|
|
WEB
ACTIVITIES: LIGHTS, CAMERA, ACTION!:
3D Photography and Anaglyphs
III. DO IT YOURSELF: Make an Anaglyph
You
can produce your own anaglyphs in a number of ways. Try one of these methods
and exchange with your Light Buddy.
Overview:
Methods which allow three-dimensional perception of a two-dimensional
object all require two slightly different images, with each eye seeing
only one of the two. This is accomplished by:
- photographing through two different colored filters and superimposing
the image
- viewing through two different colored filters (3D glasses)
These images must be viewed through 3D glasses, with one green lens and
one red lens. You can also do this activity with glasses and filters that
are cyan or blue. For this example, we will use green and red filters
and lenses.
In order to successfully superimpose the images, you must be very careful
in positioning the camera. A tripod (or some other support) is essential
in order to maintain the precise visual field in the camera lens.
If you are using slide film, you will photograph the image twice, displaced
slightly -- once through a green and once through a red filter. These
will be projected on a screen and viewed with 3D glasses.
If you have a camera which permits double exposures, you will be able
to photograph twice - once through one filter, then slightly offset through
the second. Both images will appear superimposed on your color print.
If you are using a digital camera, you will be able to photograph the
image once with each filter, then use software (such as PhotoShop ®
) to superimpose the images to view them with 3D glasses.
Materials/Equipment:
- Camera/film equipment:
- Camera and film for slides, or
- Camera which can take double exposures, and film for prints,
or
- A digital camera and software which will permit superimposing
images
- 3D glasses, or red and green filters . (You can make your own 3D
glasses from color filters; see Resources section.)
- Tripod
- Note for Digital Camera Users If you are using a digital camera,
you can produce anaglyphs without the filters using image processing
software. See one of the following URLs for step by step directions
and discussion on how to process the images using this software.
Tips on Photographing
- You may have better success photographing outdoor scenes which consist
of some objects very far away and some near.
- To achieve a good exposure, make sure your scene is very well-lit.
Attempting to produce indoor anaglyphs is much more challenging and
not the best place to begin.
Procedure
- Set up and take the first photograph. Place your camera on
a tripod in front of your scene. Carefully choose a marker as the center
of your scene which you will use to align the second photo. Place a
blue-green (cyan) filter over the lens and photograph the scene. (You
may have the best success if you actually use the lens from a pair of
the 3D glasses as the filter.)
- Take the second photographs. Carefully move the camera approximately
6.5 cm (2.5 inches) to the right. Center on the same mark, and place
the red filter over the lens to shoot the scene.
- Develop the film. Develop and process your film if you are
using film or slides.
- View the resulting image with 3D glasses. These will have the
blue/green (cyan) filter over the right eye and red filter over the
left. The three-dimensional image should "jump out" at you.
- If you used slide film, you will need two slide projectors to
project the images on a screen, taking care to align the marker
you used as your central point
- If you used a double-exposure camera and print film, you should
be able to view the print directly with 3D glasses
- If you used a digital camera, you will need to electronically
superimpose the images, placing them so that the central marker
is aligned on each; then they can be viewed with 3D glasses.
Try some other activities that explore anaglyphs and filters with your
students. Read on in IV. Do It with Your
Students.
I.
The Web Activity
II. The Science
III. Do It Yourself <
IV. Do It with Your Students
V. Resources
|