u/Dangerous-Billy

Banana for scale.
These are some scarf rings I made, mainly for practice getting the joints right. They are made of #8 ga copper wire, electroplated with tin (I've given up silver for Lent). To they naked eye, the tumbled rings look flawlessly shiny. Even tin takes on a nice gleam. But when I photograph them, flaws and mottling appears (2nd photo).
Is there a reason this happens? (It happens with silver, too.) Is there a way to photograph shiny stuff without this effect?

From the lost archives: A notebook page from my analytical chemistry class, 1963. Some of us knew slide rules, but they only did barely 3 sig figs. The grizzled old prof demanded we use log tables, and we had to show the work. Frankly, it would have been easier to do the long division.

This is why, 35 years later, I called my own analytical course "bootcamp for chemists". Laptops were still rare, but everyone had scientific calculators. No logs.

Seeing as how I'm often harping on safety in the lab, I thought I'd show a snippet from a paper I published in 1979, in the waning days of cowboy chemistry.

This was before the incident where I blew dinitrophenylhydrazine all over the inside of the same hood.

A suspect carcinogen/teratogen warning on titanium seems a tad extreme. Do I handle them with three foot tongs, or what?

This is a 1974 photo from my first lab, with Canada Fisheries in Newfoundland, Canada. We were measuring arsenic in water, fish tissue, sediments, etc, by distillation of arsine into a solution of diethyldithiocarbamate in pyridine. The color was measured at 520 nm. We could detect 0.3 +/- 0.1 micrograms. The only interference was from antimony (which max'd at 500 nm). I adapted the method from one in Standard Methods for Water and Wastewater.

The hood was homemade and drew away the large amounts of hydrogen produced, plus the pyridine stink.

People said to us, why didn't you use AA or some other fancy instrumental method? The reasons were (a) this method was far more sensitive than FAA, and ICP was not a thing yet, and (b) we could turn over three racks of 20 samples per day, or 60 samples, without breathing hard, much faster than we could prepare samples.