Underwater camera housing rarely leak, but if this event occurs the results are normally catastrophic causing irreparable damage to the camera body and lens.
SparkFun published a water detector project in 2013, where the original design was intended as a replacement for a NautiCam leak sensor. This project adapts the SparkFun design to an AdaFruit Trinket. The resulting implementation is sufficiently small as to fit within an Olympus PT-EP14 housing (e.g. for the Olympus OM-D E-M1 Mark II body).
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