Camera Control - Digital

Web: www.daybell.com/cameracontrol

ISO Speed (how sensitive the CCD is to light)

Labeled as ISO (but also referred to as ASA)

• 1600: very fast, for low light, noisy

• 800: fast, for low light, can be noisy

• 400: medium, good choice for indoor

• 200: medium-slow, for daylight or indoor

• 100: slow, for daylight or flash

ISO 200 is twice as fast as ISO 100, and ISO 400 is twice as fast as ISO 200 and so on

ISO speed affects image “noise” (small unwanted speckles found in dark areas of the image) – the higher the ISO, the more noise

ISO speed also affects contrast - ISO 800 is higher in overall contrast and 100 is lower in overall contrast

Aperture (the lens opening):

Measured in f-stops, common f-stops are: f/22, f/16, f/11, f8, f5.6, f4, f2.8 (f-stops are not limited to just the fractions listed above but may vary from camera manufacturer to camera manufacturer and from lens to lens)

F-Stops are expressed in fractions (technically they’re fractions of the lens’s “focal length”) therefore:

• f/11 is a smaller opening than f/2.8

• f/5.6 is a larger opening than f/8

Each f/stop is half as large or half as small as its predecessor or successor

• f/5.6 lets in twice as much light as f/8

• f/5.6 lets in four times more light than f/11

• f/11 lets in half the light of f/8

Depth of field

• The larger the aperture the less depth of field

• The smaller the aperture the more depth of field

Note: Depth of field is also affected by other factors such as focal length and camera to subject distance, these factors are best learned through experience

Shutter speed (length of time the camera allows light to reach the sensor):

Measured in seconds or more commonly, fractions of second. Common shutter speeds are: 1/1000, 1/500, 1/250, 1/125, 1/60, 1/30, 1/15 (like f-stops, shutter speeds are not limited to fractions listed above but may vary from camera to camera)

Generally speaking, shutter speeds 1/125 or faster will stop motion while shutter speeds slower than 1/125 can blur motion (however, these are only generalizations and speed of subject will greatly affect outcomes)

Exposure (Your camera will need to be in the M mode (for Manual) to manually adjust either the ISO, f/stop or shutter speed):

1. Check to see the ISO setting on your camera, generally this is found in the “Menu.” If you don't, you run the risk of making a noisy, overly contrasted and possibly blurry image. Remember, you can change the ASA/ISO setting for each shot so don’t limit yourself by setting the ISO at the beginning of the photo session and forgetting about it. Experiment,

2. Look through your camera

3. Point it at the subject you want to photograph

4. Press lightly on your trigger

5. Your light meter in your camera will tell you one of three things depending on how it works:

• A plus or minus will blink indicating that you need to add more light or less light. Try adjusting shutter speed or f-stop until the + or - disappears

• A display of f-stops is shown. You have set your shutter speed, so the camera is telling you which f/stop to use for the correct exposure.

• A display of shutter speeds is shown. You have chosen an f-stop, so the camera is telling which shutter speed to use for the correct exposure.

6. When your camera stops blinking at you and seems satisfied you have the correct exposure, take the photo.

Example:

• Your light meter reads f/8 @ 1/125. This is your normal exposure

• Remember, f/8 at 1/125 is equal to f/16 at 1/30 which is equal to f/22 at 1/8, all these could be considered “correct” exposures