Exposure & Settings: P Exposure & Settings

Exposure & Settings: P-2202 Topics Relationship between ISO, shutter speed and aperture Purpose and use of pre-focus Exposure Lock Selecting various exposure modes Best settings for image resolution and quality for CAP missions 2

Exposure & Settings: P-2202 Camera Lens & Shutter Digital cameras work by opening a shutter for a brief time to let in light that interacts with a light- sensitive photo receptor. Electrical charges are converted into digital bits and stored on a memory card creating images. 3

Exposure & Settings: P Photography Terms Aperture: Controls the amount of light that reaches the picture sensor – Measured in “f number”, e.g. f scale: f1.2 – f22, each increment is a “stop” or ~2x the light – The more light, the faster the shutter speed for a good exposure Shutter Speed: – Typically measured in fractions of a second (e.g. 1/800th of a second, or just “800”) – Faster shutter speeds reduce blurring of image due to motion or vibration Example relationship of aperture vs. shutter speed for a given ISO setting

Exposure & Settings: P Photography Terms Focal length (Zoom): – Measurement of distance from lens to picture sensor (in millimeters, mm) – The larger the number, the more the zoom & the higher the sensitivity to effects of vibration ISO: Adjusts picture sensor’s sensitivity to light – Higher number means higher light sensitivity & faster shutter speeds – But, higher numbers may result in a more “grainy” or “noisy” picture Focal Length (Zoom) Picture Sensor Lens Low Zoom High Zoom

Exposure & Settings: P-2202 Camera Switch Settings 6 Lens AF: AF Optical Stab.: On Camera AF: AF Mode Sw: Auto/No Flash Power On Shutter Release Camera display should look something like this when set up correctly

Exposure & Settings: P-2202 Pre-Focus Exposure Lock Difficult to use Manual Focus in an aircraft Autofocus- lens/camera work together as a unit Pre-Focus Exposure Lock allows the camera to make focus adjustments prior to actually taking image. – Activated by pressing shutter release button briefly at a half-way point. – Activating pre-focus causes camera to lock autofocus into sharp focus and measures light level to determine exposure. 7

Exposure & Settings: P-2202 Exposure Modes Automatic (A) mode – camera determines combination of aperture, shutter speed and sensitivity based on camera’s light metering system. – Auto with Flash Off is recommended setting Program (P) mode- similar to Automatic mode but allows for manual modification of aperture or shutter speed 8

Exposure & Settings: P-2202 Auto Focus Modes AF-A is recommended to help ensure a focused photo 9

Exposure & Settings: P-2202 Single Shot vs Burst Mode Single shots allow camera to adjust to changing light and focus conditions after each shot. – Best use is in shifting lighting conditions (ie: clouds) Continuous Shooting (Burst) Mode locks in a setting and utilizes that setting for a series of shots taken in continuous manner. – Best use is in turbulent conditions 10

Exposure & Settings: P Image & File Size Tradeoffs D90 Image Size vs. Quality Settings = ADIS Kit: CAP NHQ recommended settings (L: quality stays higher when image is enlarged) (compression ratio ↑, quality ↓) Image Quality Setting

Exposure & Settings: P-2202 D90 GPS Considerations Check Auto Meter Off Delay Status – Ensures GPS is stays powered up between photos – Recommend setting to 30 minutes – Access thru MENU,, TIMERS/AE lock, Auto Meter Off Delay 12 Auto Meter Off Delay

Exposure & Settings: P-2202 EXIF data/Metadata Both RAW and JPEG formats contain encoded information – Information includes shutter speed, aperture, date/time of photo – If GPS attached the data includes latitude/longitude and altitude of each photo 13 Image file contents

Exposure & Settings: P-2202 Summary of Camera Settings 14 6 Install memory card (card may already be in the camera) by opening the door located on the right side of camera and gently pushing the card in until it clicks in place. A light located on the back-right of the camera will briefly illuminate to confirm the card is seated. The card can be removed by pushing the card in and it will pop out Set the lens auto focus switch to AF Set the camera auto focus to AF Set Program Mode selector to Auto with no flash