Camera Control

Exposure

Under Exposure and Over Exposure

• Exposure = Aperture + Shutter + ISO
• Histogram = a graphic representation of distribution of overall tone value
• Use your light meter to determine
  • Incident Light Meter
  • Reflected Light Meter - more common

Reflected Light Meter & Meter Modes

• Treat the middle light it measures as middle gray, i.e. assumes it reflect 18% of the light
• Meters work best when the scene is evenly lit
• Metering Modes
  • Evaluative/Matrix/Multi - measure multiple regions and figure out the best result
  • Center Weighted - measures the middle area, used in portraits
  • Spot, Partial - usually used in extreme high contrast

Equivalent Exposure Combinations & MAPS

• Manual Mode - sets shutter speed and aperture manually
• Aperture Priority Mode
  • Chooses the aperture first, others are calculated
  • To ensure the deep/shallow depth of field
• Program Mode
  • Automatically adjusts shutter speed and aperture
  • Best when you have to make decisions quickly
• Shutter Priority Mode
  • Chooses the shutter speed first, others are calculated
  • Best when movement is involved

Stop Action and Blur

• Choosing a fast enough shutter speed
• The direction of the movement. If it’s directly moving towards you or away from you, slower shutter speed is acceptable
• The distance of the subject, closer = higher shutter speed
• The focal length, telephoto lens = higher shutter speed
• Shutter Lag and Focus Lag

The Lens

Focal Length Basics

• Pupil focal length = 17mm in average
• “Normal” depends on sensor size
  • Full Frame 36mm x 24mm → 50mm
  • APS-C 17mm x 23mm → 30mm
  • Four Thirds 21mm x 17mm → 25mm
• Diagonal of the film/sensor is the normal focal length!
• “Normal” is about perspective, not about the field of view
• Perspective is not only a function of objects, but also of the position of the camera.

Focal Lens Effects

Focal Lens Specialties

Lens Accessories