Z9. Never

One thing moving to mirrorless is that you are supposed to turn off most bodies before swapping lenses. Most mirrorless systems close the shutter when turned off (as well as Canon stopping down the aperture and shifting focus to infinity) and you are only supposed to swap lenses while the body is off so as to lessen the exposure of the sensor to dust and contamination.

With DSLRs, the mirror box makes this much less of a problem, and the mirror being dusty isn’t really a huge issue. It’s something I have definitely had to become much more attentive of moving to mirrorless systems.

Rarely because i don’t change lenses a lot and if i do it is never outside

Fuji GFX and Canon RF shooter, both since early 2021, never been an issue. I don’t change lenses too often but I’m not exactly in a clean-room when I do.

Sony A9. Pretty much no dust ever, despite swapping lenses all the time as an event photographer. I point the mount downwards before swapping lenses, seems to do the trick.

On my Nikon I experience sensor dust when I stop down to f/14 or more and shoot something that is a single color.

Other than that I don’t notice it. I don’t clean the sensor more than every year or so.

I have a terrible habit of switching lenses in the wind, i need to clean seasonally

dude! My A7C is SO BAD. I shot wildlife with a Panasonic G9 and documentaries with a GH5 and NEVER had dust, even in real sketchy jungle environments. Switched to Sony and BOOM. Constantly dusty. No clue why it’s like that

Never and I shoot Sony and switch primes a lot.

I have an a7iii as well and this thing collects dust like crazy

I take so many photos, hit f11 and shoot the sky and find myself hurt by the amount of dang spots I see

I clean it almost every 3 month.

Wtf is going on with this camera?

I don’t know why they don’t make the shutter automatically close when you take the lens off?

I shot Olympus and Pansonic M43 for several years before going Sony FF. I cleaned a spec of dust one time ever on my G9 with a blower. I take my cameras hiking as I do landscapes so I’m constantly in rough conditions.

My Sony FF gets so dirty sometimes even the cleaning function and blower doesn’t do it and I resort to sensor wipes. The sensors literally act like dust magnets for me. It doesn’t matter whether the lens I’m using is weather sealed…even without swapping lenses after a few weeks of use I have dust showing up in my photos. It only takes on lens swap and I’ll be cleaning numerous dust specs from the sensor in post. Been through two A7R2s that both do this.

I have the old Sony alpha 850 and I get dust every time I change lenses. Retouch in post, but I shouldn’t have to.

Sony sensors are notoriously bad at discharging the sensors when powering down. That creates a lot of static. I recently switched from Fuji to Sony and I have had dust spots 4 times in 3 months. Compared to 0 times in my 2 years with Fuji. A local Fuji user also carries his full kit without a single lens/back cap. And he stores lenses in his pockets without lens caps and gets zero dust issues.