Team Captain: Ryan Peng
Team Size: 1
Grade Category: 10-12
Subject Area: Engineering/Computer Science
Project Type: Descriptive Project Type III Engineering Project
Language: English
Source of Project Idea:
Using a speedlite to provide fill light for reducing the contrast of a scene is a very valuable feature to photographers. On a typical sunny day, the "sunny 16" rule states that f/16 and a shutter speed of 1/125 seconds should be used for ISO 100. Once you mount an external flash, the camera defaults to a shutter speed of 1/250 seconds. Most compact digital cameras, such as the Canon G9, have a maximum aperture f-number of 8. The combination of f/8 and 1/250 seconds is already one stop over exposure even without the extra fill light. This makes the speedlite useless for fill light. This project will solve the problem by allowing the use of higher shutter speeds with a speedlite.
Project Summary:
A technique was developed to allow the use of external flash at shutter speeds higher than the maximum sync speed. A method to use the camera to measure flash was developed by using a grey card. A mathematical model for the clipped flash output was developed by integrating the flash discharge curve and validated by experimental data. A computer program was created to calculate correct flash exposure.
Software Tools Used:
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Adobe Photoshop
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Microsoft Office 2007
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Microsoft Visual Basic 6.0
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Mozilla Firefox
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FileZilla FTP Client
Hardware Tools Used:
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Compact digital camera
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External flash
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Grey card
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Light meter
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Computer
Special Skills Used:
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Visual Basic 6.0 (Computer Programming) Skills
Awards:
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Best-in-Fair at the Saskatoon Regional Science Fair 2009
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Travel Grant to CWSF 2009
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Senior Innovation Award
Past Virtual Science Fair Websites: