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f.luxometer: measuring the 6500K-iPhone6
Melanopic lux = 207
Chromaticity = 0.301, 0.308
CCT = 7535K
Phase shift = 81.1% as bright as daylight
Photopic lux = 212 lux
Measured with a PR655
Melanopic lux describes how the melanopsin-containing cells in your retina react to light. These cells provide the major input to the circadian pacemaker at high light levels. At lower levels, and when things are changing, the cones appear to provide an important part of the response. For melanopic quantities, values below 5 m-lux have little effect in shifting your circadian phase, and more than about 500 m-lux is expected to saturate the melanopic response. [Lucas 2014, Gooley 2010]
Your body has a non-linear "dose-response" to light. This graph shows you how light of various intensities translate to a shift in your circadian timing. When you see light in the morning, it makes your day shorter, and when you see bright light at night, you stay up later. Phase shift shows how much you can move your body clock in just one night if you see it for long enough (a few hours) at exactly the right time of day, typically before bed. Also, you can see how the light compares to being outdoors on a sunny day, which can shift your body's internal clock by up to 3 hours. This is how your body adjusts its clock when traveling to another timezone. To find this number, we're using a best fit from several published studies, with subjects who viewed light exposures ranging from 90 minutes to 6 hours.