Crackpot Growing Theories 101

Any information contained in this thread is to be considered theoretical, experimental, and otherwise completely nuts. If you're looking for a how-to this is probably not the right place.

I'm starting this thread to discuss the possibilites of creating a poor-mans spectrometer from a webcam and a home-made spectragraph consisting of an old CD and cardboard tubing. This is probably going to be my first order of business.

I am also proposing growing with lasers, that's right, I said it, lasers. Just because I think I'm the first one to try something so ludacris. And with 6.5 billion people on the planet it's getting harder to find things to do someone else hasn't already done. Before you say I'll just burn and kill plants I'll say you might be right, but that's not going to stop it from being attempted. They would of course have to be diffused and the beam would have to be spread, but hey let's see what happens... ...pending I don't get too many irons in the proverbial fire at once.

it was pointed out to me that a blueray laser while not cheap, may be a common source for a blue laser as I'm planning on collecting most of them from used optical drives. Now.. in my research I found out two things, 1. a blueray laser has 5 leads and 3 different laser diodes in it, so it can put out ~400nm light ~650nm light and ~800nm light (don't quote me on the exact values I'm not looking at the specs right now) all in one neat little package... and 2. the laser in a blueray is the same laser emitter that was used in the now-defunct HD-dvd technology, and you can pick up an xbox360 hd-dvd from ebay for around the $30 mark.. *cough* generous donations are always accepted :D

DIY Digital Spectrometer

Required materials:

There are two links to DIY spectragraphs, the difference between that and a spectrometer or spectrophotometer is former will show you the spectra and the later will measure it. We'll need the former to make the later so anyone on board should either already own a simple spectragraph or get busy making one.

C'mon it's fun and you can look through it and see clearly what colors of light your lighting is putting off and to what intensity

I didn't really follow the instructions so closeley, Mine is made from a giant cardboard tube from an empty roll of mylar cut to 25" and an old bon jovi cd I didn't mind splitting in half. I used a plastic lid from a can of tobacco to make the cover with the slit in it. I'll post pics if I absolutely have to :D

Fitting it together

this is a much cooler spectragraph than the cardboard tube, more durable as well

uses a dvd case

Sounds like a cool project.

i'm onboard farred! this sounds very cool!

the lasers thing is cool too! why not, right?!

subscribed.

i feel myself more and more everyday being sucked into my den, learning, reading, trying and reseaching crackpot!

-shake

I think the laser thing is maybe possible, I was looking at this home made spy gadgets book with a plan in it to make a high powered nightvision illuminator from a laser. It looked like he just spread the beam with a little 10x optic peice, and it put off easily 10x the illumination as an LED illuminator spread over a nice area at a HUUUGE distance but it got me thinking... why not i have a few optic peices i collected when i saw an article on solar puffing ( no matches or lighters :) ) so I guess all there is to do is get one, or some, of those xbox hd-dvd drives and see if the the 405nm/650nm/780nm lights it can produce are 'close enough' building something to heatsink them and power them is not a big deal then finding a lens or combination of lenses that give the right amount of beam spread and probably shine it through something to difuse the light but perhaps not, results would say for sure.

this is the of light intensity of the hd-dvd lasers same laser diode as in blueray

Quote:

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Originally Posted by farredeyed

I think the laser thing is maybe possible, I was looking at this home made spy gadgets book with a plan in it to make a high powered nightvision illuminator from a laser. It looked like he just spread the beam with a little 10x optic peice, and it put off easily 10x the illumination as an LED illuminator spread over a nice area at a HUUUGE distance but it got me thinking... why not i have a few optic peices i collected when i saw an article on solar puffing ( no matches or lighters :) ) so I guess all there is to do is get one, or some, of those xbox hd-dvd drives and see if the the 405nm/650nm/780nm lights it can produce are 'close enough' building something to heatsink them and power them is not a big deal then finding a lens or combination of lenses that give the right amount of beam spread and probably shine it through something to difuse the light but perhaps not, results would say for sure.

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definitely sounds plausible. makes perfect sense. if a laser is merely amplified light, why not use it in laser for travel (much more efficient i assume) and then diffuse into the necessary pattern?

-shake

this is a must read, granted they grew vegetables but it's all produce right?

http://www.hortiled.ff.vu.lt/apzvalg...wer%20leds.pdf

falls in to some extent with the martian method, being that they used far red and experimented with night cycles.. I'm most interested in how contrasted the concentrations of different phytohormones were in the same plants just by altering the far red usage.

And looking into that laser unit more, since its readily available in hd-dvd players people are selling off cheap now that they're obsolete, it's completely realistic to think you could get enough of them for some serious output, its also convenient that the optics in the laser head of the player contain most of the optics that would be necessary. I think the IR wavelengths it produces should be sufficient to pull off the martian nights, but I'm wondering if the 405nm violet-blue it makes would be enough alone to pull off a worthwhile effort isn't that too far off target? The red 650nm should be great, but the output of these laser diodes is only about 10mw each. Although if i could get my hands on some hd-dvd burners cheap the laser diodes in those are cable of 100-200mw output more than enough to start a fire. I imagine, once diffused, polarity shifted, and spread out it would still be pretty intense beams of light. I guess even if it didn't succeed I could say i didn't succeed first :D.


edit: -quick attempt at learning to spell

"I guess even if it didn't succeed I could say i didn't succeed first :D"

Hold that thought. :)

No wanna throw cold water on yer fire here.
But, that can happen when hot air gets out over thin ice.:D

You've got 2 worries here.

1st. 200 milliwatt won't grow squat.
Don't matter how you spread it, diffuse it, or diffract it, you will need a LOT of diodes. Hundreds, in fact. (200mw X 200 = 40W. minimum.)
Then there's bandwidth.
LEDs are a much wider bandwidth than laser diodes.

We can get good results from cheap red leds at a 620 nm. wavelength because the light frequency is a curve in ordinary leds.
Output is centered at 620 but still has useful energy from 580 to 660 on the slopes of the curve.

Laser diodes have very little "spread" !
What you see, is what you get.:(
420 nm laser diode will have almost zero output at 460nm
It seems powerful and intense because it is coherent, almost a single frequency, and thus can be focused to an extremely fine point.

What you need to succeed is the proper frequencies of light with enough photons per sqft to build a big bush.
Bottom line, I doubt that it's a viable plan.

That said, please, do it anyway.
"Not succeeding first" is valuable information for the rest of us.:cool:

Half the fun is:weedpoke::weedpoke: anyway, ya?

Aloha
Weezard

if they have 1/10th the bandwidth, at one 1/10th power isnt that the same amount of power for that one focused wavelength as far as measuring power per each wavelength, anyway, even if it doesnt end up working as a standalone unit. I'll be interested to see if the phytochrome responds to the 780nm wave, and I'm pretty sure any extra 660nm red will be happily soaked up. I'd like to see an actual datasheet from these manufacturers it seems like theres alot of speculation about the power of these diodes. I read one place that the ps3 and xbox hd-dvd had the same laser diode in their laser head units, then at what i would consider to be a more reputable source of info on led's and lasers the ps3 laser diode was quoted at being 10-20mw MAX where the xbox diode was mentioned to be capable of >100mw.. I'm starting to think about thinking more economicly and use this old dvd burner laser here in front of me which produces 660nm and 780nm that can be seperately controlled and should be able to do >= 200mw output each and look at cfl's for a primary light source.

another little DIY project i found that looks worthwhile
S.P.R.E.E. (Solar Photovoltaic Renewable Electron Encapsulator), a Compact, Durable, and Portable Solar Energy Generator
...but you might want to swap the battery for a deep-cell, get a 1000w inverter, add cooling and 5 extra solar panels

Anyway, I've been discussing making the poor-mans spectrometer amongst people, and I've heard some new ideas like using photo-resistors wrapped in color gel filters(that might be fun to and you could make it all analog easily after eye-balling the calibration from a known light graph and use a cheap led matrix display, I thought of using a honeycomb of photoresistors inside a spectrograph.

But as far as a 'project' I think it might be better to stay on track with the webcam idea as they're readily available and already assembled so the learning curve will be less like a cliff and more like plug and play. I've been made aware there may be some limitations of doing it this way.. 1) some webcams apparantly auto-color ballance (not this cheap one I've got) 2) the webcam's sensor detects RGB intensity levels, as far as I know, not UV V Vb bV IR etc... anything outside the visable range however most digital cameras do pick up IR maybe some are filtered but not all, but if you want to test yours turn it on and grab the remote to the television and point it at the camera's lens and push some buttons, if you see light in the video your camera is detecting IR, not that that matters for the purpose of identifying how much red or blue you're getting from your particular bulb at whatever its age and hours of use may be. blah blah words words... anyway I'm collecting the nescicary resources to start working on the software. My insomnia has been bad lately so it's likely there may be a few days of innactivity soon.

Quote:

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What you need to succeed is the proper frequencies of light with enough photons per sqft to build a big bush.
Bottom line, I doubt that it's a viable plan.

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about that, is there a collection somewhere of the sets of formula's nescicary to convert all the different ways people reference lighting equiptment into something as beautifully simple as photons per square foot?

I'm kind of glad you doubt the viabilty of growing with light originated from lasers I like a little controversy. I guess I should rephrase my saying "at least I'll be the first to fail at it" I like the way Edison put it... "I have not failed. I have just found ten thousand ways that won't work".

Quote:

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i feel myself more and more everyday being sucked into my den, learning, reading, trying and reseaching crackpot!

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speaking of which, I was wondering if you were thinking about trying those red incandesants alongside your cfl's Shake?

Quote:

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Originally Posted by farredeyed

about that, is there a collection somewhere of the sets of formula's nescicary to convert all the different ways people reference lighting equiptment into something as beautifully simple as photons per square foot?

I'd say that KNNA is your "go to guy" fo' dat.

I'm kind of glad you doubt the viabilty of growing with light originated from lasers I like a little controversy. I guess I should rephrase my saying "at least I'll be the first to fail at it" I like the way Edison put it... "I have not failed. I have just found ten thousand ways that won't work".

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Zachary!:D

Though I have no worry with the origination, just the narrow spectrum and the max. power emitted.
Keep on :weedpoke: and you may find that the 10,001st way has more promise;)
When it's the journey you're after, the horizon makes a dandy goal.
Weeze

I quoted this from Sam's laser FAQ Sam's Laser FAQ - Laser Safety

Standard Sun:


Maximum intensity of sunlight at ground level (directly overhead, no smog, etc.) = 1 kW/m2 or 1 mW/mm2.

Assuming pupil diameter is 2 mm (i.e., radius of 1 mm), the area is approximately 3 mm2. So, the power of the sunlight through the pupil = 3 mW.

Focal length of eye's lens = approximately 22 mm. Angular size of Sun from Earth = 0.5 degree = 9 mR. Thus, diameter of image formed = 22 mm x 9 mR = 0.2 mm and the area of image = 0.03 mm2.

The intensity of the Sun on the retina (Power/Area) = 3 mW/0.03 mm2 = 100 mW/mm2.
Typical 1 mW HeNe laser (or laser pointer):


Power (P) = 1 mW, wavelength (l) = 633 nm, radius of beam (w) = 1 mm, focal length of eye (f) = 22 mm. So, the diameter of spot = (2 x f x l)/(w x pi) = 9 x 10-3 mm and the area of spot = 6 x 10-5 mm2.

The power density of the HeNe laser on the retina is 1 mW/(6 x 10-5 mm2) = 16,667 mW/mm2 = 16.667 watts/mm2.
So the 1 mW laser has the potential to produce an intensity on the retina 167 times that of direct sunlight!

granted, a plant is many times the size of a retina, and I'm pretty sure focal length wouldn't play into it, but i think even after being dispersed over an area say .3M squared a 100mw 780nm laser could produce enough far red to speed up your nights especially if you start adding more lasers since it contains no red, and not any really high infra-red that just makes heat, and looking at a solar chart, of watts energy at ground level per nm wave it looks like the sun is delivering about 1 watt per nm at the far red levels

I realize lasers are really inneficient compared to LED as far as lumens per watt, I just don't see any high output ~730nm(ballpark) LED's laying around here to play with.

ok here's a cpl pics to show the webcam spectragraph app's progress.. try to remember Rome wasn't built in a day ;)

sorry 1 pic, i'm having trouble uploading X(