MH vs HPS for yield?

[rives]

I thought that Wazzup's post in the DE thread was interesting - it explains why the DE lamp wasn't listed in the lineup of Philips' horticultural products. I wonder how effective they can be in limiting sales to their "approved" market? The only way that I've seen that work is by restricting sales to specific license or permit holders.

Hi guys. I have been extremely busy last few months and still am, but I will try to be here a bit more often. If you need support from Gavita, please visit the support system on the website.

About the lamp: Philips still makes them but as from March 2014 they are no lonmger sold in the Hydroponics market, just in the professional greenhouse market. Philips has distanced itself from the cannabis market for legal reasons.

So, indeed the DE lamp from Philips is no longer available on this market (other than old stock). Fortunately we are a Philips business partner and have seen this coming for a long while. Gavita introduced their Gavita Pro 1000W 400V DE lamp already more than a year ago and recently (just a month before the Philips ban) the Gavita Pro Plus 1000W 400V DE lamp. This lamp has the same output as the Philips lamp (2100 umol s-1) and no, it is not a philips OEM lamp , and it is uniquely built for Gavita in Europe.

I am not sure what the other suppliers are going to do, but I know there is an Ushio 1950 umol lamp, there are various Chinese 1850 umol lamps (highly NOT recommended), Osram and GE probably will follow the same policy as Philips does (the GE lamp isn't that good anyway).

 

[Pinball Wizard]

My main project now, is to see what is better at vegging. 4000k v.s. 7000k

 

[Drek]

I thought that Wazzup's post in the DE thread was interesting - it explains why the DE lamp wasn't listed in the lineup of Philips' horticultural products. I wonder how effective they can be in limiting sales to their "approved" market? The only way that I've seen that work is by restricting sales to specific license or permit holders.

I can understand Philip's limiting to the market it was intended for. They have a professional reputation to uphold, and really, none of their tech is intended towards the cannabis community(even though they are fully aware that they're popular in it). Commercial op's would have no problem I don't think, if they wanted to use it.

 

[Pangea]

I thought that was an interesting post as well. There are a few and many more on the way that are professional greenhouse cultivators who grow cannabis up here in Canada.

 

[Jhhnn]

I thought that Wazzup's post in the DE thread was interesting - it explains why the DE lamp wasn't listed in the lineup of Philips' horticultural products. I wonder how effective they can be in limiting sales to their "approved" market? The only way that I've seen that work is by restricting sales to specific license or permit holders.

Interesting question. What *will* happen is that it'll force up the price of those lamps in our side of the market- double middleman markups.

It may also be the reason that 315 agro lamps & hardware aren't easy to come by. I haven't quite figured out what else they're supposed to be used for, however....

 

[Drek]

I haven't quite figured out what else they're supposed to be used for, however....

Hey JH. One of the main purposes for the Philips new Greenpower lineup are to supplement natural lighting, as well as being standalone lamps for large or small commercial greenhouses. The greenhouse industry is a billion dollar industry. The main benefits of this lineup are efficiency and longevity and slightly higher output. Imo, spectral designs have more or less remain unchanged from older Agro offerings. It isn't what Cannabis culture seems to think (knee jerk reaction)...a magical new spectrum that sets a new standard. The new 'Greenpower' bulbs set a new standard in electrical usage and operating costs.

http://www.lighting.philips.com/pwc...lets/overview_growing_your_profits-hid-en.pdf

 

[RB56]

Hey JH. One of the main purposes for the Philips new Greenpower lineup are to supplement natural lighting, as well as being standalone lamps for large or small commercial greenhouses. The greenhouse industry is a billion dollar industry. The main benefits of this lineup are efficiency and longevity and slightly higher output. Imo, spectral designs have more or less remain unchanged from older Agro offerings. It isn't what Cannabis culture seems to think (knee jerk reaction)...a magical new spectrum that sets a new standard. The new 'Greenpower' bulbs set a new standard in electrical usage and operating costs.

http://www.lighting.philips.com/pwc...lets/overview_growing_your_profits-hid-en.pdf

If the information presented in the linked brochure is accurate and unless I'm missing something big, it contains the answer to the question in the title of this thread as well as directly addressing the question I raised earlier in this thread:

For one Watt of energy, almost twice as many red
photons can be produced compared with blue. This means that although they
still use the green and blue part for growth – or photosynthesis - they use the
red part of the light much more efficiently.

Really awkwardly phrased but from the paragraph above and supporting illustrations I conclude they are saying red photons are cheaper for us to produce and most efficiently used by plants for photosynthesis. Is it possible to conclude from this anything but that 1KW red biased HID is going to provide more energy for photosynthesis than 1KW MH? Possibly more efficiently? Or they could be lying

 

[Pangea]

In a greenhouse would a cannabis grower not still be at an advantage using HPS over a CMH to supplement?

 

[Drek]

If the information presented in the linked brochure is accurate and unless I'm missing something big, it contains the answer to the question in the title of this thread as well as directly addressing the question I raised earlier in this thread:

Really awkwardly phrased but from the paragraph above and supporting illustrations I conclude they are saying red photons are cheaper for us to produce and most efficiently used by plants for photosynthesis. Is it possible to conclude from this anything but that 1KW red biased HID is going to provide more energy for photosynthesis than 1KW MH? Possibly more efficiently? Or they could be lying

Plants need everything for optimal growth. That's why Horti lights have slowly progressed towards providing more of everything(apart from what people thought they knew before). RGB. That's no surprise tho, considering plant systems evolved around sunlight. A MH lamp at 3-4k would be more my choice. Apart from green energy being involved in Photosythesis; enhancing it and providing more penetration into the jungle, it makes viewing plant health so much easier. One can see deficiencies (more of an indoor problem) occurring quickly and be able to get on top of it. Metal halides lamps at the right color temperature provide all of it, while providing more visibility; at a lesser efficiency(CMH being the more efficient halide solution).

 

[RB56]

Plants need everything. That's why Horti lights have slowly progressed towards providing more of everything. RGB. That's no surprise tho, considering plant systems evolved around sunlight. A MH lamp at 3-4k would be more my choice. Apart from green energy being involved in Photosythesis and enhancing it, it makes viewing plant health so much easier. One can see deficiencies (more of an indoor problem) occurring quickly and be able to get on top of it.

Are you saying you don't believe the information in the PDF you linked? It almost literally says that only a fool would design a spectrum for photosynthesis using the visible spectrum. Please tell us what plants do with "everything"? We know they need light between 400-500 nm and 600-700 nm for photosynthesis. It looks like the red 600-700 range is more important/efficient since that where chlorophyll A lives. That leaves the vast majority of "everything" and a third of the visible spectrum. Please elaborate.

I pay for photons. I'd prefer not to waste any. If HPS is as much more efficient as your link suggests, I'd rather get color correcting lenses to wear while evaluating plant health than continue dumping energy on the floor needlessly for the 23 hours and 50 minutes I'm not looking at the plants each day.

 

[Drek]

Are you saying you don't believe the information in the PDF you linked? It almost literally says that only a fool would design a spectrum for photosynthesis using the visible spectrum. Please tell us what plants do with "everything"? We know they need light between 400-500 nm and 600-700 nm for photosynthesis. It looks like the red 600-700 range is more important/efficient since that where chlorophyll A lives. That leaves the vast majority of "everything" and a third of the visible spectrum. Please elaborate.

I pay for photons. I'd prefer not to waste any. If HPS is as much more efficient as your link suggests, I'd rather get color correcting lenses to wear while evaluating plant health than continue dumping energy on the floor needlessly for the 23 hours and 50 minutes I'm not looking at the plants each day.

Plants also need an adequate amount of green light. Green light should also provide for more penetration and even lighting.
- http://pcp.oxfordjournals.org/content/50/4/684.full
- http://hortsci.ashspublications.org/content/39/7/1617.full.pdf+html

Whether you want to pay for it or not, is up to you. RGB, essentially equals white light. I'm not certain, but I think the orange light given off by HPS, is a byproduct of the sodium plasma reaction(ie: all HPS lamps are predominantly orange). At lower relative energies, the Philips DE HPS lamps do provide most of everything...at lesser visibility, which important for me.

 

[the gnome]

well while it's interesting to note that photoyosynthesis is easier done with the far red means, it means what exactly?
it doesn't say that is what the plant prefers or needs more of red,
only a fool would would take it that way,
looking at the lite graph below that paragraph the need for red drops straight down in the usable spectrum for plants as soon as you get close to it.
plants do need some red but very little as opposed to the other usable parts of the spectrum
maybe thru the design of genetics something the plant needs very little of like the orange to red as indicated by the graph
the plant uses much less energy to obtain it.
just a thought.
but even *if* a fool thought that red is much better, needed or prefered more because its easier to absorb,
then explain why a plants in veg under say a very blue 7500K bulb thrive with NO RED?
again
easier to absorb red spec. that that pants needs much less of compared to what it takes in way more of doesn't equal its better.
if so explain *exactly* how and why its better other than opinion?

you have diarreah,
your spending way less energy expelling water quickly as opposed to a big solid hunk of semi dry mass that take more energy physically and takes longer to push out.
does that mean were better off having diarreah?
even a fool know's that answer

 

[RB56]

Plants also need an adequate amount of green light. Green light should also provide for more penetration and even lighting.
- http://pcp.oxfordjournals.org/content/50/4/684.full
- http://hortsci.ashspublications.org/content/39/7/1617.full.pdf+html

Whether you want to pay for it or not, is up to you. RGB, essentially equals white light. I'm not certain, but I think the orange light given off by HPS, is a byproduct of the sodium plasma reaction(ie: all HPS lamps are predominantly orange). At lower relative energies, the Philips DE HPS lamps do provide most of everything...at lesser visibility, which important for me.

Neither of those linked documents say that. The second is concerned with the impact of a proven red and blue LED growing system on the mental health of future astronauts. They propose a theoretical growing benefit from adding green light but state there is no evidence to support the idea.

You are contradicting the information in the link you provided from Phillips. Why not support your contradictions instead of adding more links?

 

[rives]

Is it possible to conclude from this anything but that 1KW red biased HID is going to provide more energy for photosynthesis than 1KW MH? Possibly more efficiently? Or they could be lying

I'm assuming from the bulk of your posts that you are considering HPS as being the "red biased HID". From the following SPD charts, which lamp appears to have a greater percentage of red in it to you?

[FONT=Arial, Helvetica, sans-serif]Philips CDM Elite Agro 315W[/FONT] -

 

[Drek]

Neither of those linked documents say that. The second is concerned with the impact of a proven red and blue LED growing system on the mental health of future astronauts. They propose a theoretical growing benefit from adding green light but state there is no evidence to support the idea.

You are contradicting the information in the link you provided from Phillips. Why not support your contradictions instead of adding more links?

RB, are you seriously in that much denial? They propose exactly that.

Paper one:
"Because green light can penetrate further into the leaf than red or blue light, in strong white light, any additional green light absorbed by the lower chloroplasts would increase leaf photosynthesis to a greater extent than would additional red or blue light."

Paper two:
"The addition of green light in combination with red and blue LEDs may promote increased plant growth, since green light can penetrate into the plant canopy better than red or blue light (Klein, 1992; Smith, 1993)."

"The plants with the greatest leaf area were grown under RGB, followed by RB and CWF, and then GF. The specific leaf area of the GF treatment plants was the highest among the treatments, followed by RB and CWF, and then RGB. The RGB plants also had the greatest shoot fresh and dry weights with the RB and CWF, and then GF treatments following in descending order. The photosynthetic rates were lower in plants grown under GF and there was no significant difference in chlorophyll content among treatments (Table 2). Leaf area index and CGR were decreasing in the order of plants grown under RGB, CWF, RB, and GF (Fig. 2)"

 

[Drek]

I'm assuming from the bulk of your posts that you are considering HPS as being the "red biased HID". From the following SPD charts, which lamp appears to have a greater percentage of red in it to you?

View Image

[FONT=Arial, Helvetica, sans-serif]Philips CDM Elite Agro 315W[/FONT] -

View Image

ie: red

In relative energy terms, it's more...in output it's less.
I'll take the lower power, higher relative energy output.

 

[rives]

ie: red

In relative energy terms, it's more...in output it's less.
I'll take the lower power, higher relative energy output.

Probably true, but overall output is irrelevant when considering color bias - it only refers to the proportions of various colors within a given lamp's output.

 

[RB56]

I'm assuming from the bulk of your posts that you are considering HPS as being the "red biased HID". From the following SPD charts, which lamp appears to have a greater percentage of red in it to you?

View Image

[FONT=Arial, Helvetica, sans-serif]Philips CDM Elite Agro 315W[/FONT] -

View Image

It was definitely an error to assume the red appearance of HPS light lines up with the red frequencies we are apparently looking for. The Philips CDM Elite Agro 315W appears to have the higher percentage of red.

I don't mean to be arguing for any lighting technology. I'm trying to answer an essential question: what is the absolute minimum we can provide the plant that will meet 100% of its needs? I don't think there is any evidence that this is the entire EM spectrum at a sufficient level to drive 100% of the photosynthesis the plant requires for optimal growth.

It appears that red light is best for photosynthesis. Can 100% of the need be met with just red light? A very efficient solution may lie down that road.

We know that plants can use other than red light for photosynthesis. Chlorophyll B likes blue light. Chloroplasts deep in the leaf may be able to use green light. Are these redundancies for conditions that are less than ideal or do all levels of efficiency and redundancy have to be firing to get the job done?

Is there any evidence that light wavelengths trigger hormonal responses? Guess that's another question, but it sort of fits into the first.

 

[Drek]

Probably true, but overall output is irrelevant when considering color bias - it only refers to the proportions of various colors within a given lamp's output.

Yes, I agree with that, and that's exactly what I'm saying.

I'd take the 315 Agro.

 

[Drek]

Relative energy matters because (some) plants use more red (in theory) in a complete lifecyle. Power also matters tho, imo.
Bigger stuff should require a little more oomph...at the right spectral distribution. But aside from all this (and not aimed at anyone in particular), I'd don't really care about arguing about
how much of a spectral band a certain plant uses...as much as having a large amount of everything available for it to use. Red makes up the majority of the Sun's useful PAR, but it doesn't at all
negate the importance of the other spectral bands, imo.