 1993).

Slides are made by taking pictures with a slide film, processed, and then mounted in 2 by 2 –inch mounts. Because of the complex nature of this projector, its price is quite high that it is rarely found in classrooms today.

SLIDE PROJECTOR

Advantages (Heinich, R., Molenda, M., & Russell, D., 1993).

• Amateurs are now able to produce their own slides because photographic equipment has become simplified.

• Compared to filmstrips, slides are more flexible because they can be arranged and rearranged into different sequences.

SLIDE PROJECTOR

• Automatic projectors can hold sets of slides in trays and feed them in sequence. There are even projectors with remote control and timer.

• Slides can be integrated into individualized instruction program.

• Audio may accompany the slide show.

SLIDE PROJECTOR

Limitations• Slides can become easily disorganized.• Jamming of slides in the slide-changing mechanism.• Dust or fingerprints may accumulate on the slide if

not handled and stored properly.• Not effective in a fully-lighted room.• Since the room needs to be darkened during the

presentation, there is no face to face contact with the learners.

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SLIDE PROJECTOR

OVERHEAD PROJECTOR

It is a box with a large “stage” on the top surface. A lamp from inside the box is condensed by a special type of lens and passes through the transparency that is placed on the “stage”. A transparency may be composed of photographic film, clear acetate, or any transparent material capable of being imprinted with an image by means of chemical, heat process or direct drawing method.

OVERHEAD PROJECTOR

Practices and Reminders to Teachers When Handling and Using an OHP

1. Position the projector at least 2-3 meters from the screen.

2. Avoid projecting on a glossy surface.3. Check if the lenses and glass plate are clean.4. Place the transparency on the stage as you

would normally view it.

OVERHEAD PROJECTOR

5. Do necessary adjustments with the head assembly and focusing knob in order to ensure that the projection can be read by your learners who are seated at the farthest part of the room.

6. Make sure that your learners can see what you are projecting. Do not stand in front of the screen. Stand on the side of the projector where the on/off switch is located.

Practices and Reminders to Teachers When Handling and Using an OHP

7. Since your learners attention is divided between you and what is being projected, speak with more volume than you normally use.

8. Look at either your class or your transparency and NOT at the screen. An exception is when you are using a laser pointer.

9. Place the transparency on the glass plate before turning on the projector. Turn it off before removing the transparency.

10. Use dim lights.

Practices and Reminders to Teachers When Handling and Using an OHP

11. When using an OHP pointer, point it to the transparency itself and not on the screen. You may also rest the pointer on the text.

12. Gradually expose the contents of your transparencies through masking.

13. Use the OHP like a chalkboard if some materials have to be drawn or written.

14. Turn off the OHP when you are not using it during discussions.15. Make sure that the lamp has cooled before moving the

projector.16. Carry the OHP by its body and not by its post and head

assembly.

Practices and Reminders to Teachers When Handling and Using an OHP

Preparing Transparencies1. Print horizontally on the transparency.2. Use a large text size.3. Use standard fonts.4. Color of the text should be black. Use red

sparingly.5. Do not overload your transparency. Use the 66

rule – 6 lines per page and 6 words per line.

OVERHEAD PROJECTOR

6. Use topical outlines and NOT sentences.7. Do not reproduce a typewritten page or a page from a

book.8. Write notes on the frame of your transparency.9. Vary your presentation with the use of overlays (for

complex topics that needs to be explained step-by-step by flipping on a series of overlay one at a time that add additional features to a diagram or illustration), masking (strips of paper cover the transparency and content is shown one at a time), silhouettes (any opaque object), and cut-outs.

Preparing Transparencies

Ways in Creating Overhead Transparencies1. Direct Drawing Method A method wherein content is drawn or written directly on the transparency using a marking pen.

2. Thermal Film ProcessA master is prepared on an ordinary paper using heat-absorbing material such as India ink, ordinary lead pencil, or any substance containing carbon. The image on the master is then “burned into” (with infrared light) a specially treated acetate film.

OVERHEAD PROJECTOR

3. Electrostatic Film Process (Xerography)Transparencies are prepared using plain paper copying machines. A master is prepared on plain paper and then photocopied. Black and white, as well as colored transparencies (for some machine models only) can be produced using this method.

4. Computer-GeneratedTransparencies are prepared with the use of computers and then printed on an inkjet or laser printer.

Ways in Creating Overhead Transparencies

Steps in Preparing an Overlay Transparency 1. Prepare a sketch of the content.2. Decide which part of the sketch will be the base

and which will be the overlays.3. For each separate part, prepare a master

drawing.4. To make sure that the base and the overlays

align properly, mark two corners of each master.

OVERHEAD PROJECTOR

Steps in Preparing an Overlay Transparency

5. Prepare transparency from each master.6. Prepare the frame. It can be made out of a

folder or an illustration board.

7. Mount the transparencies on the prepared frame. The base will be placed under the frame while the overlays are placed on the top of the frame. Before taping the transparency, make sure that the transparencies are properly aligned – use the two corners of each master that you marked for proper alignment.

Steps in Preparing an Overlay Transparency

Advantages• It is simple to operate.• The rate of presentation can be controlled by the

teacher.• It is usually placed in front of the classroom, therefore

the teacher can still face his / her students.• Transparencies can be prepared through a variety of

simple, inexpensive methods.• It can be used in large groups.• It is effective in a well-lighted room.

OVERHEAD PROJECTOR

Limitations• It requires electricity and special equipment.• OHPs are heavy and bulky to transport.• Framed transparencies are bulky and difficult

to store.• It is instructor dependent.• It requires preparation since nontransparent

materials cannot be projected.

OVERHEAD PROJECTOR

OPAQUE PROJECTOR

This is a device that has the capacity to display opaque materials on a screen. The projector works with a very strong incandescent light which is reflected on a mirror that aims the light beam through a series of lenses onto a screen.

With this kind of projector, it is possible to have colors projected, small objects magnified so they can be viewed by a group and valuable prints or pictures viewed with minimum damage.

OPAQUE PROJECTOR

On the other hand, its limitations are the following: opaque projectors are heavy and bulky, the room usually needs to be very dark, heat from the projector can damage the materials being projected and opaque projectors are expensive.

OPAQUE PROJECTOR

LCD (Liquid Crystal Display) PROJECTOR

This is a type of projector that can display video, images, or computer data on a screen or any flat surface. For this projector to work, it should be connected to a computer. Slides for this kind of projector are also easy to prepare because of the presentation tools that are readily available.

Since its slides are stored as files in the computer, storage is not a problem. With this kind of projector, it is possible to show motion or have accompanying sounds. The downside of this kind of media is that for it to run, it needs electricity and computer. Other projectors also have poor contrast, some colors are distorted, and the room needs to be dimmed so that the projection can be seen.

LCD (Liquid Crystal Display) PROJECTOR