Have any of you DIY COB Growers finished a crop under 1000W DE HPS? - POLL

[cdgmoney250]

"Infrared light is certainly not any hotter than visible light.

On the contrary, the same number of infrared photons carry a lot less heat than visible light photons.

What is the hottest object with which we are all familiar? Why, the Sun of course. And guess what... most of the Sun's heat comes in the form of visible light. The Earth re-radiates the same heat into space (if it didn't, we'd all boil in short order) in the form of infrared light, but to do so, it emits approx. ten times as many (infrared) photons than the number of (visible light) photons it receives.

So why, then, is it your perception that infrared is "hotter" than visible light? Because most hot things that you are familiar with in everyday experience are a lot less hot than the Sun, and the peak of their emission spectrum is in the infrared, not the visible. Meanwhile, the light sources you typically encounter are feeble, emitting a lot less power than a typical heat source.

But if I were to make you stand in front of a source of 1000 watts of white light, I assure you, it would feel just as hot as standing in front of a 1000 watt electric heater. No difference... a thousand watts is a thousand watts. But the heater would be emitting a great many more (lower energy, infrared) photons than the light source to produce the same 1000 watts. Conversely, if I made the heater emit the same number of photons, it would only emit around 100 watts, so it would feel a lot less hot than the light source."


Written Jan 21 By Viktor Toth physicist/ IT specialist

https://www.quora.com/Why-would-infrared-light-be-hotter-than-visible-light-which-has-more-energy

 

[cdgmoney250]

They don't understand this , they just don't understand common sense, to them everything makes the same amount of heat all that matters is how much watts go to it, maybe if we lived in outer space in a vacuum that would be true, but here in the real world it's far from it.

Not just to us "LED Fans", but to the known world of physics and thermodynamics.

If you want to re-write the books, be my guest...

 

[PurpleBuz]

Perhaps, but the "peak" in the Mcree curve extends from around 600-680 so I'm okay with the highest relative brightness being to the left of 660... although I too would like to see the values stay strong til 680 and drop like a rock. The real question is, what difference does it actually make?

I get what your saying about "680" but gee whiz the cree photo reds have a spread width of 650 - 670, and if you move too close to the 680 line some of the photons will be wasted on the other side of the shoulder. Better to be within the shoulder than slightly over the shoulder.

whether its worth it or not is a different question. grows are good without the extra 660, but the cost to implement is small, only takes a couple of watts to supplement a cob.

 

[CannaBruh]

How quickly heat is transferred depends on temp differences and surface area, heat flows from hot to cold, and a larger difference in temperature makes faster heat transfer.

Will an HID lamp, cause a rise in temperature in our environment at a faster rate than a COB led? *(assume 100W true power for both)

 

[PurpleBuz]

How quickly heat is transferred depends on temp differences and surface area, heat flows from hot to cold, and a larger difference in temperature makes faster heat transfer.

Will an HID lamp, cause a rise in temperature in our environment at a faster rate than a COB led?

yes, temperature is higher because of the amount of photons above 730 nm

 

[CannaBruh]

Does this translate to a rise in ambient temps at a faster rate for HID than COB given same power in?

 

[platt]

probably yes ^
looks like plants build cell structures around water. In case of cold ambient temps wich lamp is gonna expose more water & dry matter to the environment?

http://www.tankonyvtar.hu/en/tartalom/tamop425/0010_1A_Book_angol_01_novenyelettan/ch02.html <---nice coffe reading

The extensive hydrogen bonding between water molecules results in water having both a high specific heat capacity and a high latent heat of vaporization. Because of its highly ordered structure, liquid water also has a high thermal conductivity. This means that it rapidly conducts heat away from the point of application. The combination of high specific heat and thermal conductivity enables water to absorb and redistribute large amounts of heat energy without correspondingly large increases in temperature. The heat of biochemical reactions may be quickly dissipated throughout the cell. Compared with other liquids, water requires a relatively large heat input to raise its temperature. This is important for plants, because it helps buffer temperature fluctuations. The latent heat of vaporization decreases as temperature increases, reaching a minimum at the boiling point (100°C). For water at 25°C, the heat of vaporization is 44kJ mol-1 – the highest value known for any liquid.

The excellent solvent properties of water are due to the highly polar character of the water molecule. The polarity of molecules can be measured by a quantity known as the dielectric constant. Water has one of the highest dielectric constant, which is as high as 78.4. The dielectric constant of benzene and hexane is 2.3 and 1.9, respectively. Water is thus an excellent solvent for charged ions or molecules, which dissolve very poorly in non-polar organic liquids.


@Rahz watch the water slope

stolen from here http://cse21-iiith.virtual-labs.ac.in/exp3/index.php?section=Theory

 

[THE KONASSURE]

actually any light will hit the air or what ever it hits and make heat too

hps is very cheap and very effective but the orange and such that it emits is not used by the plant very well, that`s not too bad because it does emit a lot of light that the plants can use

Also with hps vs good cob set ups, the hps can sometimes make for better roots, as it provides more heat, and can mean your plants drink more, this can be a down side when you have to work more to water them but it can mean better root growth, and you may not be able to afford to run 700w to 1200w of cob to get the same heat as a 600w hps

but most people seem to want less heat

hps`s work and can do a good job, but cob`s can do a better job in some cases and are not very expensive to make, if your after a 100w to 600w lamp these days you can make a cob unit pretty cheap using 1 to 4 chips, hell you can get some 2000w+ cobs if you wanna go mental

hps`s can be a lot of hassle when the ballast or bulb blows there`s a lot of glass to deal with, its the main down side to induction lamps too, who want`s to deal with all that glass ? it`ll just get broken or need cleaning some day

 

[Sativied]

Hahaha
You haven't proven anything.
Either test a COB personally and post the results to back your "claims" or post a study that actually compares white light LED to HID. Not the Blurple lights you keep referring to and citing.

I'm sure once you renounced the use and authority of reason it may seem like that.

Tell me though, why does it makes a difference between blurple and white if it's all light=heat anyway...

This would go smoother if you guys would stop changing the argument to a hypothetical situation in a vacuum, and then back to reality when it suits you.

There's likely no study that compares leaf temps under an equal amount of input watts between hps and white led. Pros and scientists don't go along with your fantasy red herring argument.

How you guys can still take yourself seriously is baffling. As you have proven, all you got is par w efficiency. The rest is wishfulthinking derived from that to justify the cost. And now when temps are compared, you want to pretend it's irrelevant and an equal amount of watt is used. Pathetic really.

Par watt + convection and conduction = led
Par watt + convection and conduction and Ir = hps

You clowns are comparing the IR of hps, part of what you consider wasted, reducing efficiency, with the useful part in LED...


Note the wattage of the CFL and the temp of the leaves... and stop lying.

White Cree Cobs:

Clearly too cold... CLEARLY.

It (white resulting in more heat in plants than leds designed for grow light) was your best argument so far... perhaps you should explain to your cult members that apparently, in reality, what matters is the effect it has on plants. Essentially white cobs are better at warming up plants than blurple (which I never suggested you use, many mixed blue and purple lights actually contain some white leds too).

You are making the bold claim that goes against an endless amount of pro research and real world experience, buy a flir, you prove yourself right before so desperately trying to prove me wrong. It's your purple dragon, not mine, I merely report facts, you guys make shit up.

Look forward to see how you led fans try to squirm your way out of this one. Apparently pictures are more effective than text...

It's like you see proof of the Big Bang and then claim God is responsible for that too..

"When a photon of light hits a plant leaf, it can either be reflected or absorbed. Reflected photons will not affect the leaf temperature at all, but physics dictates that all photons absorbed by the leaf will increase the leaf temperature; how much depends on the energy (wavelength) of the photon and whether or not some of that energy was used to trigger other chemical reactions, such as photosynthesis. Photons fully utilized by the plant in chemical reactions will heat the leaf less than photons which are absorbed but not utilized. Therefore, measuring leaf surface temperature indirectly measures the efficiency of the light spectrum for growing plants-- less-efficient spectrums will tend to heat the leaf more, while more-efficient spectrums will heat the leaf less as more of the light energy is being converted to chemical energy.

High Pressure Sodium (HPS) in particular converts a significant portion of the energy consumed by the light directly to non-visible infrared light in the 810-830nm range, peaking about 819nm. This infrared light is perceptible to you (and plants) by the warmth it creates when exposed to the light. Additionally, much of the visible light HPS bulbs produce is yellow and not highly-utilized by plants. This radiation not used for photosynthesis or other chemical reactions only serves to heat up the leaves,
"

You're welcome.

 

[Sativied]

@Greengenes707 melted/burned his tie from a cob for fuck sakes...

see my comment on intuition vs reality in the light direction thread... And yes, cobs create hotspots, in a canopy usually only at the top, so sad you need 'that' to warm up plants lol.. The par watt is absorbed and used more than Ir and does not penetrate the plants as well, pots with roots even...

 

[Yodaweed]

Not just to us "LED Fans", but to the known world of physics and thermodynamics.

If you want to re-write the books, be my guest...

The spectrum of the light directly correlates to the heat it makes. That is how they discovered IR radiation, read this article.

http://www.brynmawr.edu/chemistry/Chem/mnerzsto/Marshall-Infrared.html

It explains how IR was discovered and how it has a higher temp than other spectrums of light, the more IR in the light source the more heat it produces so not all lights produce the same amount of heat.

 

[bicit]

Sine this thread has attracted a lot of knowledgeable people from all sides of the isle - Has anyone heard of a manufacturer that makes a 600W Square Wave ballast?

I've been trying to find an answer to this question to no avail..... A 600w fixture would be much more effective for me....

Been trying to get info about growlites new DE 315w CMH bulb, but they're being pretty mum about it....

I'm sure for some HID is convenient, however it's a pain in the ass to scale unless you conform your grow space around them....If you want something just a little bit different it's a PITA....

 

[Yodaweed]

I've been trying to find an answer to this question to no avail..... A 600w fixture would be much more effective for me....

Been trying to get info about growlites new DE 315w CMH bulb, but they're being pretty mum about it....

I'm sure for some HID is convenient, however it's a pain in the ass to scale unless you conform your grow space around them....If you want something just a little bit different it's a PITA....

They make like a million different HID reflectors....all different shapes and sizes i'm sure you can find something to fit your growspace.

 

[bicit]

They make like a million different HID reflectors....all different shapes and sizes i'm sure you can find something to fit your growspace.

Right, and usually you have to deal with design compromises and/or lower quality components.... Not to mention the smaller stuff is produced in small lots and tend to come at a considerable monetary expenditure. It's what drove me to LED in the first place. Really as far as modularity and flexibility it's hard to beat DIY cobs on CPU coolers. Damn near like an adult version of lego's. It allows me to maintain a given PPFD on any scale, from PC tower to warehouse. Without a sacrifice in component quality or electrical efficiency. Monochrome LED's can do this too, but it's a bit more complicated to actually achieve compared to cob lamps.

Hell even for the commercial users, the modular nature of cobs comes in handy. On a large scale the implications are even more interesting as there are certain technologies that don't really scale down to the hobbyist level. It opens up the door to other configurations that could prove to be more viable. There are other ways to supplement IR. Really wouldn't count against the electrical efficiency of the LED panel if it's a necessary component for optimizing the fixture. Time will tell.

 

[Yodaweed]

Right, and usually you have to deal with design compromises and/or lower quality components.... Not to mention the smaller stuff is produced in small lots and tend to come at a considerable monetary expenditure. It's what drove me to LED in the first place. Really as far as modularity and flexibility it's hard to beat DIY cobs on CPU coolers. Damn near like an adult version of lego's. It allows me to maintain a given PPFD on any scale, from PC tower to warehouse. Without a sacrifice in component quality or electrical efficiency. Monochrome LED's can do this too, but it's a bit more complicated to actually achieve compared to cob lamps.

Hell even for the commercial users, the modular nature of cobs comes in handy. On a large scale the implications are even more interesting as there are certain technologies that don't really scale down to the hobbyist level. It opens up the door to other configurations that could prove to be more viable. There are other ways to supplement IR. Really wouldn't count against the electrical efficiency of the LED panel if it's a necessary component for optimizing the fixture. Time will tell.

Yeah also LEDs are missing UV light, that's really important and the only reason I run a MH between my two HPS lights. LEDs are the future but got some ways to go in my opinion.

 

[bicit]

Yeah also LEDs are missing UV light, that's really important and the only reason I run a MH between my two HPS lights. LEDs are the future but got some ways to go in my opinion.

Most HID fixtures are missing UV as well, once you've got open rated bulbs or the glass from an air cooled reflector the amount is typically minimal at best.... For small fixtures forget it.

By comparison if you really wanted to, you could drive LED's low and slow while running fluoro UV bulbs and actually hit a targeted amount of UV . Rather than guessing what your MH bulbs are putting out by the time it actually hits the canopy.

IR could be worked in as well with more precise NM range, quantity, and delivery for optimizing photosynthesis rates.

 

[Yodaweed]

Most HID fixtures are missing UV as well, once you've got open rated bulbs or the glass from an air cooled reflector the amount is typically minimal at best.... For small fixtures forget it.

By comparison if you really wanted to, you could drive LED's low and slow while running fluoro UV bulbs and actually hit a targeted amount of UV . Rather than guessing what your MH bulbs are putting out by the time it actually hits the canopy.

IR could be worked in as well with more precise NM range, quantity, and delivery for optimizing photosynthesis rates.

http://eyehortilux.com/products/specific/600w-Hortilux-Blue

These got a lot of UV light, remove your glass...they also have more far red than COBs and that's not even my far red light source.


Don't bother with Fluoro's they don't have much intensity.

 

[bicit]

http://eyehortilux.com/products/specific/600w-Hortilux-Blue

These got a lot of UV light, remove your glass...
View attachment 3640343

Don't bother with Fluoro's they don't have much intensity.

Yeah, UV-A, which LED can do quite easily and cheaply. Notice how the graph cuts off right at 380nm... The UV-B range is 280-315nm. That's the range most are interested in tickling when talking about UV supplementation.

Then onto technical issues. Single ended bulb limits you to single ended fixtures. Removing the glass hampers cooling as well as odor control. Limited to spaces appropriate for a 600w HID. Limited ballast selection (IE no leading edge square wave/low freq). The price of the bulb is obscene for something that has to be replaced frequently. Essentially just reaffirming all my complaints about HID lighting...

Yeah if you want to conform your grow space to them, they work great.... If you have odd ball requirements, don't sell for profit, or have a spotty supply chain you're SOL....

 

[Yodaweed]

Yeah, UV-A, which LED can do quite easily and cheaply. Notice how the graph cuts off right at 380nm... The UV-B range is 280-315nm. That's the range most are interested in tickling when talking about UV supplementation.

Then onto technical issues. Single ended bulb limits you to single ended fixtures. Removing the glass hampers cooling as well as odor control. Limited to spaces appropriate for a 600w HID. Limited ballast selection (IE no leading edge square wave/low freq). The price of the bulb is obscene for something that has to be replaced frequently. Essentially just reaffirming all my complaints about HID lighting...

Yeah if you want to conform your grow space to them, they work great.... If you have odd ball requirements, don't sell for profit, or have a spotty supply chain you're SOL....

They make other bulbs and designs I was just giving you an example but it seems like your mind is already made up. All your complains are easily handled by common sense. Need a bigger light? Get a 1000watt. Want a different type of light? Go DE or CMH. Having problems with heat? Use a portable air conditioner. Can't afford the top end bulbs? Buy these http://hydrobuilder.com/delux-premium-metal-halide-super-veg-bulb-600w-4-200k.html
Every one of your problems has a solution.

 

[bicit]

They make other bulbs and designs I was just giving you an example but it seems like your mind is already made up, well good luck to you.

Me thinks thou dost project too much..... If you know where I can find a LFSW ballast for a 600w bulbs I would be eternally grateful.

If you know where I can get 400w and lower rated bulbs that share the same electrical efficiency of 1kw HPS bulbs do I'd also be grateful. The 315w cmh bulbs aren't quite up to snuff and most of the lower power stuff suffers greatly I've noticed...