View source for Gain

Gain, also called ''brightness gain'' or ''luminance gain'', is the measurement of the increase in brightness between the input and the output of an [[Image Intensifier|image intensifier tube]].

== Specification ==
There are two different ways of specifying gain.

=== Imperial ===
Gain specified in imperial units uses the units of foot-Lamberts by foot-candle (<math display="inline">\mathrm{fL} / \mathrm{fc}</math>).

To measure gain in accordance to the [[MX-10160#MX-10160/AVS-6|MX-10160/AVS-6]] specification, the photocathode is exposed to <math>2 * 10^{-6} \mathrm{fc}</math>. A photometer is then used to measure the brightness of the phosphor screen (in <math>\mathrm{fL}</math>). The resulting value is divided by <math>2 * 10^{-6}</math> to obtain the gain in <math display="inline">\mathrm{fL} / \mathrm{fc}</math>.<ref>http://everyspec.com/MIL-SPECS/MIL-SPECS-MIL-I/MIL-I-49428_53852/ (page 8, item 3.6.8)</ref>

To further test auto brightness control, the same procedure

== References ==
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