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Sleep &
circadian
Research-backed insights on blue light, screen flicker, and circadian health.
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Sleep & circadian
Delayed Sleep Phase and Your Mac Screen at Night
Delayed sleep phase needs a clinician. What the one glasses trial in DSPD patients found, and an untested warmth example for a night owl's Mac screen.
8 min read
Sleep & circadian
Screen Time Before Bed: A Mac Evening Routine by Kelvin
Screen time before bed, done better: what the eReader and room-light studies found, and a two-hour Mac routine with the warmth to set at each step.
8 min read
Sleep & circadian
Shift Work Sleep and Your Mac Screen: A Kelvin Guide
Shift work sleep disorder needs a clinician. Your Mac screen needs a plan: the warmth to set before your sleep window on nights, lates and rotating shifts.
8 min read
Sleep & circadian
Best Circadian Health Apps in 2026: 9 Tools That Actually Work
Nine circadian apps for 2026 across display filters, sleep trackers, light therapy and chronobiology, each checked against the research behind it.
14 min readSleep & circadian
Blue Light and Sleep: What Your Mac Display Does to You
Evening screen light suppresses melatonin and pushes your body clock later. What the research shows, and how far a Mac display can be shifted.
10 min read
Sleep & circadian
Red Screen Filter for Mac: Deep Red
Night Shift stops at warm white and f.lux's regular warmth settings at deep orange. Here is what deep red looks like on a Mac and how to set it up.
10 min read