Build and Weather Sealing

You could easily describe the build of the 5D mark 3 as solid. At its core, the camera is a machined magnesium body, exactly what you’d expect from a pro level camera. The optional battery grip is built to an equally solid standard as well. All told, the camera weighs some 33.5 oz (950g) with the battery. Adding the optional battery grip ups the weight to about 3-1/3 lbs. (1.5Kg), making the combination quite hefty, and about the same weight as an EOS-1D X give or take a bit.

All the surfaces you can expect to have to handle are wrapped in Canon’s standard textured rubber material. The remaining surfaces are finished in what looks a lot like black powder coating. Overall, the fit and finish is exactly what I expect form a Canon pro level SLR, solid and without any noticeable flex or squeaky parts.

Canon calls out the weather sealing in their marketing material. Bear in mind though, this is weather sealing not water proofing. The camera is designed to stand up to rain, not being immersed or submerged. Joints in the body and the buttons are gasketed to prevent water intrusion. Both the card slot and battery doors are obviously gasketed as well.

The connectors for the remote release, PC sync port, external mic, headphones, AV/USB, and HDMI out are covered by two rubber flaps (for lack of a better word). When nothing is plugged in the connectors should be well protected, however, plugging something in exposes all of the connections on that half.

Compared to Nikon’s D800 port coverings, Canon’s solution does leave some things more exposed. For example, on the D800 the PC sync and remote release terminals are separate from the rest of the ports, and can be used without exposing anything else. On the 5D mark III, attaching a remote release or a PC sync cord, exposes the remote release, PC sync, and mic in ports.

The optional BG-E11 battery grip continues the weather sealing with gasketed buttons and gasketing around the battery tray cover. Though the interface between the camera and the grip isn’t gasketed and the gasketing appears missing around where the battery door would have been on the grip. Though, I’m not sure how much of an issue that actually is in practice.

The most visible difference between the weather sealing on the 5D mark 3 and the EOS-1D bodies, is the omission of the plastic ring around the lens mount for seating a sealed lens’s gasket. Ultimately, I’m not at all sure how necessary this detail is in actually sealing the joint, as when attaching a lens to either my 1D or my 5D mark 3, the gasket around the lens is equally compressed. The only real difference is whether the lens’s gasket is landing on a smooth plastic surface, or on the very slightly textured surface of the camera’s coating.

As to how well the weather sealing works, well that’s something I’ve never really tested. I’m more than comfortable taking my 5D mark III out in a light drizzle, but anything more than the lightest rain and I’m putting a raincoat on my camera or it’s going back in a weatherproof camera bag. The simple reality, for me at least, is that it’s not worth trying to find out just how far I can push a weather-sealed camera before the weather sealing can’t stand up to the onslaught.