I am still testing my new micro flash and have noticed that it also emits a strong light in the IR range. This leads to a loss of resolution, so a cut filter must be used. The original Olympus BX lamp house has one built in. I am familiar with the B+W UV/IR blocking filter – 486 MRC – from macro photography. At 43 mm, it fits perfectly into the BX filter holder between the condenser and the light exit above the field diaphragm. To see the surface of the test radiolarian better, I used an old darkroom technique: solarization, which I simulated in Photoshop with control layers.
The radiolarian was photographed on the Olympus BX-60, UApo340 NA1.30 oil on both sides (condenser and lens), PE 2.5 Nikon Z9, micro flash, and the cut filter described above. Modeling light switched off.
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