Great news for Canon 1D / 1Ds Mark III shooters! At the DEMA Show 2009, we confirmed that the upcoming Canon 1D Mark IV fits perfectly in underwater housings designed for the Canon 1D / 1Ds Mark III.

One issue might be that the 1D4 uses the FEL button to start and stop video. Some housings like the Seacam housing we used for the test, do not provide for access to the FEL button. However, it looks like it will be easy to modify the ISO lever so that it hits the FEL button instead, but then photographers will have to find another way to change ISO. Hopefully, the 1D4 will feature a way to change the video start/stop button so hardware modifications are unnecessary.

Canon 1D Mark IV prototype in Seacam housing

Canon 1D Mark IV prototype in Seacam housing

Eric Cheng with a Canon 1D Mark IV prototype