Why has there been no major advances in HPS bulbs?

[Doc420]

Lumens are for humans.
All those bulb manufacturers with Chinese crap they dont even have a output in µMol.
The bulbs without µMol is made for streetlighting.
The µMol/PAR output is the horticultural way for measuring bulbs for over 7 years.
Any company that doesnt release this information is a hype company.

The standard measurements of light output have traditionally been done through the foot-candle, lumens and lux. They quantify how humans experience the intensity of light, based on the limited sensitivity of the human eye in the yellow/green area of the spectrum (around 550 nm). Plants however use a much wider spectrum for photosynthesis, called the PAR spectrum (Photo-synthetically Active Radiation), ranging from 400-700 nm

Human eye sensitivity versus plant sensitivity

Photosynthesis is not driven by brightness of the light according to the human eye or the energy of a photon (which varies for different colors) but purely by the number of photons in the PAR spectrum. You need about eight photons to bind one CO2 molecule. So to quantify potential photosynthesis it is all about the number of photons within the PAR spectrum hitting the plant. This is expressed as Photosynthetic Photon Flux (PPF – total photons emitted from a light source per second) and Photosynthetic Photon Flux Density (PPFD – the number of photons hitting one square meter of surface per second) and it is measured in moles or micromoles (µmol) of photons.

You can measure the number of photons hitting your plant (PPFD) using a quantum meter, predicting the potential photosynthetic capacity of your light.

You can measure the total number of photons emitted by a lamp (PPF)by putting it in an Ulbricht integrating sphere

So where we used to have luminous flux in lumens, we now have PPF in µmol/s, and where we used to have illuminance (light indicent on a surface) in lux, we now have PPFD in µmol/m2/s

Lamps with high lumens output are not necessary high par output lamps: some lamps with lower lumens output have higher micromole output.

Another important issue is of course the spectrum of a lamp. Micromoles alone is not enough - or blue and red LEDs would have worked

Doc

 

[TruthOrLie]

If you take a $20 HPS bulb and do a side by side with a $200 HPS bulb, whats the difference?

More trichomes? Fatter nugs? Longer life? Anyone have a comparison thread for me to check out?

I've only used a CMH and an HPS eye that a friend gave me.

I bought a $20 hps and it looked way different than the eye did when it wasn't turned on...

but the light elements looked about the same size. Never fired the cheap one up though

 

[squarepush3r]

CAP Digilux is 155,000 lumens, has good plant spectrum, and designed for digital ballasts. I'd say thats a fairly significant advance recently

 

[growcodile]

I noticed whilst searching info that osram are made in germany while phillips are made in china lol think i may try the osram .A

well not really true for all, i bought some osram 600w nav-t 4y super hps that were done in hungary

 

[Doc420]

CAP Digilux is 155,000 lumens, has good plant spectrum, and designed for digital ballasts. I'd say thats a fairly significant advance recently

Lumens???? the question is:what is the µmol output!!

 

[sm0k4]

CAP Digilux is 155,000 lumens, has good plant spectrum, and designed for digital ballasts. I'd say thats a fairly significant advance recently

After a search I cannot find any info on these bulbs. Not a reputable manufacturer IMO. Probably more Chinese junk. How is this an advancement? What makes the bulb better? How long does the 155k lumen output last and what is the PAR range and umol output?

http://www.4hydroponics.com/manuals/DigiluxSpecSheet.pdf

This is an example of a piss poor datasheet. They even got the spectral graphs backwards for the enhanced bulb output. Looks like a Chinese knock off. Probably will grow well, but is it worth $100 when you can get a bulb that costs less than half that?

 

[Mr.Tortoise]

http://www.apogeeinstruments.com/quantum/ for ppf meters. Cheapest looks like 160. Haven't had time to look at them.

 

[Doc420]

Here some real info as a benchmark.

400w
1. Philips Agro 400w 230v 660 uMol (output stabile, extra blue spectrum)
2. Philips Greenpower 400w 230v 725 uMol (output stable)

600w
1. Philips SON-T plus 600w 230v 1045 uMol (output "unstable") output degrades fast
2. Philips SON-T Greenpower 600w 230v 1100 uMol (output stable)
3. Philips SON-T Greenpower 600w 400v 1150 uMol (output stable)
4. Philips SON-T Greenpower 600w 400v EL* 1170 uMol (output stable) *specialy for high frequency electronic ballast >100.000 hertz

1000w
1. Philips SON-T Greenpower 1000w 400v EL* DE 1925 uMol (output stable) in reality the lamp gives 2100 uMol at the start of its lifetime.
*specialy for high frequency electronic ballast <100.000 hertz

 

[asde²]

good post. there is barely a company who offer as much information as philips does - you can even contact them and ask how much light you would need to grow decent nugs (yes they will also answer to horti related questions - they have some huge ass horticulture department unlike osram who use 3rd party companys for this - and unlike the other pure horticulture companys, they offer 5x more SERIOUS! data without outrageous claims)

and btw; my philips bulbs are made in belgium too.. no chinese (even tho i guess, for companys like philips/osram it wouldnt make a difference where they are produced. they will be most likely same quality anyways!)
also if you take a look at philips/osram digital ballast you may find out that those are far better than the www advertised super ballasts for a quadrillion dollars. - if you wanna waste so much money for you light, just invest in serious LEDs instead of wasting your money on HID lighting companys selling their products for 200x the price its worth to pay.

 

[whodair]

philips son agro 430w is a little beast !! its got what ladies like !!

 

[SmokinErb]

I know this is sorta off topic, but I didn't want to start a new thread when this one is basically heading the direction I was looking for.

What would you guys say is the best bulb for growing, for quality, not quantity? I typically run with CMH bulbs, however due to the need to go stealthy, I was considering an 8 lamp T5ho fixture. However, stealth needs aside, what would be the best bet? I still think CMH, but this definitely isn't my field of knowledge. MH possibly? How do T5's stack up (penetration issues aside, SOG is the method?)

 

[Pompey_Monkey]

CAP Digilux is 155,000 lumens, has good plant spectrum, and designed for digital ballasts. I'd say thats a fairly significant advance recently

Wow - look at the funky boxes! They must be the dogs bollocks of growlamps!

 

[Doc420]

This Philips 1000w greenpower growlamp has the highest uMol output and a special spectrum designed for plant growth.
Specially build for electronic ballast that run more than 100.000 hertz.

 

[chefro420]

Philips is working with Cornell University. I was talking to a local farmer who is doing a study with them. Philips had designed a new ultra efficient reflector. He was telling me they have the lumen output equal to a 600w , but only uses 380w. Tried to find info online , but couldn't dig anything up

 

[TruthOrLie]

they didn't hear about the benefits of vertical growing yet, or what?

 

[Doc420]

I think that a combination between MH and HPS gives great results.
Also hps with metal halide plasma sounds like a great combination.

 

[spurr]

lumens give lux. Why is the term lumen bad? I think it is the end user's responsibility to know how to interpret the data given.

spectral efficiency might be a better term for HPS and why their lumens aren't weighed as high as a light tailored to the optimal spectra for growing.

Using lumens or lux to judge a lamp's radiance and irradiance (respectively) for growing plants is bad because both of those measurements weight green light in PAR range much higher than blue and red because green is the most used spectrum for human eyes. Lumens and lux are light measurements for human eyes.

Here is an image of lumen spectral weight for human eyes vs that of an average (near) ideal spectrum for higher plants from the effect of photons on photosynthesis per wavelength. In the image below the bell shape line (V) is how lumen and lux meter weight and report PAR range photons; the other line (P) is K.McCree's 'Action Spectrum of Photosynthesis' (ASP). The bell curve line is how human eyes use light to see (higher means more efficient usage) and the other line is how most plants use light for photosynthesis:

All wavelengths in PAR range have considerable "quantum response", i.e., ability to dive photosynthesis. The difference between blue, green and red photons (as well as violet, orange, yellow, etc.) is not large; thus using unweighted (equal) quanta (photon) measurement in PAR range is best for plants. One can then use the SPD of the lamp relative to K.McCress Action Spectra of Photosynthesis to judge what lamp is 'best' for plants. In the image below the flat/square line is that of an ideal "quantum response" (unweighted) of a quantum sensor used to measure incident photons for plants (irradiance). That is, a meter to measure light for plants gives equal weight (efficiency) too all photons within all wavelengths in PAR range. In the image below K.McCree's ASP (called "Average Plant Response") is also shown:

In the three graphs below one can see three different methods of measuring light: that which leafs absorb (1st graph); incident photons relative to photosynthesis (2nd graph); and quantum yield of wavelengths from K.McCree's work, i.e., his ASP. We should use graph C, from K.McCree's ASP when judging the SPD of lamp in terms of the lamp's ability to drive photosynthesis:

Here is the quantum response of the quantum sensor I use relative to the ideal (unweighted) quantum response for plants:

To sum it up:
We should not use lumens or lux because they measure green light much more than blue and red; thus the reading from a lux or lumen meter does not show us what the plant is really getting that it can use for photosynthesis. Lumens and lux grossly under-value the light plants are getting that they can use for photosynthesis. Using a quantum sensor to measure umol/area/second in PAR range (400-700 nm) shows use the actual amount of incident photons the plant is getting; thus using microMoles (umole) via a quantum sensor is the much better option.

If you have further questions please feel free to ask

@ all:

IMO the best HID lamps out now are Digilux HPS and MH; and Ushio as a second chioce. Both brands are made for digital ballasts unlike Hortilux lamps. I have a 1,000w Digliux HPS and 1,000w Digilux MH I will be testing with my Galaxy select-a-watt ballast next week using my Li-cor quantum sensor. The quantum sensor I use has a very near ideal quantum response and it's far, far better than using lumens or lux for the reasons I stated above.

The SPD from the Digilux MH is really nice, albeit it has a bit more green than I would like (relative to blue). And the SPD from the HPS is really nice too, it is comparative but better than the SPD from Hotrilux Eye and Oshiu Opti-red, IMO.

The irradiance by lumnes of the Digilux lamps are very high (1,000w MH - 120,000 lumens and 1,000w HPS = 155,000 lumens), higher than any other 1,000w I know of, IIRC. That should equate in to higher umol/area/second when looking at the SPD of the lamps (ex. PPFD; "Photosynthetic Photon Flux Density" as umol/meter^2/second).

 

[spurr]

I wish Phillips would come out with a 1000 watt Ceramic Halide Bulb, it would have a wicked light spectrum. I wonder why they can't produce one bigger then 400 watts?

AFAIK it has to due to with safety; a 1,000w CMH would be like a pressure bomb waiting to blow up. I could misunderstand the science behind the CMH, but like I wrote, AFAIK it has due to with excessive pressure inside the lamp to make a 1,000w CMH. That is why we have not seen, and probably will never see a 1,000w CMH.

 

[spurr]

Until meters that measure PAR are in every hydro store for $20, Lumens are the de facto measurement for people to compare. It wouldn't matter if YOU have a PAR meter, as you wouldn't have shit for data to compare to. We use lumens because we all use lumens. I know it's not perfect, but until the forementioned happens, it is the standard.

Hey there Lazy,

I agree about most people not willing to buy what they should buy to measure light for plants, sadly. But I don't think that means we should settle for lumens or lux. I plan to compile a large data set of umol measurements using my quantum sensor (older term is "PAR sensor") for many different lamps, ballasts and reflectors. With those data other people can use them as a template to find the (near) ideal placement for their setup, if they use the same lamp/s, reflector/s and ballast/s I plan to test. This will take some time, but it's something I have been planing for a while.

For a good quantum sensor one needs to shell out ~$460 (Licor LI-190SA) and an additional $600 or 1,400 for a light meter (Licor LI-250A) or data logger (Licor LI-1400), respectively. One can buy a used Licor LI-1000 data logger for ~$100 that works just fine, so the total would be ~$600 for the quantum sensor and data logger.

Either of the cheaper quantum sensors, the Apogee or SpecMeter brands, are not worth their cost (~$300 and ~$200, respectively) because their quantum response is very poor.

It's true that lumen and lux meters measure PAR range light just like quantum sensors, but the units of measure are different as are the weights given to each wavelength (as I posted above).

For cannabis we want at most 1,500 umol/area/second; that has been proven in at least four studies to provide the highest rate of photosynthesis (as PPFD; Photosynthetic Photon Flux Density, i.e., umol/meter^2/second). With this topic it's also important to point out umol/area/second is used to find DLI (Daily Light Integral); but DLI is too far off topic to write about here, I think.

For cannabis >100,000 lumens has been found to have highest rate of photosynthesis (in one older study). But the flaws with using lumens makes the results from that study unusable (because we do not know the SPD from the light they used).

 

[spurr]

In horticulture we use for luminous flux photosynthetic photon flux (PPF) measured in micromoles per second for instead of lumens and for illuminance photosynthetic photon flux density (PPFD) measured in micromoles per square meter per second instead of lux. Hence the per second, you can calculate the total light sum.

Quoted for truth; however, for indoor gardens I like to not be limited by PPFD (re meter^2) because many canopies are not that large. I like to use both umol/area/second and umol/meter^2/second to offer greater flexibility in irradiance (aka illuminance) reporting. Indoors, unlike under the sun, the incident photon foot print from a reflector is not homogeneous, so one needs to take many measurements with the quantum sensor to find an average that offers sufficient accuracy for the canopy total.

Well there is a solution for that already: the double ended lamp as doc mentioned. Perfectly aligned with the reflector and gas filled to lose its heat more efficient.

One reason I dislike those combo style lamps, e.g., 600w HPS + 400w MH, is they will not provide nearly as homogeneous SPD over the caonpy (e.g., due to reflective issues, diffuse vs direct photons) verses a single lamp like a 1,000w MH or 1,000w HPS. That and they have considerably lower radiance than a 1,000w HPS and even some 1,000w MH like Digilux lamps.