After messing around for what could in fact be several years now, I have finally gotten my Vario-orthomat and my Nikon D300 to successfully "mate". It required machining a custom nikon adapter to hold the 0.32X converging lens at the appropriate distance from the DSLR focal plane, and basically replaces the 35 mm film back with the D300. It's parfocal between the oculars and the D300 to within approximately 1 micron at the objective (fast) end now. I will tweak the adapter very slightly to bring it completely in. I apologize in advance for the badly done white balance etc., but I was sufficiently excited that I just snapped a few shots of a pacific sturgeon that I had microtomed and stained but couldn't get a decent picture of using my older camera (pixels were too large for the 40X / 1.3 NA). These shots were taken using the D300 in bulb mode with the Vario-orthomat as the shutter (the PMT in my unit is not too well calibrated, had to dial the exposure in by hand with a few iterations). You can also hold the Vario's shutter open permanently and use the DSLR (with or without flash), but the Vario's shutter is effectively vibration free.
Optical conditions: Orthoplan with BF (Kohler) illumination, 40X/1.3 NPL Fluotar or 60X/1.4 SPlan Apo objective, Vario-orthomat Zoom, 0.32X adapter to D300.
Specimen is a piece of sturgeon (Acipenser transmontanum) intestine fixed in 10% AFIP buffered formalin, embedded in Polyester wax, sectioned at 5 microns, post-mordanted in Bouin's fixative and stained with Ehrlich's Hematoxylin and Gomori's trichrome stain. Nuclei (purple), muscle and collagen (green) and erythrocytes (red) and granulocyte granules (VERY red) all are visible.
I will post something in the techniques section with drawings for the adapter and more details in a few days.
--David
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