hmmmmmm.Okay. Sorry for dragging this topic for way too long but I think I just need one more suggestions based on the following criteria. 4x4ft or preferably 5x5ft coverage, around 1000$, full spectrum or close to it.
Il have a look later on for any more products around that price point.
I believe UV and IR are worth the investment since it's not snake oil...or?
I understand at a deep level the photomorphological processes involved with plants and light. The study of light responses of plants has been ongoing for well over two centuries. Bruce bugbee leads the research for light and plants. His research is what i consider the material for what would be the bible on photomorphogenesis. With his research there are few questions i have that are unanswered. Infrared light has no photosynthetic capacity because of the red wall problem. In which energy wavelengths longer than 700nm cannot provide enough energy to complete the photocycle. Infrared can activate certain morphological responses, called the shade avoidance response. But there is no need when ideal morphology can be influenced by energy inside the photosynthetic bandwidth. Where far red can be useful is with flower induction, by reducing the flower induction time by activating key photoreceptors responsible for flowering. The level of intensity required to have a physical effect would need to be quite high so as to counteract the balance of PR and PFR. Far red diode technology is about half as efficienct as Red, Blue, White diodes. Which means the potential savings from shortened flower induction is heavily counteracted by its lower photon efficiency.
Ultra violet has much like infrared, poor photosynthetic response. Due to the fact that light harvesting complexes do not harness much energy with wavelengths longer than 400nm. Its also well known that ultraviolet reduces photosynthesis in plants because of its damaging effects on photosystems. There has been the notion that ultraviolet light can stimulate the production of resin and thc through stress responses. This is not the same as photomorphogenesis but through other mediators such as thigmomorphogenesis. UV-B has been shown to increase the THC concentration in cannabis, when used during the mid to late stages of flowering. However one aspect that really goes against the use of ultraviolet is its very very poor photon efficiency. With it being about as bad as incandescent. This is why california lightworks use T8 fluorescents for UV supplimentation. If you really want to be confused read my post
here about the stokes shift with light.
My articles explain the important principles between technologies.
Comparing light technologies explains what aspects of LED light technology that should be used to asses quality and performance. Such as diode model-type, wattages, equivalent wattages etc. My article on
grow light technologies also details important aspects such as efficiency, distribution, photosynthesis, photomorphology. I hoped that these articles answer most questions. Infrared and ultra violet fall under the same conclusions in my assesment on light quality in that article. However i will look at making this more clear with respect to other wavelengths such as ultra violet and far red.
About efficiency...I mean, I think I don't care about efficiency. It's not like they'll be less efficient than hps or am I mistaken? I'll gladly ditch it for flowering power.
Depends what products you are talking about. If you are referring to cheaper products like the vipar and other amazon-china lights. Yes, they are less efficient than gas discharge. For the products we have been talking about such as the cob you cited and the california lights. Then they are more efficient than gas discharge.
The only other important thing is temperature. Surely the less efficient leds don't compare to hps heat? Everyone! Forgive me for my ignorance! *seppuku* + More Options
With LED light products that are less efficient than gas discharge, they will output more heat per watt in comparison. But generally overall they put out less heat because they typically have a much lower output capacity and therfore power consumption. Comparing watt for watt they would surely put out more heat. But the key difference here is that LED fixtures can direct their heat away from the canopy with passive or active cooling. But then you can do the same with gas discharge with vented hoods. Ultimately room temperature problems would likely still be a problem if replacing like for like power consumptions. The more efficient fixtures that exceed 1.7umol per watt are the only fixtures that truely produce less heat watt for watt.
Please dont feel intimidated by my elongated response, simply stating what is and what is not did not seem to be enough for you. So i replied with extensive detail as such.
