Oil? spots on sensor

[JohnReid]

My D500 is only a few weeks old and I have multiple spots showing up. All my shooting is in a microscope facility with filtered air, the camera is mounted on a copy stand facing down, so I find it hard to see how dust could accumulate so fast. My local dealer looked at it and thought they looked like oil spots, rather than dust. Has anyone seen or heard of a similar problem?

I am having the same issue on my D7500. I have a feeling that there is oil coming off the shutter actuation. Can anyone out there confirm?

 

[bikeit]

Anyone know if its ok to use swabs 24mm wide to clean the sensor on the D500?

 

[sharp shooter]

They are not oil spots or dust spots.
They are 'Stacking Worms' (or some similar name) - caused by your stacking software.
To confirm, take a photo of a clear sky at f16 - all will be well.
Regards
Mike