I have an old, used Panasonic LX100 (Point and Shoot) that I plan to use as my main all-use video camera. I just started noticing that dust spots are visible in the image on apertures larger than about 4, and they become sharper as aperture is increased.

I have a couple of questions. First of all, would this indicate that the dust is on one of the lens elements, on the sensor, or either?

Second, if I were to have this commercially repaired, would either repair be substantially harder than the other? I'm keeping cost in mind as I might just get an ND filter to avoid using the higher apertures if the cost is too high for my practicality (at least until I save up to have the repair done).


1 Answer 1


The dust is most likely “on the sensor.” Technically, the dust is most likely on an optical filters in front of the the sensor...typically a band pass filter that blocks ultra violet and infrared red frequencies.

An ND filter is probably the lowest cost work around other than disassembly yourself.

Dust in the lens will usually not be visible because the light diffracts around it (though severe dust might cause other optical effects). To get an idea how large an obstruction can be, catadioptric or mirror lenses have a large mirror in the center of the front element which light diffracts around.

  • "Technically, the dust is most likely on an optical filters in front of the the sensor" ah yeah I learned this after posting the question. Sounds like it's on the sensor, which I'll not risk taking the camera apart myself for :) thanks!
    – Galaxy
    May 26, 2021 at 20:17

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