Project Overview:
A modified version of the SPC was commissioned by Rob Campbell from the Prince William Sounds Science Center in Cordov, AK to be mounted on his profiling mooring in the Prince William Sound. The profiler typically runs several times a day sampling water from the surface down to 60 meters at a profile speed of roughly 30 cm per second. The profiler holds an excellent suite of sensors that provide a host of biological and physical measurements. The custom designed SPC will augment these sensors with high-resolution images of plankton in the size of of 1 mm up to several cm. In order to collect enough samples during the relatively short and infrequent profiles, the SPC was redesigned around a much larger field of view (over 500 mL volume images per frame) and housed in a larger set of tubes with large sapphire optical ports. Working with Wetlabs the SPC was integrated as an additional sensor in the suite of instruments on the profiler.
General Information:
The system is built around a 0.137x telecentric objective made by Opto-Engineering. Large pressure housings with massive sapphire optical ports were used to achieve a field of view with over 100 mm diagonal and a working field depth of nearly 140 mm (for objects > 1 mm). The latest ODROID 8-core ARM CPU and 12 MP USB camera were used to give up to 7 fps with roi detection in real-time. The illumination system for this very large field of view was custom designed to give good contrast darkfield images over a very short path length.
People:
- Principal Investigators: Jules S. Jaffe, Rob Campbell (PWSSC)
- Principal Engineers: Paul L. D. Roberts
- Mechanical Engineers: Devin Ratelle