Self-experiment on whether screen-tinting software such as Redshift/f.lux affect sleep times and sleep quality; Redshift lets me sleep earlier but doesn’t improve sleep quality.
I ran a randomized experiment with a free program (Redshift) which reddens screens at night to avoid tampering with melatonin secretion & the sleep from 2012–201311ya11ya, measuring sleep changes with my Zeo. With 533 days of data, the main result is that Redshift causes me to go to sleep half an hour earlier but otherwise does not improve sleep quality.