Before we do anything hasty and dismantle the big intimidator, that venerable harbinger of particle-trapping heritage, I obtained some images of the focal point.

Here is the setup:

Here are the images. This is different than what I have seen before. I think the triangular shapes coming out both ways are coma effects, possibly caused by the z-lens being tilted. Another factor is probably the thickness and sherical-ness of the first lens, which I think is a 50mm or 75mm lens.

Slower version