CMH vs LED vs HPS

[goingrey]

The LED and bud quality thread is a different one.

This one is about the benefits and disadvantages of these three commonly used lighting technologies. Which is a worthwhile discussion IMO. If you disagree, that's fine, but the thread title seems clear enough.

That said, claiming LED bud is better than ever is admitting that there is a difference. Understanding the differences would let the grower make a more informed decision on which light to use in which situation.

The horse ain't dead yet. You guys touting the same opinion over and over again are beating a live horse, sick fucks.

 

[Jaysways]

This is a strain called acid dawg, it’s grown under LED 300watt osram. A top nugget vs a low nugget. It’s not lacking in any department, me and my friends have been smoking since we was 15 , I have used every light possible and I’m growing the best to date BECAUSE MOST PROBABLY I’m a hell of a better grower and the genetics today are way better, give me 1000 watt hps and I will grow some good shit but give me a 1000 watt led fixture and I will blow that out of the water. You guys think this is a great thread, nobody’s comparing data, apart from crooked8 and all the hps growers are just going on there opinion and the great bud they “use to smoke”

“Opinions are the cheapest commodities on earth”.

Show us some fantastic hps grown buds by you yourself @snakedope
Because I’m telling you now “mate” your shit is not in the label as this new genetic here grown under hps or led

 

[Jaysways]

What I’m trying to say is I think LEDs are better and genetics are better today and hps pretty much suck compared to what’s are the market today happy Friday

 

[Crooked8]

The LED and bud quality thread is a different one.

This one is about the benefits and disadvantages of these three commonly used lighting technologies. Which is a worthwhile discussion IMO. If you disagree, that's fine, but the thread title seems clear enough.

That said, claiming LED bud is better than ever is admitting that there is a difference. Understanding the differences would let the grower make a more informed decision on which light to use in which situation.

The horse ain't dead yet. You guys touting the same opinion over and over again are beating a live horse, sick fucks.

So “benefits and disadvantages” does not include quality of final product from each category? I also find the discussion worthwhile. This is why I am showing what can be done with Leds. I thought this thread was about explaining the differences clearly so one can make the decision in an informed fashion. Am i missing something?

Pros vs cons of cost, efficiency, spectrum, convenience, yield, and the biggie of all in my opinion in regards to light category is quality.

 

[Broggemann]

Guys think this is a great thread, nobody’s comparing data, apart from crooked8 and all the hps growers are just going on there opinion and the great bud they “use to smoke”

“Opinions are the cheapest commodities on earth”.

...and at the same time, this guys does exactly that, sharing nothing but his pure opinion without anything to back it up.


Keep it going guys, this comedy gold.

 

[Crooked8]

...and at the same time, this guys does exactly that, sharing nothing but his pure opinion without anything to back it up.


Keep it going guys, this comedy gold.

He literally just posted his led product.

 

[exoticrobotic]

The LED and bud quality thread is a different one.

This one is about the benefits and disadvantages of these three commonly used lighting technologies.

How do we tell the benefits and disadvantages without testing the end product?

I bought an led array to keep the temps down while flowering in the middle of summer.

Turns out the plants i grow need that high temperature while under leds so i have to buy some heaters....They also need extra Calcium, Magnesium. They also need greater time in veg...

Ha! What an expensive joke.

But hey, cmon buy all the extras you never used to need.... Led is the way forward afterall, isnt it?

 

[Cerathule]

Have u ever thought why does big commerical ops put HIDs more then 3m above the plants ? What does a 3m high 1k hid ppfd look like ? Probably very lame, but still you get stellar plants and final product... How is that so ?
Even certhule would agree that light don't disappear, it's absorbed and travels until it do
So the distance is more a factor of how much light will hit your plants totally, but the plants still knows there are many high intensity sources above them, like you, you look outside and everything is nice and light is all around, your eyes are fine, but when u look up you know that the light source which create this "weak" eye level light is much more stronger then what u see here, same happens with plants, they see weak ppfd maps with HIDs but they know these weak numbers are coming from a very powerful source and react to it even though the entirety of that source don't hit em from 1 inch away.

Edit - LEDs suggest another reality, a reality of the same intensity source no matter height or other sources, this is very different from nature.

I would like to see a definitive experiment done where someone builds an led light that mimicks exactly an hps, and just change one variable at a time.

As far as I can tell, the only differences between hps and led are, spectrum, heat output, and diffusion.

By diffusion, I mean how with hps, the photons emitted by the bulb bounce around the reflector and get scattered and leave the fixture at many different angles. As opposed to leds which are a bit more focused. I personally think that diffusion is what gives better "canopy penetration."

I use quotes because I don't think it is about having a light source so powerful it actually penetrates the leaves/canopy. It is more about the photons being able to go around the leaves/canopy instead. And that is much easier when you have your light coming out of your fixture at all sorts of different angles like with hps.

Diffusion would be the hardest variable to measure/quantify, But probably can be done

I've seen a study where they used a special amber-diode to mimick the HPS spectrum (later I'll look if I can find it) but the various leaf-measurements where mostly different. The HPS was superior. That said, I feel like most studies aren't able to replicate a true "even" scenario, even Bugbee has so many methodlogical errors in what he -or his students- does.

One of the greatest error is just using a quantummeter to measure top-canopy PPFD, then rigorously adjusting said number to equal levels. If you do that with different lightsources that have either (a) different spread out beam angles or (b) different reflector hoods then still the plant could be distributed a various amount of photons per second. Because a quantum/luxmeter only takes a flow-measurement, that is, it tells you how much light comes from the direction into the other, and that is based on heading of the sensor. Most of the time, when measuring a live situation, we are adjusting it towards the main source of light in and then most of the rays are actually direct light. But this neglects diffuse light, and especially the ratio of direct vs diffuse light, which can be greatly different for any given lampsystem.

Now a quantummeters measurement can never tell you how many photons per second is hitting a given leaf - as it doesn't register all the diffuse photons coming from the sides, or below for that matter. It just gives you the highest reading and a clue of its direction --> which is still important as usually plants may alter their leaves and point them into that direction (not always).

This systematic error gets exacerbated by the lighting industries famouts "ppfd plots" where they will only use spotmeasurements in a 90° angle. If they would change the angle the numbers would vary dramatically. There can be so much manipulation done, to make a bad light look good and vice versa. For example, we know that any reflection will result in a loss of total photon count, yet some manufacturers will compress the normal 120° beam angle into a 90° one. Am integration sphere test would show this loss (PFD) yet a 90° fixture shows WAY HIGHER numbers at the ppfd-plot. Now if you change the spread you alter a few variables which causes this, that is
(a) less diminishing with distance (better deep effect in situations where individual rays make it into the canopy in between the top leaves)
(b) the side photons touch later any wall/grow tent which results in less reflective loss and more direct vs diffuse light.
So on paper it looks better but in reality it is not. Or, at least, not always, because it really depends on the specific situation in which a fixture is used:
If you are having a closed grow-chamber with adequate or good reflecting walls then diffuse light or high beam angle is favourable - plants love diffuse light, and if lightrays come from more directions then this can lead to more canopy "penetration" as well....
If you have a huge hall with multiple fixtures in a cross-lighting scenario then most, if not all, photons will directly hit the canopy then there's no point in introducing an early reflective loss via fixture reflectors or blends.
Now in another case where a lamp just hangs over a plant in a windowsill grow it makes perfect sense to concentrate the photons right at the plant because a higher beamangle (or most diffuse light) will increasingly just hit the carpet or fly out of the window, and so, be lost.

 

[exoticrobotic]

And all this knocking of bro science....

Bro science got this plant to where it is. Not lab reports.

This caper has turned far too science based as it is.

From simple hps, cmh to led. from 2 part feed to 9 part feed.

All about the $$$ not the plant...

 

[exoticrobotic]

Blinded by science...

 

[Cerathule]

I've seen a study where they used a special amber-diode to mimick the HPS spectrum (later I'll look if I can find it)

Found it, attached - it's even done on cannabis.

 

[Cerathule]

All about the $$$ not the plant...

Blinded by science...

In a way your critic is true, but it's not really the fault of the scientific system - which is actually not here to give us an absolute "truthful" answer (as it can't do that in most cases) but just snapshots an experiment and has set standards in place to deal with known errors. But there still are many errors left, esp. when said studies come from younger peers and so on. And then what's in the study just can't be generalized to many live situations, and that is something that's constantly done by non-scientists. A professor in his given field takes these informations just in another way... so IMO it's better to spend some money to buy a book from a respectable source than learn by the internet (if the option is available).

Another major source is really the capitalistic driven sellers, they spread so much nonsense it's unbelievable and the internet gives them full liberty to do so. And that is tragic when we keep in mind how much environmental pollution is generated by growing cannabis, by overlighting, by overfertilizing and then the US/Canada etc throw so much of their products into the trashcan. They've clearly oversaturated the market to point where they need to take special tactics in order to still sell with profit, not to better the quality of the product.

My personal believe is that LED spectras can still be better in both output and the light's biophysical properties towards the plants. Most LED spectra lack farred - which uses less energy per photon as even the curreent best standard (660nm). And why? Because the industry didn't read Emerson et al, and didn't understand the errors in McCree's work. And mostly still fail to understand that the chlorophyll molecule dissolved in acetone, or diethyl ether, is something way different as live in a rigid, genetically fixed macrostructures such as the light-harvesting supercomplexes.
It's not all their fault because even yet today, with our best and newest techniques (like polarization-dependent two-dimensional electronic-vibrational spectroscopy) there still remains some questions open on the greenlight absorption. Yes, it's absorbed, not reflected (at least, not by chlorophyl), but the excitonic states are not to be pinpointed precisely to be localized to specific chlorophyls or chl-complexes. There are a number of rivaling explanations still out there, and so is the scientific standard that they need to be very sure, clear all doubts, in order to release a confident statement.

 

[exoticrobotic]

I also believe at some point leds will surpass the performance of HID lights but according to my expert cannabis mindlab they are not at the moment.

I reckon most commercial nurseries growing various other plants and cannabis are still using plasma, cmh or hps for good reason.

The have, how to say, scientifically..... Ooooomph

 

[exoticrobotic]

Most LED spectra lack farred

They certainly lack something... They are not relaxing to be under for me.

They seem to lack light penetration ( green ) and warmth ( far red )

 

[cfl...KING]

With all this arguing, how do y'all have any time to take care of your plants?

 

[Cerathule]

Thing is, I really could care less about hemp. It's mostly burned, anyway. But I absolutely hate our local supermarket vegetables and some fruits. 10 years ago living in the mountains and had my own garden, just like my grandparents used to have - you can really taste the difference. The supermarket stuff just lacks taste, it's coarse, dumbed-down, younameit, and perhaps even lacking in nutrients or secondary "health" molecules. Even when I venture out here to the fields and handharvest some veggies, immediately cook them the taste is also way better. Potatoes for example, back then they had a much different, thicker "skin" - and they could be stored under the right circumstances for more than half a year. Now these supermarket potatoes mold after 4 weeks. With the house back then having mold everywhere, as it was build in 1753.

Is it the artifical light? Or the nutes, the medium? Or the climatal environmental conditions? Maybe insects/pests? What would constitute a healthy training for a plants genome's response? Maybe it is none of these points or all of them in combination?

 

[zachrockbadenof]

. But I absolutely hate our local supermarket vegetables and some fruits. 10 years ago living in the mountains and had my own garden, just like my grandparents used to have - you can really taste the difference. The supermarket stuff just lacks taste, it's coarse, dumbed-down, younameit, and perhaps even lacking in nutrients or secondary "health" molecules.

well if u live on the east coast of the u.s. , your veggies come from calif... a grower can't pick the tomatoes (for instance) at their peak like i can do in the summer in my garden- they pick em maybe green, or when they r 1st turning.. afterall they gotta be boxed n transported.. hence the shitty taste.

same thing for pineapples.. they are picked early, n they will ripen further...but... they will not get sweeter..

but not to worry... with global warming even in the cold zones, you will be able to grow summer veggies all year long...

 

[greencalyx]

Someone here mentioned earlier that this happens with some commercial cannabis, too. It is harvested too early for economic reasons, just like tomatoes and pineapples, and just like tomatoes and pineapple, the quality suffers

 

[Mitsuharu]

Understanding the differences would let the grower make a more informed decision on which light to use in which situation.

The future is already the situation now, energy saving because it's expensive and the planets resources are sucked up by the human race... So there will be no other situations than using LEDs.

but not to worry... with global warming even in the cold zones, you will be able to grow summer veggies all year long...

...if you have enough water.

 

[exoticrobotic]

energy saving because it's expensive and the planets resources are sucked up by the human race.

I'm not sure leds are the answer to energy efficiency in the home.

The non grow ones used for house spot lights seem to blow every few weeks.

Must cost a fair bit in energy to produce them.