How P&S with zoom get away from dust attack?

[Einst_Stein]

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It is very annoying to have frequent dust visit to the sensor. Some said the lens push/pop unavoidably sucks in dust. But how does P&S gets away from this problem,( ignore the exception)??

[wda]

I'm not sure it does ignore the problem. Dust is everywhere. Small compacts generally have smaller sensors, but the risk is similar. Objectionable dust is is easy to remove in  PP.

[adan]

Not hard at all to isolate the sensor in a non-interchangeable-lens camera from acquiring dust via the lens.

Simply set up the optical design so that the rear lens element does not need to move.

And then seal the rear-element-to-sensor connection.

< ())()( > [)| |]        moving elements        fixed rear element      sensor       sealed unit

The front parts of the lens can extend and contract, and/or zoom, and/or focus all they want, and pump dust around, without any of it "visiting" the sensor. Internal dust may reduce contrast after a while, but not spots on the pictures.

I'm sure the Leica Q is set up that way - its rear-most element seems fixed in position.

See lens cross-section about 1/4 of the way down: https://www.kenrockwell.com/leica/q2.htm

Not always perfect. When I worked at the camera store, we occasionally received "sealed" P&S cameras for servicing that had visible dust shadows showing in the pictures (maybe once a year on average). They had to go back to the manufacturer for disassembly and cleaning.

Lenses themselves can be carefully "vented" so that there is only one place where air, water or dust might enter. Some of the weather-resistant Fujifilm-X zooms have that feature (a screen-covered slot for "breathing" near the lens mount) Then the rest of the lens can be completely "water/dust-tight" yet still change volume/size.

https://fujifilm-x.com/en-us/stories/weather-resistant-technology/

[Einst_Stein]

2 hours ago, adan said:

Not hard at all to isolate the sensor in a non-interchangeable-lens camera from acquiring dust via the lens.

Simply set up the optical design so that the rear lens element does not need to move.

And then seal the rear-element-to-sensor connection.

< ())()( > [)| |]        moving elements        fixed rear element      sensor       sealed unit

The front parts of the lens can extend and contract, and/or zoom, and/or focus all they want, and pump dust around, without any of it "visiting" the sensor. Internal dust may reduce contrast after a while, but not spots on the pictures.

I'm sure the Leica Q is set up that way - its rear-most element seems fixed in position.

See lens cross-section about 1/4 of the way down: https://www.kenrockwell.com/leica/q2.htm

Not always perfect. When I worked at the camera store, we occasionally received "sealed" P&S cameras for servicing that had visible dust shadows showing in the pictures (maybe once a year on average). They had to go back to the manufacturer for disassembly and cleaning.

Lenses themselves can be carefully "vented" so that there is only one place where air, water or dust might enter. Some of the weather-resistant Fujifilm-X zooms have that feature (a screen-covered slot for "breathing" near the lens mount) Then the rest of the lens can be completely "water/dust-tight" yet still change volume/size.

https://fujifilm-x.com/en-us/stories/weather-resistant-technology/

Good point !  So, if new lenses put a fixed rear element, assume a high quality optical glass, it should help. 
Or a after market rear element for protection.

Edited March 30, 2024 by Einst_Stein

[wda]

If it has a fixed sealed rear element,  how can it be modified later without dismantling it?

[Einst_Stein]

59 minutes ago, wda said:

If it has a fixed sealed rear element,  how can it be modified later without dismantling it?

Maybe fixed by screw-in?

[NigelG]

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Disassembling my Ricoh GR11 for the second time to try to deal with this(large dust spot in what is usually the “sky” part of the frame)…🙄

Edited March 30, 2024 by NigelG

[Keith (M)]

Back in my Canon DSLR days, I had the 100-400mm f4 L, know to the cognoscenti as "The Dust-Pump", given the size of the lens and its push-pull zoom action.