We discuss how compressed images created by modern digital cameras can lead to even severe problems in the quantitative analysis of experiments based on such images. Difficulties result from the nonlinear treatment of lighting intensity values stored in compressed files. To overcome such troubles, one has to adopt noncompressed, native formats, as we examine in this work.
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All the pictures in this work were taken with a reflex digital camera Nikon D80 with intensity calibration at the native value (ISO 100) to avoid electrical amplification after the sensing unit. The lens used is a Nikkor 200 mm set at fixed f/16 diaphragm value. The focus was adjusted in manual mode.
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).© 2013 American Association of Physics Teachers.
2013
American Association of Physics Teachers
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