His device will reportedly stream damp air containing microscopic water particles through a tube, while a laser diode beams light through the vessel onto a sensor located on the opposite side.
Many advanced amateurs and hobbyists had commented that it was difficult to use when shooting close-up photography on a tripod, for example, because the sensor is on the front of the camera. so we included a remote port on the left side of the camera so you can plug in an optional electrical cable release with a locking switch.