Polaroid ProCam Repair Manual page 21

Figure 1-13. Hybrid Light and Distance Measurements
ProCam Light Measurements
As in the Spectra system, a brightness detect reading is taken by the
exposure circuitry during Preview. Scene brightness is measured at this
time and is categorized into:
High Brightness
Low Brightness
This brightness information is used to determine strobe firing timing. A
second brightness detect reading was added in the upgrade. During this
second reading, the exposure system categorizes scene brightness into:
High Brightness: > 24 cd/ft
Mid Brightness: 8 to 24 cd/ft2
Low Brightness: < 8 cd/ft
DUAL PHOTODIODES
PROVIDE LIGHT INFORMATION
TRANSDUCER PROVIDES
DISTANCE INFORMATION
2
- above 12 cd/ft or,
2
- below 12 cd/ft
2
2
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