Does the Panasonic Lumix DMC-G85 have an internal fan?

Question

When I switch on my Panasonic Lumix DMC-G85, there is a distinct (albeit faint) sound coming from inside the camera body. To me, it sounds like a small fan, not too dissimilar from what you'd find inside a laptop body. Considering the camera is constantly active, showing frames either on the eye socket or the screen, and it handles 4k video, it wouldn't surprise me if it needed some active cooling.

Question: Does the G85 have an internal fan? If not, what exactly is the constant sound that I'm hearing come from the inside of the camera body?

Others have theorized that it's related to the in-body image stabilization (IBIS), although I struggle to see how such a component could create so much constant noise (again, it's not that loud, just noticeable).

I have to put my ear up to the camera body in order to hear the sound, so this isn't a complaint. I'm just trying to learn a little about the internals of the camera body.

Answer 1

I have similar noises in my Canon EOS RP.

Firstly, when I turn the device off or change a lens, there's a ~2 second fan-like noise. It's the ultrasonic sensor cleaning apparatus. It's entirely possible your camera uses the sensor cleaner when turned on and not when turned off. I like more the cleaning cycle when turned off because you won't be needing the camera for few seconds after you turned it off.

Secondly, when I use an image stabilized lens, I hear the lens-based image stabilizer working. It sounds more like clicking than a fan, but there's some minor fan-like noises as well.

Your camera has IBIS, so it certainly could be the IBIS.

I don't see the benefit of adding a fan to a camera. Typically, the batteries are so small that to have useful battery life, the energy consumption of all components needs to be minimal. Similar to smartphones, actually. When heavily used, a camera could in theory overheat (affects some mirrorless models more than other mirrorless models or DLSRs). But I have never heard about a fan in a camera to combat overheating.

Also, camera bodies might use switch-mode power supplies (SMPSs). They could result in coils ringing, at an audible frequency. Good devices have the SMPS sounds so faint that you don't hear them in typical use, but putting your ear next to a device is not typical use.

Answer 2

If it happens when you switch it on, it's almost certainly not cooling - none of the activity you mention will have happened, and the camera components will be cooler than they would be during extended operation.

If it only happens when you switch it on, the idea of a sensor cleaning system becomes likely.

If it also happens while composing a shot (and particularly if it happens at slower shutter speeds but not higher), Image Stabilization would be the most likely interpretation.

You could try switching stabilization off (link here - page 145) to see if the sound is still there. I didn't see a reference to sensor cleaning, but that doesn't mean it doesn't have it.