new bridgelux model? VESTA® 90CRI, 130lm/W

[unkle_psycho]

So I found a little info on the matter. 30min well spent.

It seems that blue light scatters more in the atmosphere, and as the light travels further through the atmosphere at sunrise and sunset, it filters out more blue.

Clear daylight is 5500k and sunrise/ sunset is 3200k. Overcast cloudy weather is around 7000k.

[LivingLight]

Guys just keep in mind that color temperature isn't representative of the far-red amount in the spectrum.
the sunset 3200k got a huge ton of far-red, if you consider using such a spectrum you are gonna get a very stretchy plant.
The problem remains the same for the 5000k daylight from sun, it got a lot of blue but also a fcking ton of far-red balancing some of the blue effects.

What you gotta consider is the color shift during the day, but if you ever wanna reproduce the solar spectrum, you can't just match the color temperature
That's why the 5000k 80CRI led spectrums sucks so much at growing plants

[sdfoster22]

Yes, not all color temps of the same produce the same photons. We need to pay attention to photons. I believe 90 cri produces photons that help the plant sleep and grow during dark hours hence the farther red shift in the output. I could be wrong, but from what I've read it seems to be the case. These strips could also have different photons than 90 cri cobs and so forth. Again it was just an idea. I want to replicate the changing of days and seasons. Maybe not exactly daylight, but dial it in to something that works close, if not better than that.

[LivingLight]

For such purposes, the vesta could be decent.
Dimming both 2700k 90CRI and 5000k 90CRI independantly, you got an easy solution to reproduce some of the solar changes over days and seasons.

Then, if you wanna be closer of natural spectrum shifts, a far red supplementation would be necessary

[tazztone]

But what is r9? does it correspond to a nm frequency or is it something else?

again, just a measure of how accurate a certain color (in R9's case: red) appears to the human eye compared to daylight.
the frequency (nm) of the spectrum on the other hand can be seen in the spectral distribution curves. the only thing these LEDs really lack is UV.

[unkle_psycho]

So I'm about to pull the trigger on some vestas, and build a lamp for 2 x 4 to start with. Now I'm wondering between two setups.

A.
4 x 75w thomas research products drivers
6x 2ft Vestas

Here Each 75w driver sends 25w to 3 sides of a Vesta. Total power would be 300w, and maximum power per color tone would be 150w.
It offers great bang for the buck, and a total output of 37.5w per square foot, but as a downside if I wanted to flower with 2700k max output would only be 18.75w / ft2.
I'm sure I could live with this, but I think I would not feel confident bragging about the versatility of my creation.

B.
6x 75w thomas research products drivers
9x 2ft Vestas

Here total output numbers are overkill, with a total output of 450w and 56.25w per f2. Max per channel is still only 225w, or 28w per f2.

Here I could actually use the versitality of the Vestas, and have usable power at a range of color temperatures. Downside would be that I would almost always be dimming all channels quite a lot, so it would be inefficient.
I think 5 drivers would be enough for this. Two on the 5000k side and 3 on the 2700k side, but then I would have to divide 2 drivers between 9 channels.

[tazztone]

well why don't u go A and veg & flower with 3850K?

[unkle_psycho]

That would be the ultimate bang for your buck solution.

I'm new to growing with leds, I've only really used HPS and sulfur plasma. Now I'm also new to growing a couple of big plants inside, so I figured I can benefit long term making this my 'research light'. I'll use it to test optimal colour temperatures for each sativa dominant clone i concider keeping, and as I practice growing 180cm plants inside I will probably save my ass multiple times by cutting stretch with 5000k.

But I'm not sure 3700k will be the perfect flowering freq. I'm sure it will work, but I traumatized myself flowering a few crops with a 4500k plasma, so... I'm overthinking as i recover.

A few examples from my current pheno hunt run, node distance between the HPS and plasma:
G13xHawaian #1 5cm/2cm #2 9cm/5cm
Ice 10cm/4cm
Jack #2 9cm/4cm

Since I want to use side lighting and grow tent height plants, I think I will benefit a lot being able to veg with a spectrum optimized for the plant, and I never flowered with led's so for now all I know is I never want to flower under 4500k again.

[tazztone]

lots of people recommend 3500K for combined veg&flowering, so 3850K with 90CRI (red shift) spectrum seems similar enough. i am no pro tho

[unkle_psycho]

On the upside if I make it with 9 strips and 6 drivers it would have 450w running at 50w per strip, so it could work as a 4x4 light with slightly lousy side coverage, or as a single spectrum light for 2x4...

For side lighting I think these are too intesnse, I would likely go for 8 1foot eb gen2 strips per TRP driver... they only have 3500k and 5000k at digikey.fi