When using a camera to record video with my Nikon E600 microscope via the trinocular port, I see a dust spot on my camera that does not move when I move the stage.
At first I thought it must be on the camera sensor, so I cleaned the sensor using Eclipse cleaning fluid and sensor swabs. I couldn't get it perfectly clean, but it's pretty good now, especially away from the edges of the sensor frame. I determine this by photographing a white sheet of paper with the lens aperture at f32 and zooming in to view the dust specs.
However, the dust speck in video persists.
It shows up as a blob of darkness when using my 20x objective. It becomes more defined in my 40x objective, and it's almost sharp when using my 60x objective. This leads me to conclude it's not a dust speck on the objectives.
Things I've tried:
- I've blown dust off the mirrors (that I can access) in my Y-IDP attachment.
I've cleaned the top of my PLI 2.5x lens, but rotating that lens does not change the position of the dust speck, so that's not it.
I've cleaned the top of my Abbe condenser lens that tilts.
I've cleaned the top of my Abbe condenser lens that is right above the aperture.
I've blown dust off the underside of the Abbe condensor lens with the aperture.
I've cleaned the top of my light emitter lens at the base of the microscope.
UPDATE: example footage showing problem
before cleaning camera sensor:
after cleaning camera sensor:
UPDATE2: Just read that if I rotate the camera and the dust spot moves, it's not on the camera. Tried that. Dust spot moves. So camera is thoroughly ruled out as the source of the dust spot.
- I inserted and removed all three filters. No change in the spot.
I rotated the condenser top lens, no change.
I moved the condenser using the positioning screws. No change.
I shifted the Y-IDP mirror and the spot moved a little, but not a lot before the image changed. This is a possibility, but I think it's not the culprit.
I rotated the lamp house slightly. No change.
I can't figure out how to remove the field lens on the e600 microscope.
Looks like there might be three screws on top and a circular spring that hold it in place? But I think I would need to remove the turret and stage in order to do that.
Also I found this document which describes removing the bottom: https://www.nano-dyne.com/wp-content/up ... ctions.pdf