Sawfish tooth with a Zeiss Plan 1.6-5x zoom microscope objective

Today’s post shows a tooth of a sawfish imaged using an interesting microscope objective – a Zeiss Plan 1.6-5x zoom objective. This objective can be adjusted to give magnifications from 1.6x to 5.0x using a rotating collar. I’m sharing this as I have seen virtually nothing on this objective online.

In my microscope (a modified Olympus BHB), I couldn’t get the stage low enough to get 1.6x (the lower the magnification the longer the working distance), however I was able to get to about 1.7x. Here’s a set of images of a section of a tooth from a sawfish between 1.7x(ish) and 5.0x. They have been left at the full frame from the camera (a monochrome converted Nikon d850), and simple brightfield illumination was used.

Sawfish tooth, approx 1.7x
Sawfish tooth, 2.0x
Sawfish tooth, 2.5x
Sawfish tooth, 3.2x
Sawfish tooth, 4.0x
Sawfish tooth, 5.0x

And a picture of the slide (no makers name).

Sawfish tooth slide

Overall, a nice performance. Not the highest NA for a given magnification (at 5x this is 0.1, vs my Nikon 4x Plan Apo which is 0.2), however a very versatile lens.

Here’s some images of the objective, and the entry from a Zeiss catalogue to provide some more information.

1971, p57, Zeiss optical systems catalogue

As always, thanks for reading, and if you’d like to know more about my work I can be reached here.