Remove the lens from an SLD camera and there, seemingly unprotected from cack-handed or simply luckless lens changes, is the sensor. It sits permanently exposed, waiting for calamity to befall it. Does that mean these cameras are disasters waiting to happen?
It may seem pedantic, but the component behind the lens on a mirrorless camera isn't actually the sensor; it's a thin sliver of glass which, on most SLDs, vibrates to dislodge specks of dust. The sensor itself - the component that gathers light and translates it into data - is behind that.
According to an expert at a premier camera shop, the sensor is quite rightly left exposed. Like any properly cleaned glass, the filter over the top of a camera's sensor can be cleared of smudges or particularly stubborn specks of dirt without damage.
The only other way to hide the sensor when a mirrorless camera is open would be to have the "wafer-thin" shutter assembly permanently closed, something our expert believes would be the wrong move. "Shutters are very robust in use, [but] fragile with misuse." Poke that with a finger, and the result would likely be more serious than prodding the sensor.
Panasonic, Olympus and Samsung all told us that it was possible to have their cameras serviced and the filters replaced. What was more difficult to ascertain was the price of doing so. UK high-street retailer Jacobs doesn't perform the service, and professional outfits generally don't work on non-DSLRs. Olympus said it charges a flat fee for all repairs on its cameras; not cheap.
It isn't all bad news, however. Our source says his shop hasn't seen a damaged sensor filter yet, but there are a few measures you can take to avoid becoming the first.
The most obvious is to take great care when changing lenses. Never swap lenses outdoors, for instance - a split second is all it takes for a well-aimed splash of rain to enter your camera's body. We'd also urge great caution when cleaning your sensor.
Never poke around with a swab or cotton-wool bud if it wasn't expressly intended for the job, and even with so-called professional solutions, make sure you've tried other, contactless ways of cleaning your sensor first - a hand-powered air blower normally proves effective. Failing that, take it to a shop and have an insured, experienced professional do the sweating.