churchhaze
Well-Known Member
Even within the metric system, it's possible PPFD could be measured in units of umol*s^-1*km^-2, it's just that nobody will ever use that unit.
Oh, well the difference in my experience would be close to 33% more yield per sq/ft using 800 PPFD. The yield per par watt would be similar but for any particular space higher wattage is higher PPFD. Sorry if I was unclear, what I mean to say is that there may be no relevant increase in yield per par watt comparing 600 to 800.My main question was that if yield is not effected say on a 600PPFD or 800PPFD than what is the point of the extra light?
Im not a cheap person, but conservative. Real world results mean more to me than hypothetical numbers.
Mainly planning a Vero29 build or CXB build and wondering the yield difference if I go from 600 to 800ppfd. Seems like wasted light. I run large numbers of plants in 3 gallon coco. I pull 2lbs from 9 Blue Dream in 3 gallon Coco under Blurple. in a 3 x 3 tent.
This is true. Canopy level and veg time as well as genetics.http://www.angelfire.com/cantina/fourtwenty/yor/prodtable.htm
Some oldschool analysis, and surprisingly accurate when you compare to grow journals.
If the chart is accurate, the difference between incremental lighting steps is pretty small, but adding canopy space is very effective. Moving a 400W light from a 2x4 to a 4x4 can nearly double yield with the same electric bill.
Also makes GPW seem even sillier.
That is helpful. By how much is the question.Oh, well the difference in my experience would be close to 33% more yield per sq/ft using 800 PPFD. The yield per par watt would be similar but for any particular space higher wattage is higher PPFD. Sorry if I was unclear, what I mean to say is that there may be no relevant increase in yield per par watt comparing 600 to 800.
Jorge's link tells a different story though and I wouldn't call my test results definitive. In the case that my results are wrong, there's still some sense in higher PPFD if you want to increase yield but can't or don't want to increase the space involved. 800 PPFD in a particular area will out yield 600 for sure. We're just trying to figure out by exactly how much. The table in that link seems to have quite a bit of solid work behind it so it should be helpful.
Was no CO2 talk, but I always have CO2 especially in Veg.I may have missed it. But was CO2 mentioned in this discussion?
strains?I posted some metrics on a CXB harvest video near the end. I calculated like 650 ppfd for my 700ma setup over a 4x8. Gpw was great at that amt of light with no co2 supplementation. i don't have anything empirical to contribute at growing with cobs above 800ppfd. But I will very soon
Will have a look. Ps keep up the videos. Really great stuff.I posted some metrics on a CXB harvest video near the end. I calculated like 650 ppfd for my 700ma setup over a 4x8. Gpw was great at that amt of light with no co2 supplementation. i don't have anything empirical to contribute at growing with cobs above 800ppfd. But I will very soon
On his channel.strains?
medium?
It is a unit. Getting even PAR to the canopy. Really have no idea how you can say that.There is no such thing as 800 PPFD.... PPFD is not a unit!!
Your screen is not 1080 resolution. You don't buy 1 volume of gasoline. You don't drive 1 distance of road. It's not correct English.my Printer - dot per inch - dpi
my screen resolution pixel per inch - ppi - and the size of the screen is given in Zoll just as my car tyres
all electronic parts are in inch - fraction of
and many more...
we also deal with miles - aircrafts and ships mostly
no gallons, oz or pounds in daily use here ... thanks good
we know how to handle this
It's not a unit. umol*s^-1*m^-2 is the unit most commonly used for PPFD, and is what you all mean when you say "800 PPFD". PPFD is not the unit, it's a variable.It is a unit. Getting even PAR to the canopy. Really have no idea how you can say that.
The YOR analysis seems much more scientific than what I have done, so you can comb through the methodology and use the lumen chart to get an idea of the percentages they came up with.That is helpful. By how much is the question.