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1 Physical Science PHYSICS () S C I E N C E PHENAKISTOSCOPE This Enrichment4You e-guide provides a brief overview of s. In this e-guide you will: Physical Science (Physics) O P T I C S *Learn Basic Information About the Development & Use of s. *Make a. ENRICHMENT4YOU Published by Henrich Incorporated Copyright 2005 All rights reserved. No part of this publication may be reproduced, stored in a retrieval system or transmitted in any form by any means, electronic, mechanical, photocopying or otherwise, without first obtaining the written permission of the copyright owner.

2 Physical Science PHYSICS () INTRODUCTION The purpose of this Enrichment4You e-guide is to provide inspiration, ideas and techniques for creating a tabletop phenakistoscope. In this e-guide you will read a brief overview about phenakistoscopes and follow a step-by-step presentation with photographs on how to make a tabletop phenakistoscope. Do not feel limited in the selection of suggested materials. Your finished phenakistoscope will incorporate scientific elements from these historic optic toys. You may even use the model to create larger and smaller versions of a phenakistoscope. Have fun and be creative. TABLE OF CONTENTS 1. Brief overview of s - Pages Make a Tabletop - Pages Physical Science (Physics)

3 Physical Science PHYSICS () Did You Know??? A phenakistoscope is a toy that gets its name from the Greek words meaning to trick. PHENAKISTOSCOPE A Brief Overview s were originally called spindle viewer. Invented by Joseph Plateau and his sons, a Belgian physicist in 1832, the phenakistoscope creates an illusion of movement through persistent motion. Joseph Plateau extended the idea of persistence of motion first understood by Euclid, a Greek mathematician and through experiments conducted by Issac Newton. The original phenakistoscope used circular discs mounted to the same axis that spun in the same direction. One disk had small, equal slots cut out around the exterior with the back side painted black. The other disk had a series of small drawings showing a sequence of images with slight changes occurring between each image that were positioned next to the slots of the first disk. Most phenakistoscope discs featured 6-12 sequential images with an equal number of slots. These images were placed next to the slots cut in the disk. Common image themes included showing a person or animal walking, tossing a ball, or people dancing. The sequence of the images were designed to have a smooth flow from beginning to end. Physical Science (Physics) 1

4 Physical Science PHYSICS () Did You Know??? The phenakistoscope is also called the Fantascope, Phantamascope, Magic Disc or Kaleidorama. The phenakistoscope images were twirled in front of a mirror. The observer looked at the mirror through the slots of the turning disks from the back. The reflection of the images in the mirror made the images look as if they were moving. This was one of the first forms of animation. The concept of persistent vision demonstrates the connection between how the human brain perceives light. Light is not perceived by the human brain right away. Scientists have observed that it takes about a tenth of a second after a light is turned on for a person to recognize the light. In the same way, an image persists about a tenth of a second after a light is turned off. The phenakistoscope demonstrated this principal. As the disks revolve, and the images are viewed through the regular slots around the outside, the human eye and brain see the images quickly. If the images are drawn in such a way as to show small movements, and since the eye and brain can only process the information within a tenth of a second, one image fades as the next one on the disk is viewed - the result is that the brain sees the images moving. In movies, there are approximately 24 frames of film every second. Each frame shows a slight change in the image so that when they are shown together, the brain sees the images as a moving scene. Physical Science (Physics) 2

5 Physical Science PHYSICS () Some image subjects for phenakistoscope disks. frames can include any of the following and be very effective in showing movement. Bouncing Ball - the ball moves up and down over 6 to 12 frames showing a path of movement. Walking - Whether animal or human showing the repeated movement of the figure over 12 frames is an easy and effective motion demonstration. Metamorphosis - Show how an insect or animal changes from one stage to another such as a caterpillar to a butterfly, tadpole to a frog or an egg into a flying bird are excellent subjects for a phenakistoscope. Shape Change - an image morphs into another shape. For example, a square changes into a circle, a rectangle changes into a diamond are easy and fun subjects to consider. Other Events - an erupting volcano, a smiling face, a jet flying, the sun rising and setting are good subjects for animation. HELPFUL HINT: Physical Science (Physics) 3 Look at How to books on drawing simple shapes for inspiration. Many show how to draw an image from start to finish. If there are less or more than 12 steps, make small changes in the images to adjust or add to the required number of frames.

6 Physical Science PHYSICS () Make a c2005 Henrich Inc. s are fun, easy and a great way to observe movement. Movement is sequential. The principle of persistence of vision maintains that a visual image remains in the brain for a brief period after the images is no longer being viewed. Optical toys demonstrated this principal with great success. They were the first efforts at animation and motion pictures. By breaking down the steps or sequence from beginning to end, you will be able to create images that look as if they are moving when viewed through the phenakistoscope. Physical Science (Physics) 4 MATERIALS *White & black cardstock paper *Copy machine *Drawing paper *Skewer *Mirror *Pen, pencil art supplies, *Coat hanger wire *Small piece of wood *Metal cutters