Sponsor: National Science Foundation
The Low-Light-Level Underwater, Multispectral Imaging System-2 is a portable, multispectral, dive camera, designed for rapid in situ fluorescence surveys of coral reefs at multiple emission wavelengths. Fluorescence images of corals have unique advantages over traditional RGB images that can be used to reveal information about the health of the corals, find coral recruits, and help separate corals for other benthic inhabitants.
LUMIS2 is based on a four-camera imaging system where each camera records a single spectral channel (typically narrow band). Three of the cameras are outfitted with high-performance 20nm bandwidth interference filters while the fourth camera is an RGB camera for recording regular RGB images of white light reflectance. Fluorescence emission is stimulated via two high-power blue LED strobe lights that were custom made for this application. In addition to the blue strobe lights, a set of commercial underwater strobes are used to provide white-light illumination. Finally, a pattern project is used to estimate depth information and aid in frame coral subjects during night ops.
The imaging system is controlled by a pico-ITX form-factor computer and a Teensy 2.0++ USB microcontroller. The microcontroller provides microsecond synchronization and triggering for the cameras and strobes. The diver interacts with the system using a custom designed polycast endcap with a 8.4″ LCD display and 10 piezo-ceramic underwater buttons. The buttons are interfaced to the PC using an Ultimarc MiniPac
Software for the system is built in OpenCV and uses the PvAPI from Allied Vision Technologies
- Principal Investigator: Jules S. Jaffe
- Principal Engineer: Paul L. D. Roberts
- Collaborators: Computer Vision Coral Ecology
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