My own experience has been the Z body has been very resistant to dirt on the sensor, compared to any of my DSLRs. I have wet cleaned it once when we...the camera and me...were caught in crop duster pass my glasses were a mess but one big spot on the sensor, the wet slurry got us right when changing lenses, with the flange pointed down. Otherwise no other cleaning. The built-in system seems to work well due to the new coating on the Z sensors. If you do need to clean it, so close to the flange, it is a much faster, easier job than on a DSLR. Stan St Petersburg Russia
Stan
St Petersburg Russia
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