1. Anatomy & Physiology of a Camera
Photography
2nd Quarter
12th Grade
Miss Guild

2. What do you mean by “Anatomy & Physiology?”
Anatomy: descriptions of the parts of a whole
What are the parts of a camera?
Physiology: how the parts make up a whole functional unit
How do these parts make the camera work, and what are their purposes?

3. Basic Film Camera Anatomy

4. Basic Anatomy of a Film Camera
Top cover
Covers the pentaprism and internal portion of eyepiece
Eyepiece
Allows viewing/preview of image in real time
Pentaprism
Five-sided reflecting prism, bends light twice through right angles to avoid inversion through eyepiece
Focusing screen
Made of flat, translucent material (often ground glass) that allows user to preview and image through the eyepiece
Many different types for different styles of photography (split screen, microprism, plain, etched grid, etc.)

5. Simplistic Path of Light Through a Film Camera

6. Basic Anatomy of a Film Camera
Mirror
Reflects light up through focusing screen and pentaprism to the eyepiece
Mirror blocks shutter (in some cameras), moving up to allow light toward shutter when photo is taken
Lens mount
Interface between camera body and lens
Allows for interchangeable lenses
Many types
Lens
Typically a compound lens made of many optical lens elements
Acts as a projector, bending light through the aperture towards the mirror/shutter
Two most important parameters are aperture and focal length

7. Diagram of Focal Length, Optical Center, and Focal Point

9. Diagram of Lens Aperture

12. Basic Anatomy of a Film Camera
Shutter
Depending on camera, can be just in front of film (leaf) or covering lens aperture (diaphragm), or in between (central).
May be purely electronic (often used in combination with any of the three above in some digital cameras)
Shutter speed is how long the shutter remains open to allow light through to film
Aperture refers to the size of the shutter opening
Film plane
Where film is situated behind the shutter, is kept taut and straight by film pressure plate
Film pressure plate
Positioned behind film away from the shutter, supports film and keeps it steady as it is exposed
Back lid
Rear lid of camera, allows for film to be changed
Camera body
Plastic body of camera, encasing all other parts

13. Simple Leaf Shutter

14. Diaphragm Shutter with Aperture Diameter

20. The Three Pillars of Exposure
Shutter Speed
How long film/digital sensor is exposed to light
Aperture
Size of the opening for light to pass through
Sensitivity (ISO or ASA)
Measure of how sensitive the medium (film or digital sensor) is to light

21. Talking about ISO
ISO is a measure of sensitivity, and is an easy setting to manipulate
The ISO varies inversely as the light required for the same exposure
If you double the ISO, you halve the amount of light required
Understanding ISO requires understanding the balancing act between keeping image crispness and getting the required light for an image
Photographers tend to try to keep the ISO low (creating low noise/graininess) for high quality images, but this requires a very fast shutter speed
Many newer cameras have Auto ISO option that will increase ISO when shutter speed is too low for desired photo quality

24. The Exposure “Balancing Act”

28. Please study: Labeled diagram of camera and parts listed
Basic path of light through a camera
Locate, label, and name parts, draw path of light, etc.
Focal length
image slides, know what its’ effects are
Aperture Guide
depth of field!
Shutter speed
image slides, know what its’ effects are)
Three Pillars of Exposure/Exposure Triangle
Understand “balancing act” table
Be able to describe exposure triangle and relationships between all 3 pillars