MicrobeHunter.com Microscopy Forum

The field of light descending from my epi-illuminator is not well-centered. I would like to correct this, but the question is: How?
I don't see any obvious screws that would allow to centre it. Here is how it looks like now:




The illuminator does not bear any type designation, only a serial (Nikon 260483). I believe it's identical to this one:

Hi

In my equipment, same than yours, I had similar problem, and I found that the six radial screws of the tubes of the epi, weren´t well tigth.

I found too that you can adjust puting a shim (or two oposed) between the long cilinder of the epiiluminator and the horizotal arm of the microscope frame.

Best regards

JA

Thanks Jose, but i don't think it is that issue. I cannot make the location move by manhandling the illuminator. I think it is the mirror.

Is it the lighting that's not centered or is it the field iris? That should have screws to adjust its position.

What you see in the photo is the projection of the field iris. The lamp can be adjusted indeed. It does do a lot for the contrast, but nothing to the positioning.

The cause was this: in the exit *) of the illuminator sits a black tube that separates the bright field light path from the dark field light path. It has three tiny attachment points which make it vulnerable to breaking, when the illuminator is placed flat on the table top. Mine had come off and I had it replaced by a 3D-printed tube with three projections to centre it and hold it in place by friction. However, I hadn't noticed it could hingle on these projections, wobbling to and fro round a horizontal axis. I would put it straight, but when attaching the illuminator to the microscope, it easily got banged oblique again. That made the light shine off-axis.




*) I don't know how to designate that technically; it's the part pointing down towards the objective...

I too have this problem. I've completely dissembled my illuminator, cleaned it, and reassembled it with the offset in exactly the same place. Aaaaaargh!