Great answer man.
so my fixture is 7 (5000k),3 (4000k)24 watt Cobs CRI97 SEOUL SUNLIKE SAWS1566A on elg240c700
3pcs 10watt in a middle row 4000k Cri97 Seoul Sunlike cobs SAWS1056A
3pcs 10watt 4000k Cri95 PROLIGHT OPTO cobs on elg150c500
On same driver I run also a 3 strips by six diodes with 5uv-a, 10 royal blue, and 3 840nm(read somewhere about photosyntes F)
all they PROLIGHT OPTO
And a 40 pcs divided to 4 strips by 10 pcs of 660nm monos( PK2N-4LME-HSD PROLIGHT I'll run them on maybe half power on a elg150c1050)data says they are 410mw at 350ma,710mw at 700ma, 1000mw at 1050ma.
And a 2pcs of 370nm on 700ma gives me a 750mw each.
This fixture looks enough far red I think till daylight works for stretch.
Thanx.sorry for my English
Hmm! I see not a single diode in far-red/730nm in your discribtion. Your CRI97 COB's contain already a lot of far-red, so during the day it should be enough. But your spectrum has a lot of blue (5k COB's) and UVA wavelength in its spectrum which works against and cause less stretch. The best way would be to switch them(5k COB's and the UVA diodes) off while stretching (1-3 BW) and switch them back on when internodes are long enough to suit your needs.
The other thing is you have not a single far-red/730nm diode which you could use separately.
For a far-red based flower trigger(siutable for your area) you need ~4-6 well distributed far-red diodes in 730nm on it's own 5w driver. An you need a separate timer to switch it on and off.
I'm using 6 Cree XP-E/730nm/601bin(275mW/@350mA), a cheap 300mA e3ay driver and a Sonoff timer.
840 and 930nm is called infra red and does nothing to plants except that it warms up the leaves and the environment. I would remove them because they increase only the leaf temps which means you either need better ventilation or have to dimm the light down to get the leaf temps where you want it(~27-28°C).
Only far red/730nm is known therefor that can switch phytochrome far-red from its inactive to its active state in just a few seconds.(or was it vice versa?)
This means a plant getting far-red wavelength at the end of the day will immediately switch into "night/recovery mode". Without far-red this takes up to 2h!
This 2h can be used in different ways. You can for instance extend the day length by up to 2 hours(14/10h) without fear the plants switch back to the vegetative state. The other possibility would be to leave it at 12/12h and thus shorten the maturation because they get almost 2 extra night/recovery hours every day.
Plants use the energy stored during the day to carry out different processes during the night. With far-red/730nm EOD(end of day) treatment, they can do this for 2 hours longer which in the end results in them maturing about a week faster.
A flower trigger is usually used for up to 10-20minutes per day(5+5 mins - 10+10mins). It is switched on 5 mins before lights out and its switched off 5mins later. You can vary the timings to your needs. More far-red when main light is off means you will see more stretch and this way you can influence the stretch within a certain range. With 2+2 minutes you probably do not see much stretching, with 10+10 minutes you could probably double the final height.
So all you need is a few far-red/730nm diodes(Prolight has good ones too, no need to use expensive Cree/Osram's), a small 300mA/1,50$ driver(the white ones for 3-5x 1w diodes) and a 5$ Sonoff timer, maybe ~10-20 bucks or so.. These cheap drivers run anyway only a few minutes per day and that's why I did not have to replace a single one because of a defect to date.