Experiments In Afocal Microphotography

[mikecable]

Admiral Formation--Permian--Lawton, OK

[Missourian]

Microscopes open up a whole new world.

[mikecable]

As a teacher, I was lucky to receive about four gallons of matrix from the PCS phosphate mine in Aurora, NC. And of course, as a teacher, I had to see what the material held before I turned my students loose on it. Don't worry--I'm not depriving them. I took out about a pint of material and haven't even begun to finish going through it yet.

To give an idea of scale, here is the material I photographed in a 100 mm petri dish.

Some bivalves and a gastropod.

A neat little vertebra that would benefit from photo stacking.

A shark tooth, fish tooth and fin spine?

Naturally occurring asbestos crystals?

And my favorite--a stingray barb.

[mikecable]

The Seben camera mount can be a persnickety beast. You have to wiggle and jiggle and adjust and readjust to get the field of view just right. And then it has a tendency to drift. I'm not unhappy with it--I can now get decent pictures through my scope.

But yesterday evening everything just seemed to fall into place easily--and didn't drift out of place. A few more pics of Aurora PCS mine material.

For scale--100 mm petri dish.

Some nice wee beasties.

And my favorite. Smalltoothed Sand Tiger Shark?

[mikecable]

Tonight's experiment was to try and work on a smaller level. Smaller specimens, higher magnification--trying to capture detail in terms of microns rather than millimeters.

I'm learning something about my tools. I mentioned this morning that I had better control of the Seben camera mount. I'm using a binocular microscope head, and not a trinocular head that has a vertical eyepiece. Since the eyepiece I'm using to mount the camera mount is inclined, and I'm using a fairly heavy camera, I found that gravity is my enemy. If I tilt the entire mount slightly away from myself, and more toward the vertical, before I tighten everything down, gravity works for me.

Now for the pics.

Again, this is PCS Aurora mine material from NC. This bit is somewhere between 500 and 1000 microns in diameter. As you can see, it's ruler straight with a very slight taper. Echinoid spine? It's not really clear from the photo, which is not B & W, but full color--this is comprised of what appears to be black phosphate.

Second specimen--

Again, somewhere between 500 and 1000 microns in diameter. Slightly curved, but no taper. This specimen appears to be silicate--slightly translucent. I want to try later to document this with some dark field or sub-stage lighting.

I welcome ID comments, or comments on how I might improve the photos.

[Missourian]

Nice images.... and don't be afraid to post BIGGER ones.

[mikecable]

Nice images.... and don't be afraid to post BIGGER ones.

Everything I post is big. Just a matter of perspective.

[Coco]

Hi,

I think they could be fossorial sea urchin spines (who lives in the mud).

Coco

[mikecable]

Hi,

I think they could be fossorial sea urchin spines (who lives in the mud).

Coco

I think you're right. Unless somebody offers another suggestion I'm going with echinoid spines.