# T&P 2A – Outcome 2 -Inverse Square Law 1-Experimentation and Outcome – Page 51-54

Inverse Square Law

Double the distance equals 1/4 of light intensity.

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Reciprocity Law Failure

exposure= intensity x time

This equation “breaks down at extremely long ( and short ) exposure times, known as Reciprocity failure.”(Langford, Fox & Smith, 2010)

Colour Temperature

Is calculated in Kelvin (k). In digital cameras like the DSLR it mostly attained from the white balance, where colour variants can be obtained from here. For a photographic film the colour temperature might vary even more. One should make sure that the colour balance is well corrected as it might result into an orange or blue effect when printing out the photos. The neutrality and balancing is the ultimate goal when working with Film photography.  Film and Camera stills obtain their white balance from the objects that they are projecting with.

After analyzing the Inverse Square Law , the concept of reciprocity law failure and colour temperature I wanted to try to capture the real thing. Through employing different time speed; 1 sec, 8 sec, 1 min etc i was able to see the different outcomes of every shoot.

Bibliography :

Langford, M., Fox, A., & Smith, R. (2010). Langford’s basic photography (1st ed., p. 449). Oxford: Focal.