I wish it was just blah blah blah. When I first came to Afn how ever long ago 1.5 years roughly I had already done quite a bit of growing with cobs. Not only growing but smaller commercial scale growing 20-40 plants. I have also grown photos with hps prior to autos with cobs. Basically I did follow the 50 watts per square foot rule with photos under hps also while implementing max co2. So back to when I joined... It was a shit show to put it lightly. Everyone was using 3w led panels or hps. I pushed cobs, explained cobs and proved that cobs were by far superior. The majority thought I was nuts with this new tech. People didn’t understand that wattage was a measurement of energy consumption and not light. There is still plenty that still don’t understand it. What happened was as cobs gained popularity and the grows kept piling in before people considered them. Now I’d say the majority uses cobs and the results speak for themselves. If you own a quality par meter or can calculate the correction formulas needed you can see first hand that 50 cob watts has a nearly identical ppfd as 140 watts of hps. Not ppf-total light emitted but ppfd the important number that measures light at the canopy. So a question is what light source do you figure when filling a room at 50 watts per square foot?
Secondly the daily light integral (dli) is not a fictitious made up term. It is the number of photons hitting the plants over a 24 hour period of time. If growing photos you flower for 12 hours a day. If growing autos you flower for 18-24 hours a day. If you multiply 12x50 that’s half of 25x50. That’s the basics behind the main reason I say 50 watts per square foot is inaccurate with autos. If you were to have 50 watts per square foot over photos while using hps that’s more like 20 watts per square foot with cobs to equal the same dli with cobs at 24 hours. Now the blah blah part. My opinion is that even 20 watts per square foot while good can still be reduced. No science but proof I have personally seen in my own grows. Grow after grow. There are very few soil grows with autos that I have seen here that can compare. Not trying to sound like an ass. How I stumbled across this was while growing autos under 50 watts per square foot I always had burnt up plants while the plants or branches near the edges were much fuller and better looking quality wise. I reduced the light till I saw spindly plants and increased it. No one has to agree with me on this but I do see much better healthier plants with less light.
@Rifleman @slowandeasy are two other growers off the top of my head that I have seen pull epic plants with what most would consider not enough light. It’s all good. How we do better is by experimenting, autos are a perfect example. Most growers laugh at autos, some laugh at 11 watts per square foot. But we push on and try our best. I am actually hurting myself by saying all of this as I sell lights. Sure pile them in.. I’d rather save someone money on lights and their power bill than sell someone something they don’t need.
I hope this helps clarify some things that I explain on a regular basis in my own section. Some is blah blah and some is science.
https://gpnmag.com/article/daily-light-integral-defined/
@MassMom in sorry to blow up your thread.
