The development of a small and inexpensive photometer for determining light intensities and photographic exposures is described. A study is made of the performance of two types of instrument. In a large number of readings by a single observer with the smaller type it was found that the average error in measuring exposures on neutral colored objects was 22% which corresponds to about 7% difference in the density of the photographic image. The larger type had a precision of better than 5% for most of the range.
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