SLR
SLR is the acronym for Single-Lens Reflex.

Single-Lens Reflex
A term used to describe a type of camera that uses a mirror and prism system to allow photographers to see through the lens and view precisely what will be captured. This design distinguishes SLR cameras from earlier types, where the viewfinder and the lens were separate, leading to potential discrepancies between what the photographer saw and what was photographed. Here’s how an SLR camera typically works:
- Viewing the Image: Light enters through the lens and is reflected by a mirror positioned at a 45-degree angle inside the camera body. This light is then directed upwards into a focusing screen.
- Prism System: Above the focusing screen, there is a prism (usually a pentaprism) that corrects the orientation of the image, allowing the photographer to see a correctly oriented image through the viewfinder.
- Taking the Picture: When the shutter button is pressed, the mirror flips up out of the way, allowing light to pass directly onto the film or digital sensor, capturing the image.
The SLR design has several advantages:
- Accurate Framing: Since the viewfinder shows precisely what the lens sees, it’s easier to compose shots accurately.
- Lens Flexibility: SLR cameras typically allow for interchangeable lenses, offering a wide range of focal lengths and types of lenses.
- Depth of Field Preview: The photographer can preview the depth of field before taking the photo, which is helpful in determining which parts of the image will be in focus.
With the advent of digital photography, the term DSLR (Digital Single-Lens Reflex) has become common. DSLRs use the same mirror and prism system but replace the film with a digital sensor. Despite the rise of mirrorless cameras, which eliminate the mirror system for a smaller and often quieter design, SLRs and DSLRs remain popular for their optical viewfinder clarity, lens compatibility, and overall performance in various photographic situations.
- Abbreviation: SLR