1 sek.....lol
real testng is 100 to 1000 times faster
"Brightness:
Brightness values are measured during
a current pulse of typically
10 ms, with a tolerance
of +/- 7%.
Forward Voltage:
The Forward voltage is measured
during a current pulse duration of typically
1 ms with
a tolerance of ± 0.05V
and here is one of the beast that can do this...
http://sine.ni.com/nips/cds/view/p/lang/en/nid/212038#
the why and whats...
View attachment 3730304
http://sine.ni.com/np/app/main/p/ap/mi/lang/en/pg/1/sn/n17:mi,n21:7037/fmid/8839/
nice. what a bargain
http://sine.ni.com/nips/cds/view/p/lang/en/nid/212038
we can get all theoretical but i think guod demonstrates that anybody on this board who thinks they are taking a real pulse measurement is prob. mistaken.
take my data or leave it, im just a guy measuring real light output with a real heatsink under reasonably controlled real conditions, at steady state, which is how we all operate our lights
you can take mfr data (which NEVER jives with other companies' data), and yes every chip has different thermal characteristics. efficiency aside at a given wattage, when buying cobs i personally dont care about mfr data, i care about what a cree @ 50W looks like vs a citi or vero at 50W on the exact same heat sink in the exact same environment. if a chip has poor thermal characteristics its gonna show itself
at the end of the day its electricity in and photons out... thats my biggest concern. not how well cree and citizen and bridgelux are each individually following a NIST protocol so as to make their data comparable to other mfrs.. pulse data by definition discounts most if not all of a chips thermal transfer properties, which is kind of a big deal for real world applications
