Title

A Perfect Picture: Effect Of Camera Settings On Exposure

Author(s)

Caitlin Kunchur

School Name

Dutch Fork Middle School

Grade Level

8th Grade

Presentation Topic

Physics

Presentation Type

Non-Mentored

Oral Presentation Award

1st Place

Abstract

Purpose: Pictures represent scenes by recording different brightnesses at different locations. A camera has a sensor with many pixels. In each pixel there is stored electric charge that leaks out when light falls onto it, showing the exposure. Besides the scene's brightness, exposure also depends on shutter speed, aperture, light sensitivity (ISO), and resolution (megapixels). Understanding these settings are necessary in order to achieve the best picture possible. / / Procedure: For each experiment take pictures and use GetRGB software to find the mean and standard deviation for all pixels. For each experiment vary only the settings mentioned below while keeping the other settings fixed. / 1) Vary the shutter speed from the fastest to slowest setting. 2) Decrease the aperture and increase the shutter speed so that different combinations maintain a correct exposure. 3)Take three pictures at the lowest, middle, and highest ISO settings, while maintaining a correct exposure. 4) Repeat last experiment changing only the number of megapixels. / / Results and Conclusions: 1)At shutter speed of ¼” the exposure reached its maximum indicating that all charge leaked out 2)Combinations of shutter speed and aperture area when inversely proportional had constant exposures proving reciprocity. 3)As the ISO and number of megapixels increased, the noise increased as well. This was expected because at higher ISOs, less charge is amplified more so any variation or noise will be much more apparent. With fewer pixels, different exposures should be averaged in order to reduce size. This is contrary to the belief that more pixels are better.

Location

Owens 104

Start Date

4-16-2016 11:45 AM

COinS
 
Apr 16th, 11:45 AM

A Perfect Picture: Effect Of Camera Settings On Exposure

Owens 104

Purpose: Pictures represent scenes by recording different brightnesses at different locations. A camera has a sensor with many pixels. In each pixel there is stored electric charge that leaks out when light falls onto it, showing the exposure. Besides the scene's brightness, exposure also depends on shutter speed, aperture, light sensitivity (ISO), and resolution (megapixels). Understanding these settings are necessary in order to achieve the best picture possible. / / Procedure: For each experiment take pictures and use GetRGB software to find the mean and standard deviation for all pixels. For each experiment vary only the settings mentioned below while keeping the other settings fixed. / 1) Vary the shutter speed from the fastest to slowest setting. 2) Decrease the aperture and increase the shutter speed so that different combinations maintain a correct exposure. 3)Take three pictures at the lowest, middle, and highest ISO settings, while maintaining a correct exposure. 4) Repeat last experiment changing only the number of megapixels. / / Results and Conclusions: 1)At shutter speed of ¼” the exposure reached its maximum indicating that all charge leaked out 2)Combinations of shutter speed and aperture area when inversely proportional had constant exposures proving reciprocity. 3)As the ISO and number of megapixels increased, the noise increased as well. This was expected because at higher ISOs, less charge is amplified more so any variation or noise will be much more apparent. With fewer pixels, different exposures should be averaged in order to reduce size. This is contrary to the belief that more pixels are better.