Sky Ember Journal
Notes on light, screens, and sleep
What blue light actually does
The peer-reviewed record: what evening screen light measurably changes, what blue light doesn't do, and what circadian scientists actually recommend.
The red screen trick
Why astronomers use red light, why Night Shift can't do it, and how to get a true red screen on macOS.
PWM, explained
Why some people get eye strain and headaches from dimmed screens, how to test your display in 30 seconds, and what actually helps.
Brightness and display lifespan
LM-80 lifetime data and a 100-TV aging study agree: your brightness setting is the biggest lever over how long your display stays bright and accurate.