Meet the Seatool 40D/50D Underwater Housing. With the EOS 40D/50D, Canon has again set a new standard for mid-range digital SLR cameras and produced a worthy successor to the venerable 20D and 30D line,. The 40D maintains the excellent quality and superb functionality of its predecessors, includes a truly impressive optical viewfinder, and opens up a whole new dimension with its live view option.