Photo slides, also known as transparencies or positives, are a type of photograph viewed by shining light through them.
Understanding Photo Slides
Photo slides represent a historical format for viewing photographic images. Unlike traditional prints that you hold and look at with reflected light, slides are designed to be seen using light passing through the film.
Definition and Characteristics
Based on their design and viewing method, photo slides have several key characteristics:
- They are a type of photograph.
- They are also referred to as transparencies or positives.
- Their defining feature is that they are viewed by shining light through them.
- According to the provided reference, slides are described as "positives." However, this source also states that, when contrasted with traditional negatives, slides are "an inverted version of the original image, with light areas appearing dark and dark areas appearing light."
Viewing Photo Slides
Because photo slides require light to pass through the film, they are typically viewed using specific equipment. Common methods include:
- Projectors: Shined light passes through the slide and is magnified onto a screen.
- Light boxes or viewfinders: A light source behind the slide allows for individual viewing.
This method allows the vibrant colors and detail of the original image to be displayed when illuminated.
Terminology Explained
The terms associated with photo slides relate to how they represent the original scene:
- Transparency: Refers to the fact that the film is clear in areas where there is no image, allowing light to pass through.
- Positive: In photography, a "positive" typically means the image shows the light and dark areas as they appeared in the original scene (light areas are light, dark areas are dark). The reference uses this term but also describes the slide as an "inverted version" which is characteristic of a negative.
Photo slides served as a popular medium for viewing and sharing images before the widespread adoption of digital photography.
