Slide Shows Then and Now, Part 2

Get the projector and screen - the slides are ready.

In Part One I presented the idea of a digital slide show. Computer files and devices such as digital cameras and scanners are 21st century complements to analog (traditional 35mm cameras and slides). The digital devices are complements inasmuch they expand the ability to capture, store, manipulate, and present images.

Present images - that's next! Let's take a brief look at screens and mechanical devices for projecting images.

Projectors used to view analog slides are mechanical devices with hot high intensity lamps as the light source used to project an image. A slide tray is the storage device from which a projector retrieves images from. Since the tray holds a limited number of slides - maybe 40, 80, or 140 slides - it must be removed and replaced during presentations of several hundred slides. A tray is inserted and slides are shown sequentially.

To view a slide on a wall, the light from the projector would be shown through the slide and focused onto a wall or screen. The size of image desired dictates the projector's distance from the screen. Many people can view the image on the screen.

Or you can use a handheld viewer to view a single slide using ambient light or a bulb (not of high intensity) that shines through the slide.

Slide shows - at least the ones in my family - more often than not were held at night, because it was easier to get a room dark. In other words, it was easier to create an environment with the best conditions to project an image onto a and see the results. The colors displayed could be in the billions, limited only by the condition of the slide, lamp intensity, ambient lighting, and condition of the screen. Bottom line is that you would have to pull together the equipment (generally stored in a closet), one or more slide trays, and plug in and turn on the projector to project an image onto a screen or a nice clean wall.

How does this compare to projecting and displaying digital imaging?

Projectors used to view digital images are either portable or desktop computers with a monitor of some sort attached to view images. Discs (either hard, floppy, CD, DVD, or Zip) are storage devices from which to retrieve images. There are different applications that can be used to view slides, with choices to display images of different sizes, selecting a transition effect between images, ability to show images in random order, ability to expand small images, or even to add a synchronized sound track.

Once an application is chosen, and parameters set, the slide show begins. Viewing is usually on the monitor, but may also use a video projector and a screen). The colors you are able to see are limited to the millions of colors. Displays of images are limited to type of file, monitor resolution, monitor size, and application chosen to view a slide. Bottom line is that you can must plug in the computer (or turn it on in the case of a portable), find the files you want to view, select an application to read the file, and then sit back and view the images on a monitor.

As stated above and in part one, digital images complement analog devices to view images. There are different - but not unimportant - limitations in creating, storing, and displaying digital images. A common limitation between displaying images is that electricity must be available, but analog slides can be viewed with handheld devices using ambient light.

However, the ability to manipulate images from many different sources, the ease of displaying many images, and the freedom to display images under varying light conditions are welcome when presenting images to families, friends, colleagues, and clients.

Now I have another reason to put that PowerBook 540 on my Christmas list....

Note: the views above is from a weekend warrior point of view. If there are errors, omissions, or flat out mistakes, you're comments are most welcomed.

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