Transcript Estimating Power Consumption: Olympus E-1

Estimating Power Consumption:
Olympus E-1
Scott Kirkpatrick
Where does the power go?
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Major components
– Imager (analog + A2D), compression asic,
DSP, memory and memory management, USB
– LCD for viewing pictures, histogram, etc.
– Lens controls – autofocus, autoexposure
– Shutter and mirror mechanisms
– Startup stuff – e.g., the dust-buster
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Controls available to the photographer
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Manual operation
Use of standby power-down
The “half-press”
Choice of Tif, RAW, JPG and quality level of output
Emphasise maximizing the number of pictures
per battery charge
How to measure this
• Use a computerized external power supply
• Operate with battery out of camera
– (does this make it operate differently
• For example, it won’t go into standby state
• Fix voltage at 9V, monitor current used on
a PC through GPIB card, connection to
power supply
Startup, half-press, shutdown (AE,AF)
Startup, focus, shutdown (MF)
Taking and saving pictures
of various sizes
From left: TIFF, SHQ, HQ, SQ, Raw file
Focusing my heaviest lens (200 mm)
Effect of most available controls
• Matter less than the basic cost of operation
• Battery is 1.5 A-hr (4X what a cellphone has).
This covers 7.5 hr of operation with no pictures
taken. Basic cost of operation is 0.2 A.
• Taking a picture, focusing the lens, momentarily
increases workload to .25 or .3 A. Still 5 to 7.5
hrs of operation.