See part 1 for some details, but basically this is all on a Diaphot with a Phase Contrast 1.25 condenser, with (non-focus) stacks of 5 images each on a Nikon D3300 APS-C sensor. Views through the Bertrand lens display how the illumination was set up for the particular version of this photo. The full frame photos are reduced 6:1 in Photoshop and the crops are 100% pixel size.
Part 2 is with the Nikon Plan 4 0.13 160/- PhL DL, so even though there is no matching PhL condenser aperture, good images can be still obtained.
First, Brightfield.
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Now, with the condenser aperture closed down, reducing the NA.
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Now, moving to the Ph1 turret position, first up is circular oblique
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And with a specific offset of the Ph1 annulus.
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Ph2 and beyond are approaching darkfield. First, we look at Ph2.
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And then Ph3.
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And of course Ph4, which is very similar to Ph3 in this case.
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What diatom comparison gallery would be complete without true darkfield?
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Another long post... I hope this is being informative to someone.
Look for the next installment - Part 3 (10x Ph1).
Mike
Nikon Diaphot TMD condenser compatibility (part 2)
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