Coffee trouble in IR

[Andy Perrin]

This area is for infrared and ultraviolet "experiences" and this was certainly an experience, albeit not a pleasant one. This morning I went to the café to get some coffee, added some soy milk, and carried it home. I set it on the counter to cool a little and came back a few minutes later to find it in the state you see below. Apparently I got the very bottom of the container of soy milk.

 

Photos are with the Hoya R72 infrared (for maximum visibility in the coffee while retaining some color). No channel swap (this is RGB order) because I liked the blue color. Lens was the Asahi Super-Takumar 50mm/F1.4.

 

Indirect sunshine through window, F1.4 1/125" ISO800

 

With a flashlight, F8 1/200" ISO400

[Hornblende]

Fantastic!

 

Bottom pic looks like a chemical precipitation in copper sulfate.

[Andy Perrin]

Hornblende, it's probably looking that way for similar reasons. You have small insoluble colloidal particles in both cases, and they tend to form aggregates for certain pH values and amounts of electrolytes. It's in the center probably because of the convection pattern in the coffee. Hot coffee rises along the edges, cools, and sinks in the middle. (I have a FLIR thermal camera and I've imaged the coffee before.)