Good luck og
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This quiz was harder than I thought…
First question: 164 out of 212 voted correctly that in a horticultural industry, PAR (short for Photosynthetically active radiation) is the go-to unit (or term) to measure.
Second question: 106 out of 211 voted correctly that DLI (short for Daily light integral) is the calculation that takes days into account.
For more reading about the subject I’d recommend to study great topic from @Northern_Loki - Lighting Spectral Data.
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It actually made some seasoned guys do research to learn a little… I was one of them 
YAY!!! Research and learning pays off, now if I can just get lucky lol
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and OF COURSE that’s the one I answered the questions ripped and totally screwed up on answer #2
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I must have done the same thing. Cuz my name is not on the list of entries.
Sh!t.
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I also used my phone.
Rule #1 of Pigeonman’s typing errors: Don’t do anything important using your phone.
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I just got a complaint from a member that his name is missing and he answered correctly…
I reminded him that he had also needed to post in the topic…
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I read several articles and they explained the difference. My answer was what they said was right. But, it was wrong. 
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Where in the giveaway thread does it say what the correct answer is? Is it just the one under the pie chart that is listed first?
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I’m not complaining. I was just saying. I stay medicated pretty much from noon till bedtime. I was probly pretty wasted when I answered. Not complaining.
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I saw it on there yesterday I am sure. I don’t see it now.
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Just found it. Thanks
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I’m guessing you might be referring to the DLI question which is where some folk seemed to have missed the 24 hour period portion.
PPFD is umol/second/m2. That would be number of photons per second over 1 square meter.
DLI (daily light integral) is a measure of the number of mols of photons integrated over a day. Notice that this is measured in mols while PPFD is generally umols. The difference in the number of delivered photons between the two units is 1,000,000 times (u = 10-6) as you are integrating the light delivery over the entire day.
You’d typically see this expressed as DLI = 32, as an example, which is 32 mols / day of photons averaged over a 24 hours period. Or, if we were to convert this back into PPFD, it would be:
32 (mols per day) / (86400 seconds per day) = 0.00037 mols / s / m2 = 370 umols / s / m2 as averaged across a 24 hours period.
But, that’s not all. If your lights are on for 12 hours, you can calculate the original PPFD of the lamp. In this example (24 hours in a day) / (12 hours lights on) = 2.
In this way, the fixture used in the DLI=32 example with 12 hours on, has a PPFD of (2) (370) = 740 umols / s / m2.
Conversely, you can calculate the DLI from what you know about your fixture. For instance, if you measure a PPFD of 800 umol/second/m2 and your lights are on for 8 hours a day, the DLI is 800 * 86400 * (8/24) = 23,040,000 umol/second/m2 = DLI = 23.
Hope that helps, it was tricky if you hadn’t seen this metric before.
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I especially liked that you blocked the post from a cursor highlight/copy for a simple Google search. People had to actually know the answer, or put a little effort into finding it.
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I did the research and still got it wrong. Just confirms you can’t believe every thing you read on the internet
I go into these knowing I won’t win so I just have fun playing along. The best part is watching how the winners react. 
I was referring to the first one But, you are correct on the second also. Needed to read the question better.
The silver lining, I learned something today. So, it is a good day. 
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I read posts and googled, found a variety of answers. That made it tough, it wasn’t like everybody had the exact same definition / explanation, and some were out in left field compared to the majority.
It took a fair amount of digging to be certain of my answer, and even then I wasnt 100% certain till it was revealed.
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I guess I missed the trick question, too. Damn, it’s the one thing I really wanted to have a chance at. Not sure I like this sort of protocol. It seems to give the advantage to the people who have already owned an LED light. Oh well, good luck to all of the smart people! Google didn’t work for me, lol.
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I dont see my plus 1 yet (supporter)?! hope I made it in time