At the request of Cawthron Institute, Bay Dynamics was asked to design and build a custom drop camera system that would allow its operations team to easily conduct spot inspections of the sea floor, at scale, for the greatest number of sites possible in the shortest amount of time. It had to be easy to operate by any Cawthron Scientists and it had to use off the shelf parts where ever possible.

Bay Dynamics took the challenge up and created the Mk3 Drop Camera. A robust and easily transportable 300m rated drop camera.

It used a 12Mp 4K Camera with x3 zoom and utilised dual, easy swap, batteries combined with 2 channels for up to 8 lights for the operator to place as needed. The frame allowed for adjustments in many ways and allowed for a Quadtrac Frame for photo references. The topside control box was designed in a way that allowed for three different methods of operating the unit in the event of hardware damage. These included:

• *Laptop control of camera and lights.
• *Touch screen control via the topside box
• *Physical controls via the topside box

The topside box featured self diagnostics capability that could identify faults both with the topside box and the subsea hardware in real time, pinpointing fault finding locations for the operator. Two accessory ports allowed the addition of echosounders and sonars, and additional cameras if required.

All video and data was available via an overlay system running through OBS, a free online software to ensure perpetual use at no cost.

The entire system was designed in a modular way, allowing Cawthron the ability to remove the housings from the primary frame and utilise the entire system in other frames, such as their own tow frame for transect pulls across the seafloor over distance.

To date, this system has been used many times to further Cawthron’s research studies for itself and clients around New Zealand.