freezeland2
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Any thoughts on my post #77
Any thoughts on my post #77Honestly run the light at max if possible and adjust height would be the best way to go.
I dont see a need for any such device. It doesn’t tell you what a plant can handle and every single grow and genetic is different.
They are meant to record readings that can be duplicated later on. You can do that with any meter. Its just not as universally accurate when giving data to someone else
Not sure what you are circling i am talking about the difference in this area.View attachment 1256222
their chart is a little confusing, but the actual comparison line is almost 100% in line with the non-dimmed light :)
Better picture:
View attachment 1256224
Just lower a few inches1st pic 600w hps at 26" with open reflector. 2nd 600rspec. The hps looks more natural to me. May just be me, under the Rspec the nodes are stacked decent but the new growth looks thin compared to hps
Thats exactly the point i was making the meter is great for record purpose’s. Because every grow room and genetic is different. The meter allows a reference but it cannot tell you how much light your plants need. You can do the same with a cheap meter so long as it’s consistent.I have been resisting replying to this thread as I too have an Apogee. I use it everyday and have 3 plants beginning flowering. They are two different strains so I have them in two separate spaces. What I find useful with my apogee and has been very educational is the correlation between the response to lighting and vpd. There are days when the plants want more light, and other days less light. And vpd plays a huge role in that. I have been recording my ppfd readings and vpd when I have the leafs presenting flat. When I see or intentionally make changes in vpd I have recorded readings so I know exactly what intensity I need to set the light at. It’s amazing to watch the plants respond. Before it was all guess work, not now.
It is in an overall sense but when you look at the impacts a very tiny amount of UV and infared make in plant photomorphology its not as minuscule as led to believe. Especially when a 5% uvb can stress plants right the fuck out as seen when we move indoor plant’s outside. They need to be hardened off first.The way HLG does there dimmers and driver programing is very flat concerning spectrum. And there is no magic sauce being hidden from anybody or the light spectrum with the last two dimmer settings. If you map out your watts draw and have a EPAR MQ-610 and a MQ-500 the 610 will show a higher PPFD dimmers wide open because it's sensing some of the UV and the scant amount of far red the 500 cant measure. With my 260 rspecs and 350r's I have tested them with a spectrum tool much like MIGRO has used in his video's. And a 500 and my 610. To replicate HLG's spectrum chart one has to be wide open on the dimmers and as you bring the dimmers down you lose a very small bit on the UV and far red and a bit on your total curve. But in the big picture it's only maybe 3% to 4% between max settings and the lowest setting. So the over all spectrum change is very very little over all between idle and max power. It's really miniscule. It's funny to see how a 610 will measure the UV and far red better than the 500. Wide open the 610 will read 20 or maybe 30 higher on the PPFD and as you bring the dimmers back down the two meters start reading closer to the same because the edge of the UV and far red the 610 EPAR can see starts going away.
The UV we are losing is "A" as expressed in there own spectrum charts in "nm" same with the Red. When hardening plants for outdoor the UVA in most cases isn't as much as a supplemental UVA light can do. And what gets them is UVB and that can be a real sombitch. And few if any grow lights really put out any real amount of UVB because it destroys leds,,,, very hard for leds to stay whole and put out meaningful UVB in the long run. And the amount of UVA/B some of our older tech puts out like MH/CMH UV is what truly wears them out. It really gets to be a very complex conversation that functions on basic light spectrum and tech thats been around as long as electricity.It is in an overall sense but when you look at the impacts a very tiny amount of UV and infared make in plant photomorphology its not as minuscule as led to believe. Especially when a 5% uvb can stress plants right the fuck out as seen when we move indoor plant’s outside. They need to be hardened off first.
So while i agree in theory overall not a big deal but in practice it can make a difference
Yes effective and efficient UVB come from fluorescent tubes.The UV we are losing is "A" as expressed in there own spectrum charts in "nm" same with the Red. When hardening plants for outdoor the UVA in most cases isn't as much as a supplemental UVA light can do. And what gets them is UVB and that can be a real sombitch. And few if any grow lights really put out any real amount of UVB because it destroys leds,,,, very hard for leds to stay whole and put out meaningful UVB in the long run. And the amount of UVA/B some of our older tech puts out like MH/CMH UV is what truly wears them out. It really gets to be a very complex conversation that functions on basic light spectrum and tech thats been around as long as electricity.
WowA really good read on the subject.
Frontiers | An Update on Plant Photobiology and Implications for Cannabis Production
This review presents recent developments in plant photobiology and lighting systems for horticultural crops, as well as potential applications for cannabis (...www.frontiersin.org
At above certain ratiosWow
In cannabis plants, THC levels are negatively affected by the presence of green light
Magagnini, G., Grassi, G., and Kotiranta, S. (2018). The effect of light spectrum on the morphology and cannabinoid content of Cannabis sativa L. Med. Cannabis Cannabinoids 1, 19–27. doi: 10.1159/000489030
Tons of interesting stuff in that study.
Take another look, that was a cut and paste from the study, not me typing that.No no no… at certain ratios only
So green is actually the most efficient photosynthetically at high intensity contrary to popular belief.Take another look, that was a cut and paste from the study, not me typing that.
Green kinda baffles me to be honest. I don't feel like I have my arms wrapped around that one yet. Conflicting info everywhere unless you really dig in on the details.
Yeah man, I learned that from you hereSo green is actually the most efficient photosynthetically at high intensity contrary to popular belief.
@Moe.Red lol you have so much to play with now
When I worked at a hospital we did a study on UV lighting. In the old days it was standard to bring in special UV lighting for patience care and many rooms had dedicated UV fixtures mounted up high and indirect. It was used to kill some germs and such. What we found out is the UV lights of any type and build available at the time were basically worthless in 30 days running 8 hour light cycles daily. Hospital spent a huge amount of money on this study done with Phillips and in house.Yes effective and efficient UVB come from fluorescent tubes.
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