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Monthly Squares

January Squares: Polarised-light

This is my day 23 contribution to Becky’s January Squares: Light photo challenge and another fake, hyphenated word.

These are Sodium Thiosulfate crystals photographed through a microscope using polarised light. I should also note that I edited the text twice, changing the s in polarised to a z and then back to s. I’m a Brit and the photo was taken in England so it’s s.

January Squares: Polarised-light

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Monthly Squares

October Squares: Fingerprint Lines

This is my contribution to day eight of Becky’s October Squares: Lines photo challenge.

Lines in sodium thiosulfate crystals formed by my finger checking to see if the solution had crystallized. Taken using a microscope and polarized light.

October Squares: Crystal Lines

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Archives

Polarized light photomicroscopy.

In the early 1980s I was running the photo department at a scientific research establishment. This involved a wide variety photo techniques to record a range of subjects.

However, polarized light photomicroscopy wasn’t used for anything work related. Having seen the results of other people I decided to investigate the technique. In those days that meant researching in literature rather than simply Googling as you would these days.

Now I will admit that I am writing this from memory, I have googled the subject and what I have found matches my memories of the technique.

I applied drops of a Sodium Thiosulfate solution to some microscope slides and left the solution to evaporate so that crystals would form.

I mounted a polarizing filter between the light source of the microscope and the slide stage. Once the Sodium Thiosulfate had crystallized I put one of the microscope slides on the stage and put a second polarizing filter above the slide. When you rotated one of the polarizing filters the colour of the crystals changed.

The first photo shows what I found to be a fairly typical example of the crystals.

polarized light microscopy

This photo shows small patches of colour against a mostly dark background. I’m guessing that this is a result of the orientation of the polarizing filters.

polarized light microscopy

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Weekly Photo Challenge

Lines of a fingerprint.

The Daily Post Weekly Photo Challenge is Lines.

The photo shows two overlapping fingerprints in sodium thiosulfate which has crystallized. The crystals were photographed through a microscope using polarized light.

Sodium thiosulfate is used as a photographic fixer in the darkroom as silver halide dissolves in it. Commonly known as Hypo in the days of the black and white darkroom.

A fingerprint in sodium thiosulfate.