fluorescence!

In the run-up to my viva I decided that the nicest way to make my totally spurious personal-use-only hard copy of my thesis would be using a £90 hole punch, so I stacked up some discount codes and bought into the Atoma disc-binding system. Obviously, when you have a £90 hole punch you bought for a single specific purpose, you fairly rapidly discover that you are in possession of a solution looking for problems.

Happily, Admin: the LRP presents no shortage of problems.

... or, more helpfully: after the first event of 2022, we decided that we could do a little bit better in terms of issue-tracking than my horrible scribbled bits of torn paper, and designed and set up a whole entire analogue ticket system based on query slips!

( Background. So much background. )

For convenience, I have taken to collating like query slips we'll probably want to refer back to during the event (the background above; lost property; found property; ...) into disc-bound booklets. Alas, "white paper someone's scribbled all over" doesn't really stand out much from The Chaos; happily, this gives me an excuse to make FLUORESCENT NOTEBOOK COVERS with the contents written on the front in BIG FRIENDLY LETTERS.

Because reasons, I had a stack of fluorescent cardstock -- pink and orange and yellow and green. The thing is, though, that Admin: the LRP has A Colour Scheme. That colour scheme is Royal Blue. Obviously, therefore, I wanted some obnoxiously loud fluorescent blue cardboard.

... I was a frankly embarrassing way into tediously unedifying search results before it occurred to me to double-check how fluorescence actually works.

To first approximation, things are colours because they absorb all the visible wavelengths of light except the one they appear to be, which they reflect back to you more-or-less unaltered. Per wikipedia:

Fluorescence is the emission of light by a substance that has absorbed light or other electromagnetic radiation. It is a form of luminescence. In most cases, the emitted light has a longer wavelength, and therefore a lower photon energy, than the absorbed radiation ... Strongly fluorescent pigments often have an unusual appearance which is often described colloquially as a "neon color" (originally "day-glo" in the late 1960s, early 1970s). This phenomenon was termed "Farbenglut" by Hermann von Helmholtz and "fluorence" by Ralph M. Evans. It is generally thought to be related to the high brightness of the color relative to what it would be as a component of white. Fluorescence shifts energy in the incident illumination from shorter wavelengths to longer (such as blue to yellow) and thus can make the fluorescent color appear brighter (more saturated) than it could possibly be by reflection alone.

... oh, I realise, belatedly. Oh. Er. Fluorescent blue is not really a thing in most contexts... because blue light is the shortest wavelength in the visible spectrum... so since fluorescence works by converting shorter-wavelength light to longer-wavelength light... fluorescent blue only really works if you've got lots of UV bouncing around the place... whiiich isn't something that happens very much in domestic indoor settings so it er isn't surprising that (i) there isn't much demand for it, and (ii) fluorescent green is the shortest-wavelength colour that's trivially available on cardstock.

And so! I have resigned myself to making do with the colours I already have available (I've been doing some clearing out of Stuff from my parents', and a giant stash of 90s kids' stationery has mostly gone on Freecycle, but a few bits of it I kept), and as consolation have a bit more of an understanding of How Colours and How Lights, and on the whole I think this is a fair trade.