A method for monitoring a plurality of tagged assets on at least one offshore asset, by creating a customer profile and a library of survey set ups and storing information from independent survey set ups mounted on or proximate to the offshore asset on the administrative data storage. Lenses and apertures may be used in place of or in combination with one another, and may be disposed in or on full frame, half frame, wire frame or rimless eyeglasses. The gain adjust circuit can be arranged as a trim adjustment to the overall gain of the PGA circuit, where a different trim adjustment can be mapped to each gain setting such as from a look-up table.