Hello everyone,
Here's a couple of my latest results using 365nm light to improve resolution of brightfield diatom images. Both images are focus stacks, captured with an Olympus UPlanSAPO 100/1.4 objective direct projecting onto the sensor of a Sony A7riv (modified for full-spectrum imaging).
Happy days! ;D ;D
Monopsia mammosa PS4 100x UV-2K.jpg
Kittonia-PS4-100x-UV-2K.jpg
Note: the inset in the Kittonia image was cut from the original full-sized image then pasted into the downsized (2k) image. So it represents a 100%, pixel-for-pixel copy of the original captured resolution.
Cheers
Beats
Hallo Beats,
wowh, das ist einfach eine super Auflösung. Sauber gestackt, dickes Kompliment!
Danke für's Zeigen.
Gruß
Peter
That blew my socks off Beats, thanks for that.
René
Absolutely impressive
Gerhard
Really spectacular Beats!
Bill
Dear Steve,
You've really pushed the boundaries – absolutely fascinating!
best
anne
Hi Steve,
just mind-blowing, fantastic!
Thanks for your comments everyone. Much appreciated.
I started down this UV path purely to improve resolution of tiny details or closely spaced pores that can't be resolved with white light, but I soon discovered UV offers other benefits too. Shallower DoF and different transmission behaviour made focus stacking work better in general with less random mixing of overlapping details. Fine details nearest the objective tend to dominate over detail deeper in the stack, which looks more natural. Also, mountant RI is higher at shorter wavelengths which increases contrast. I mount in Darax which is reported to be RI 1.7+ (as measured at the sodium D-line with a wavelength of ~589nm). I'm pretty sure RI approaches or even exceeds 1.8 with 365nm UV. Lovely!
I expected to use UV rarely, when I found diatoms with tiny details that couldn't be resolved with "normal" lighting. I was very wrong about that! UV improves the rendering of larger, coarser diatoms too. So much so, I simply can't be satisfied with the results I get under "normal" lighting anymore. That was unexpected, but I'll live with it... ;D
Here's a couple of examples demonstrating what I mean. These are inside and outside views of Triceratium favus, also from Oamaru. The valves are from two different diatoms but they're about the same size. Most of the details shown are easily resolved in white light, but it simply doesn't look anywhere near as nice - in my view.
Triceratium favus, inside view
Triceratium-inside--2K.jpg
Triceratium favus, outside view
Triceratium-outside--2K.jpg
Anyway, thanks again for looking and for your encouraging comments.
Cheers
Beats
Hi Beats,
I am officially impressed. It amazes me what details can be seen in an image from a "light" microscope.
Regards,
Michael
Amazing work Steve, really inspiring!
The tones on the Monopsia make it almost look like a pencil drawing, but with exquisite detail - really nice. Is it simply brightfield? Do you stop the condenser down at all?
Thanks Michael. I'm amazed too. Knowing it's optically possible in theory is very different to actually seeing it (at last).
Thanks Adam. Yes, brightfield, because contrast enhancing techniques (like phase, DIC, COL, etc) all reduce the max resolution (NA) available while brightfield doesn't. The condenser is wide open at 1.4 too. If it were stopped down, the objective wouldn't achieve its maximum resolution because condenser NA must be >= objective NA to get that. I also expose hard to the right to get the initial images as bright as possible with more values covering the captured tonal range - giving more leeway for contrast stretching without getting the dreaded "over-processed" look. Finally, I do no sharpening, except for an *extremely* light "sharpen for screen" when exporting down-sampled jpegs for posting.
Cheers
Beats
wow, sind ganz tolle Aufnahmen - weiter so.
Viele Grüße aus
Heidenheim
Reiner
Hi Beats
Those are breathtaking photos—congratulations!!!
I'am, dreaming from a solution of taking photos of Ditomee too, using UV lighting to higher the resolution.
I started with a black-and-white UV industry camera and illuminated the subject from below the objektct with a 365-nm UV LED; right now, I'm considering using 365-nm incident light to get the other light direction too.
My plan is to get a Nikon body modivied for full spectrum use.
Allow me one question, what light direction are you using for your absolute amazing photos?
Many thanks & regards
Gerhard
Zitat von: Rawfoto in August 12, 2026, 16:37:57 NACHMITTAGS...
Allow me one question, what light direction are you using for your absolute amazing photos?
Thanks Gerhard,
Simple brightfield illumination, transmitted through the diatoms from underneath, then on up into the objective.
Cheers
Beats
Many thanks for your quick response Beats
Regards
Gerhard
Hi Steve,
You've pushed the microscope to its absolute limit. The difference in resolution between your images and those from the SEM is almost imperceptible. Congratulations!!
Bernd