from Educators' eZine
I stood in front of the classroom and turned on the power to the overhead transparency projector. Placing a paper printout on the projector, I was met with a projected shadow of the paper and advice from a polite student at Austin High School; "Mr. Frisk, you have to use a transparency with the projector. Paper will not work." Twenty-three years earlier, I had graduated from this school and had just returned as a non-certified substitute teacher, in front of a classroom for the first time. I had never appreciated the stand-alone transparency projectors, desiring something that would show an image printed on paper. A generation later, I discovered little had changed in the classroom, with the exception of white boards replacing black boards, a computer on the teacher's desk, and resemblances of my old classmates in the faces of their children I was now privileged to instruct. A few years later, on my first night in graduate school, I found the projector I desired.
A Better Way to Present
The document camera, commonly known as a video visualizer/presenter or Elmo, a popular brand, is a modern replacement for the stand-alone overhead transparency projector, a device first developed to train soldiers during WWII (Crystal, 2008). Document camera technology consists of a video camera mounted on a stand with an illuminated display platform under the camera lens. Material is placed on the platform and projected through an overhead-mounted projector or by way of a television set. The document camera can display almost anything placed under its lens, including transparencies, opaque materials such as black and white or colored paper printouts and 3D objects. There is no waiting in line at the copier to create a transparency minutes before class begins, and no standing in front of the class, getting in the way, while presenting material. A teacher can stand at the back of the classroom or off to one side and display material via an S-Video cable attached to the camera and leading through the ceiling to a projector or TV. Any printout or anything in a book can be displayed by setting it beneath the camera lens, and transparencies can be viewed by turning on a base light. The learning curve with this technology is short, often measured in minutes.
Document Camera Advantages
A dozen document camera advantages:
- Display paper printouts, slides and transparencies
- Display text and/or photos from a book
- Display three-dimensional objects
- Display and save "live" images
- Display in color or B & W
- Zoom in and out capability
- Long-lasting fluorescent lighting
- Ease and spontaneity of operation
- Students pay better attention
- Students can show off their work
- Useful across disciplines
- Does not require a computer or networking
- Far greater cost than stand-alone transparency projectors
- Require a projection unit or TV set
- Lack of familiarity among teachers and school administrators
