170k (!!) lux reading from DIY LED

NeveroddoreveN · Nov 11, 2019

The measurement was taken at about 12" using the Galactica iPhone app. My fixture uses 13 cree xp-g3 LEDS (5w each) and it was turned to full power, maybe 80% the max amperage of the led.

Using lux to estimate par is crazy, and using an iPhone app to estimate lux is crazier. HOWEVER, all other measurements taken with the app are sane... My friends tank is between 4k and 15k... Sunlight is about 30k.

The takeaways are (1) don't trust a phone app for lux and (2) cree xp-3s are really, REALLY bright.

oreo54 · Nov 11, 2019

170,000 Lux is only slightly brighter than daylight (2000 PAR)..

at about 2500 "PAR"... if you are considering daylight LED's..

@ 6W (max) and 190L/watt..14,820 lumens (per CREE).. and if all that light was in a 1sq ft area you would have 159,521 LUX..
@ say 67 Lux/"PAR" unit..2380 PPFD ("PAR").

no not encouraging phone use for this stuff. Too many "issues".. though "studies" goes back and forth regarding them..

sunlight isn't 30,000K either which I assume you were implying..