Do lumens really matter? Do they add up? Lighting experts apply within

[mj320002]

Yeah so lumens aren't really a good measurement of how good a light is at growing. We already knew that and that was a nice little read Jimmyc.


That article however doesn't really address whether or not light adds. Even though we are talking about lumens adding the same thing seems to apply to light in all spectrums including PAR. I think the place the disagreement comes from is we are thinking about the question differently. Some people say it does because the light volume increases so you can cover a larger area with more bulbs. The ones who say it doesn't myself included are saying that it doesn't add because the light isn't actually brighter at the source.

In order to make this information useful we need to know how much light and in what specific spectrums an mj plant can use. PAR is useful but that article also spoke of accesory pigments which are beneficial as well. I personally think this is where LED's fall short. Currently they are too limited in the spectrums being produced along with a possible lack of intensity. Not because they can't produce the spectrums but because people are focusing on to narrow of spectrums.

I think I might have rambled a bit but I hope you get what I'm saying.

Whoa, I left this thread for 12 hours and suddenly there are all kinds of answers! Hooray!

Just for stopping by, everyone gets a +rep (oooooh, aaaaaaah)!

Anyway, I read that other thread, jimmyc, and I must admit the part with the charts and graphs was a little over my head. I haven't had my morning coffee yet, so I'll revisit it when I'm closer to fully awake than I am now.

Someone there says that floros have the most usable light for plants? I can only hope this is true, as I'm a floro lover and have been looking for any excuse to purchase additional bulbs!

Someone there also says that a lower lumen rating on a bulb is indicative of a better light for plants? Something rings true about this to me. since "lumens are for humans" (teehee), and measure more of the green light than anything else (which plants can't use) it seems to make sense that a lower lumen output bulb probably has more light in the blue and red ends of things which is what plants use.

Now, I'm also under the impression that LED grow lights typically don't even offer up their lumen output, and If you've ever seen LED grow lights in action you'll know that they don't appear "bright" in the way we expect from a grow light. Here's a quote from an LED related site:

The most accurate unit
of measurement for comparing grow lights is the micro Einstein, which measures how many photons of light strike an area per second

Then they go on to say that all types of grow lights (except the ones they sell, of course) emit large amounts of unusable light.

Does anyone know what the lumen output of an LED grow light is? Has anyone seen a successful grow that used only bulbs with a low lumen output (13W CFLs, for instance)?


EDIT: I've given out too much rep in the past 24 hours... how long do I have to wait before I can hand out more?

 

[fish601]

the sun seems to work well for me.. who would of thought?

 

[mindphuk]

In order to make this information useful we need to know how much light and in what specific spectrums an mj plant can use. PAR is useful but that article also spoke of accesory pigments which are beneficial as well. I personally think this is where LED's fall short. Currently they are too limited in the spectrums being produced along with a possible lack of intensity. Not because they can't produce the spectrums but because people are focusing on to narrow of spectrums.

I think I might have rambled a bit but I hope you get what I'm saying.

No, you said it perfect. This is something I brought up in one of the LED threads. I think that an LED array may need to have 3, 4 or even 5 different lamps to cover all of the spectrum necessary. However, even if we can find the right combination for flowering is found, the next hurdle is intensity. I think most people use at most 5w per lamp. If that can be bumped up to maybe 10 or even 15w, maybe we can finally see some nice buds.

 

[mindphuk]

Mindphuk is another person who makes up bullshit, and doesn't have a clue. He's on my ignore list.

You are so full of shit. You haven't shown one thing I said was incorrect. Talk is cheap, why don't you back it up with something substantial. I'd really love to see where I said something incorrect wrt physics.

 

[bigtomatofarmer]

Thank you tea tree oil for trying to help these stoners.


But sometimes a picture is worth 1000 words

Also, remember that High Pressure Sodium is the most efficent bulb on the market. Well, except LED.
But still, it is more efficent in $$$, and has better light coverage.

Approximate light production:
Incandescents: 17 lumens/watt
Mercury vapor: 45-50 lumens/watt
Fluorescents: 60-70 lumens/watt
Metal halide: 90 lumens/watt
High pressure sodium: 107 lumens/watt

 

[TeaTreeOil]

Wow. Imagine that. You say someone is full of shit, when they're obviously full of shit, and the post vanishes. While the bullshit remains....

This site is a detriment to all horticulture.

 

[mindphuk]

Wow. Imagine that. You say someone is full of shit, when they're obviously full of shit, and the post vanishes. While the bullshit remains....

This site is a detriment to all horticulture.

Yes, too bad they try to keep it civil here and won't allow unprovoked personal attacks on this board. Imagine all the fun we could have.

 

[fenderbender1201]

a good way to get GREAT light on a plant that ive found recently is to build a screen around a CFL bulb and keep in milimeters away from the bud site

the screen keeps all vegetation from hitting the bulb, and keeping the great light output of a CFL.


i imagine a screen on multiple bulbs all around the bud sights mm's away would be much more effective then any HPS light... no?

 

[doobnVA]

Thank you tea tree oil for trying to help these stoners.


But sometimes a picture is worth 1000 words

Also, remember that High Pressure Sodium is the most efficent bulb on the market. Well, except LED.
But still, it is more efficent in $$$, and has better light coverage.

Approximate light production:
Incandescents: 17 lumens/watt
Mercury vapor: 45-50 lumens/watt
Fluorescents: 60-70 lumens/watt
Metal halide: 90 lumens/watt
High pressure sodium: 107 lumens/watt

Now I'm confused again. Didn't we already decide that lumen output has no bearing on how good the light is for plants? If that's the case, then a higher lumen per watt bulb isn't necessarily the best bulb for growing plants, right?

 

[110100100]

Now I'm confused again. Didn't we already decide that lumen output has no bearing on how good the light is for plants? If that's the case, then a higher lumen per watt bulb isn't necessarily the best bulb for growing plants, right?

Right, lumen have nothing to do with how a plant sees light.

 

[jimmyc]

Some clearing up is in order evidently. No, light does not 'add'. Adding more bulbs to your garden will only help to ensure that more area gets what ever wattage you want. For instance, if you have a 400 watt HPS in a 8x8 area you can be sure that not all of that 64 square feet is getting 400 watts. However if you add another 400 watt HPS you don't now have 800 watts, you have 400 watts over a larger area.
As for HPS being the most efficient bulb well that just plain false again as is explained in another post I made to this forum, Ceramic Metal Halide is actually the most efficent. It's only draw back is wattage, Phillips currently only makes 400 watters but is in the process of retrofitting a few factories to make higher wattages.

 

[sweetsmoker]

As for HPS being the most efficient bulb well that just plain false again as is explained in another post I made to this forum, Ceramic Metal Halide is actually the most efficent. It's only draw back is wattage, Phillips currently only makes 400 watters but is in the process of retrofitting a few factories to make higher wattages.[/QUOTE]
i have purchased a 4 x 250w cfl hood, this light is 100% p.a.r and can be lowered to within inches of the plants,, was wondering if this would be considered better than a hps due to these factors, or do u believe a hps wud outshine this unit... if like myself u believe the hps 2 be better, then surely it is the photons that are more important to the plant than par as hps has more photon output but only 15% par. mmmmm just another spanner in the works for us all 2 contemplate wat u lot think... im gunna giv it a go anyways and find out here a pic of the unit

 

[mindphuk]

Some clearing up is in order evidently. No, light does not 'add'. Adding more bulbs to your garden will only help to ensure that more area gets what ever wattage you want. For instance, if you have a 400 watt HPS in a 8x8 area you can be sure that not all of that 64 square feet is getting 400 watts. However if you add another 400 watt HPS you don't now have 800 watts, you have 400 watts over a larger area.
As for HPS being the most efficient bulb well that just plain false again as is explained in another post I made to this forum, Ceramic Metal Halide is actually the most efficent. It's only draw back is wattage, Phillips currently only makes 400 watters but is in the process of retrofitting a few factories to make higher wattages.

Even though 2 400w lamps don't give the same output as an 800w, where the two overlap, there will be an increase in light energy. This was proved very early on that light acts like waves and that you can even get interference patterns when the two point light sources combine, the crests are bigger and the troughs cancel each other out.

This is very easy to demonstrate with a lux meter. The area of overlap is brighter and registers more lux than a single lamp will produce at a given distance.

 

[TeaTreeOil]

Some clearing up is in order evidently. No, light does not 'add'. Adding more bulbs to your garden will only help to ensure that more area gets what ever wattage you want. For instance, if you have a 400 watt HPS in a 8x8 area you can be sure that not all of that 64 square feet is getting 400 watts. However if you add another 400 watt HPS you don't now have 800 watts, you have 400 watts over a larger area.
As for HPS being the most efficient bulb well that just plain false again as is explained in another post I made to this forum, Ceramic Metal Halide is actually the most efficent. It's only draw back is wattage, Phillips currently only makes 400 watters but is in the process of retrofitting a few factories to make higher wattages.

Light adds. I proved it a few posts ago. Work on your reading comprehension.

 

[TeaTreeOil]

Even though 2 400w lamps don't give the same output as an 800w, where the two overlap, there will be an increase in light energy. This was proved very early on that light acts like waves and that you can even get interference patterns when the two point light sources combine, the crests are bigger and the troughs cancel each other out.

This is very easy to demonstrate with a lux meter. The area of overlap is brighter and registers more lux than a single lamp will produce at a given distance.

OH YOUR GOD! You finally see the light.

 

[mindphuk]

OH YOUR GOD! You finally see the light.

I really think you have me confused with someone else. Our disagreement was the properties of aluminum metal such as in a reflector vs. aluminum foil. I have never held any other position on light and was one of the first ones in one of your early posts about light to recommend to the doubters to buy a cheap light meter.

As any good scientist knows, vigorous debate and defense of ones position is fundamental to progress. I have been at conferences where it looked like fistfights would break out. However, I have never refused to listen to what a colleague has to say and would never consider someone worth of ignoring if they disagreed with me. You may not remember, but I repped you early on when you first joined, there are many topics we agree on. I really think you were being quite childish when you decided you had to ignore me because we didn't see eye-to-eye on a single topic.

 

[jimmyc]

I was under the assumption they would be inline and overlap would be minimal. It would stand to reason that light overlap would be a bother to any grower because they cause irregular canopies. Not to mention if you're looking for more light through light overlap just get a higher wattage. Cermaic Metal Halide for the win over High Pressure Sodium!

 

[bigtomatofarmer]

I read your other thread about ceramic metal halide, but I failed to see where you mentioned the watt/lumen output???

I understand your point about a wider spectrum range, but my electric company charges by the watt.

Also, how often do those CMH bulbs go out? My HPS has been kickin for 2 years now. Actually, Im glad you reminded me, I should change that sucker out haha

 

[plutomoney]

Thank you tea tree oil for trying to help these stoners.


But sometimes a picture is worth 1000 words

Also, remember that High Pressure Sodium is the most efficent bulb on the market. Well, except LED.
But still, it is more efficent in $$$, and has better light coverage.

Approximate light production:
Incandescents: 17 lumens/watt
Mercury vapor: 45-50 lumens/watt
Fluorescents: 60-70 lumens/watt
Metal halide: 90 lumens/watt
High pressure sodium: 107 lumens/watt

Let me get you pic right 50000/10=5000
5000/54=92.6

so its 92.6 lumens per watt for a t5ho ist that more than the Mh or is that a typo in the pic

 

[plutomoney]

i would love to have a nonceramic mh bulb thats 50k lumens i think a mh salemans made that chart