Building LED lights from facts, no theories

[knna]

BB, I dont know how old is the version, but you can find it here. Its my local forum (spanish). But I believe you can download the sheet without being registered there. Not sure actually. I uploaded it to Rapidshare some ago, but I lost the URL.

On the same forum, there is a subforum dedicated to LED growing with many journals, if you are interested (at least on pics, if you dont understand spanish).

That tone /12 of Phillips is the best UVB Ive seen, but unfortunatelly I dont find it here. Its listed on Phillips website, but no any distributor carry it

Thank you for that test report, its very complete. I think its pretty accurate, due it seems to have being performed using a good spectrorradiometer, as it not only states photometric values on a very complete way, but radiometric ones.

Not all days I have the possibility of checking the accuracy of my sheet, so I digitalized that induction lamp SPD and introduced the measured lm output of the report , 23881.5lm.

The sheet reported 81,940 Watts of output 380-780nm, while the report says 80894. Its less than 1.3% of error, which I think is excelent when data comes from a graph.

That spectrum contain 14.1 uE (PAR) on each 1000lm (or lux). So you can know the irradiance from it just multiplying by 14.1 the reading of your lightmeter (in lux) and dividing by 1000.

Now you just need to do the same with your LED's spectrum.

knna Reviewed by knna on 07-30-2009. Building LED lights from facts, no theories I was going to post this at the Perfect LED Grow Light thread, but as some of what im going to post was posted 2 years ago on the stickied thread about LEDs and people still continue developing lights from wrong ideas, i think a thread about this topic is largelly needed. The main problem is related to efficacy of spectrums. When the firsts LED experiments at Overgrow, we work on the hypothesis that blue and red light are more effective. It was an appealing hypothesis that promises large Rating: 5

[Bubbleblower]

That tone /12 of Phillips is the best UVB Ive seen, but unfortunatelly I dont find it here. Its listed on Phillips website, but no any distributor carry it

You can order them here. Shipping to Spain is â?¬ 17,44.
Here is a normalized spectrum of the lamp compared with 4 other UV sources.
UVB-leds are still VERY expensive unfortunately.