Why Underwater Housing Matters
Your camera is not waterproof. Even a brief splash on the wrong production day can destroy a sensor worth tens of thousands of dollars. Underwater housings are the pressure-sealed enclosures that protect cameras during submersion — and choosing the right one is as important as choosing the camera itself.
Types of Underwater Housings
Hard Acrylic / Polycarbonate Housings
These are the most common housings used by working cinematographers. Made from machined aluminium or high-grade polycarbonate, they offer depth ratings from 40 metres for recreational systems up to 100+ metres for professional cinema rigs. They are custom-designed for specific camera bodies, meaning controls, dials, and buttons are accessible through port extensions built into the housing.
Soft Bags / Underwater Sleeves
Soft housings are inexpensive and lightweight, designed for shallow water or splash protection rather than true submersion. They are suitable for behind-the-waterline shots at the surface but should never be used for dedicated underwater sequences. Think of them as splash guards, not diving gear.
Cinema-Grade Custom Enclosures
For large-format cinema cameras (ARRI, RED, Sony Venice), custom housings are built by specialist manufacturers. These are often bespoke units fabricated to the exact body and lens configuration of the production. Depth ratings vary but are typically engineered for the specific demands of the project.
Key Specifications to Evaluate
| Specification | What to Look For |
|---|---|
| Depth Rating | Match to your deepest planned shot, with safety margin |
| Port Compatibility | Flat port for wide lenses; dome port for zoom/normal lenses |
| Vacuum Seal Testing | Always use a vacuum/leak indicator before submersion |
| Control Access | Ensure focus, iris, and record controls are reachable |
| Monitor/EVF Access | Check for external monitor port or built-in viewing window |
Flat Port vs. Dome Port
This is one of the most frequently misunderstood choices in underwater cinematography. A flat port introduces refraction that effectively magnifies your focal length by approximately 1.33x underwater — useful with wide-angle lenses to counteract the narrowing effect. A dome port corrects for refraction by using a curved front element, preserving the intended field of view of the lens and allowing genuinely wide shots. For most cinematic work, dome ports are preferred.
Pre-Dive Checklist
- Inspect all O-rings for cracks, debris, or deformation. Replace any that look worn.
- Apply O-ring grease sparingly — a thin, even coat only.
- Assemble the housing in a dry, clean environment away from sand and salt water.
- Conduct a vacuum seal test and hold for at least 5 minutes before entering water.
- Do a shallow test dive before committing to deeper or longer shots.
- Have a surface tender watching the housing during all underwater work.
Rental vs. Purchase
For productions that don't shoot underwater frequently, renting is almost always the better choice. Housings are camera-body-specific, and as productions upgrade cameras, purchased housings become obsolete. Specialist rental houses maintain and recertify their housings regularly, which adds an additional safety layer you don't get from a privately owned unit sitting unused between projects.