/diy/ - Do It Yourself

>>2710385
The window and bottom front are removable with magnetic closures. Ceiling has 24V growing led strips with some automotive connector I found

>>2710386
In the bottom also the only part I ordered, cheap 24v timer relay from Amazon

The ceiling can be removed too and had some vent holes, will add mesh screen later when I remember where I left it

>>2710388
Here’s what it looks like when on. The tin foil and tape are temporary, I’ll put reflective paint later when I get it

>>2710390
The net pot with rockwool hangs through the middle. The roots will extend into the reservoir with water and nutrient, like a kratky pot. This keeps the water reservoir in the dark preventing algae growth, and the top ‘soil’ dry, preventing flies

>>2710392
This is the previous one I built. Much neater but it leaks too much pink light into the room. Started from a single seed a year ago and gives me a steady supply of peppers (4-5 small ones per week) now

>>2710394
I put some cat grass seeds to test it, then a basil plant and then woodland strawberries

>>2710390
>>2710392
>>2710394
Neat setup
I'd ditch the purple lights and just get some white LEDs
Unless you like the aesthetic

>>2710470
Those lights are specifically for growing plants, white won’t work as well

>>2710486
I can go on a lengthy 1000+ character rant as to why there is no such thing as plant specific light or you can take my word on this.
Purple LED lights for plant growth has zero to do with what's optimal and has everything to with the economic and technical realities of their introduction to the market.

>>2710502
>there is no such thing as plant specific light or you can take my word on this.
Chlorophyll and other pigments involved in photosynthesis have distinct absorption spectra.
Light which is at the correct wavelengths is much more effective at driving photosynthesis in plants.
I agree that a lot of "grow lights" out there are less engineered for their ideal spectra and more so a trade off about what is practical to manufacture. Modern LED growlights seem to be the exception to this trend.
Pic related. https://www.life.illinois.edu/govindjee/paper/gov.html

>>2710385
You could have just moved south a little ways, big guy

>>2710559
This graph was peddled by early LED manufacturers to justify their shitty spectrum
This is the actual absorption graph and it includes all colors of the visible spectrum
https://www.sciencedirect.com/science/article/abs/pii/0002157171900227

Ask anyone who is really dealing with plant physiology and they will tell you that you can basically treat all colors of photons as equal for the purpose of photosynthesis. This is also represented in the tools used to measure photosyntheticlly active radiation. Most use a completely flat response curve.

>>2710611
That... Looks like chinese sunlike LED. In visible spectrum at least.
With 380 nm near-UV it would be almost perfect.
>>2710486
White isn't most efficient sure, but ppl who grow weed have noticed that white light gives better weed, hence all "yes definitely tomatoes mom" lights are white with just a few of red/deep blue LEDs.

>>2710611
You've got me curious, and now I'm reading the paper you linked:
This pic related is from page 199 in that McCree paper : https://annas-archive.org/scidb/10.1016/0002-1571(71)90022-7

It doesn't look that flat to me, but I am retarded and I'm too ignorant to understand some of the equations in the paper.

I'm also trying to figure out what the differences are between the results from McCree and the others in the literature such as the one that I pulled the >>2710559 chart from (https://sci-hub.ru/10.1007/978-94-011-4832-0))

>>2710611
I guess what is baking my noodle is: given that the absorption spectra of the plant pigments is very nonlinear, I would be surprised to find that their photosynthetic yield would be flat across the spectrum in terms of light delivered.... Wouldn't that mean that they were utilizing the less strongly absorbed light at a much more efficient rate?

I have a room temperature IQ and I still wear diapers.

>>2710571
Thanks, smart idea but I don’t speak Moroccan

>>2710470
I’ll look into it more, will build some bigger ones in the future when I have more space, if white light works that would be better.

>>2710628
No weed here, it smells and box is too small for weed anyway

>>2710670
It's not exactly flat but for the purposes of determining how much photosynthetic active radiation is getting to a plant, it's treated as flat.
Green photons are the least efficient at driving photosynthesis but that goes out the window at high light/radiation levels when chlorophyll is essentially "saturated" (paraphrasing) with light and quantum efficiency of red photons drop. Green can go deep into leaves and penetrate through leaves and ends up being used more efficiently than red in that situation.

>>2710720
that makes sense. As I read into it all more last night, I came to realize that the extremely nonlinear absorption curves shown for chlorophyll A and B and the other major pigments were findings from the pure pigments in solution under low irradiation levels.
It's the same way with the spiky photosynthetic yield charts that you see from LED manufacturers--- they're from single leaf exposure under low irradiation levels. Whole plant yields under realistic culture conditions is what matters more, and while the modern LEDs seem to be working OK in that department, the whole "blurple" lights thing and immense focus on spectrum is probably overhyped.

I must admit-- when you first posted that spectrum didn't really matter, I was highly skeptical. Everyone has seen the spiky absorption charts, and it kind of felt sensible that a tuned spectrum artificial light could have drastically increased performance by catering to the absorption spectrum of the dominant pigments. Then I started reading into it and the part about photosynthesis basically using individual photons and how increased energy levels of shorter wavelengths vs strong absorption of longer wavelengths leads to a situation in real plants that is different than the response of chloroplasts in a cuvette or whatever.

Cheers m8

>>2710924
>the whole "blurple" lights thing and immense focus on spectrum is probably overhyped.
Like I said before it has alot to do with the technical realities when LED grow lights first came to market.
LEDs where inefficient at the time and the only way to make a comparable efficiency light fixture was to use monochromatic red and blue LEDs. 445nm blue and 660nm red is pretty much the bare minimum for good growth and where also the most efficient diodes at the time.

This limitation was flipped into a marketing point when in reality the plants don't care that much. As long as blue, red and far red are in decent proportions, white light is perfectly fine and LEDs have evolved enough and the current market for LED diodes in general means that decent efficiency low-cost fixtures have to be mostly white light.

I'm not one to be really picky about lights, it's not like red/blue lights won't grow and if you actually like the look of the magenta lights then roll with them but it is nice to have a 3000k-4000k color temp white LED fixture for your own sanity and it very much bugs me that decade+ old talking points about "plant optimized LEDs" are still floating around.

>>2710941
where and were are two different words. You are intelligent, so why not learn what 4 year olds know.

>>2710390
Hailing from /hgm/ on /out/, I can promise you blurple is so last decade.
But, it'll work still - hope you didn't pay too much for them.

>>2710941
>>2710924
Thanks a lot for looking it up science anons. I will put some normal coloured led strips on the shopping list since they’re in my home office and the pink light isn’t great