Now that an increasing number of cameras and lenses are “weather-sealed” (such as my Sony a7 and Sony 70-200 f/4), is it still a good idea to use a Ziploc bag when shooting in the rain?
That’s an excellent question, Véronique, and here’s the short answer: except in a light drizzle, I would still take steps to protect a weather-resistant camera and lens. That’s because none of the warranties covers damage caused by water. Note too that the degree of weather-resistance depends on the specific camera and lens. At this time, the information provided by Sony Canada’s website does not indicate that the a7 is moisture-resistant, but it does state that the 70-200 f/4 lens features a “dust- and moisture-resistant design” without additional specifics.
Pentax discusses the extent of water-resistance for its K5 series and WR series lenses on their US website; that information suggests that such equipment might be able to withstand quite a bit of rain or wet snow. Nikon and Canon also publish diagrams that show the seals in some of theirs, and these are quite impressive. However, none of this information tells the user whether the equipment can withstand heavy rain, or for how much time.
My research has not turned up any tests of the extent of the water resistance of any cameras. One website, LensRentals.com (in the U.S.), has disassembled a few cameras and lenses, and their reports briefly comment on the amount of obvious weather sealing. However, they have also not conducted tests as to the amount of water that any specific piece of equipment can withstand. In fact, the owner of that site, Roger Cicala, posted the following comment in reply to a reader’s question about a teardown report. “My faith in weather resistance will reappear after …. a guarantee in writing from the manufacturer that a camera is weather sealed. You want to know how many ‘weather sealed’ cameras and lenses we write off for water damage every year?”
A large Ziploc bag, used correctly to ensure an effective seal, may be useful but there are better solutions such as the Pro Light Camera Cover series from Manfrotto (previously marketed under the Kata Elements brand). They are available in configurations to suit specific types of cameras and lenses. The cost varies from about $50 to over $100, depending on the size and type. For example, the Pro Light E-702 PL, $100, is designed for a DLSR with a 70-200 mm f/2.8 lens attached. I have used one of these in driving rain in Florida, and the cover kept the equipment perfectly dry. Regardless of the brand of accessory you buy, read the manufacturer’s instructions regarding correct installation (and any warnings) to get the most effective protection.