CFL's (again)

[Pure]

I never would have believed that there was so much controversy about light types.

 

 

Believe it , you will always have people trying to get a foot up on HID lighting , mainly because the cost of it running is probably if not the most expensive part of the room to keep running ( inc nutes ect ) and the heat it causes also means we have to look into better ventilation which once again means more $$ ( but this time just a one time outlay ).

 

I have looked at the figures on various options and LED's probably hold the most compelling argument imo, however to match your HPS you will end up spending triple what you do on purchasing your HPS , and then ontop of that you will be constantly adjusting thousands of leds' as they must be pretty close to touching the plant at all times to be most effective.

 

With that said abut LED's all of the possibilities i speak of are hypotheticaly based from what you can do with an led it is not however based off of any grow tests , of all the LED grows i have looked at I have NEVER seen a cola come from an LED crop that has compared to one from HPS lighting. Not to mention HPS is just a whole lot less fuck around

 

It goes as far as really upsetting some folk.

 

Not the topic that does it, it is the way it is handeled and viewed by some of the participants

[Pam]

My Leige,

Let us pray that the subject of LEDs does not kindle yet another bale fire.

I have found LEDs useful in adding spectral color but only in addition to other lighting.

There was a time when I had high hopes that these would be a boon to growers, having

witnessed the brightness of the LEDs called "wall washers"; those that can light up the entire

side of a tall building with intense color. They are long lasting and cost a pittance to run as they use

barely any power.

As for my reaction to past comments in this thread, I would beg your pardon for doing

the usual female thing by lumping past insults and insinuations together with the current slew,

and perhaps over reacting. I am however still unable to view the comment "Notice what I didn't

say" as anything other than antagonistic. And I can't seem to read the other comments in any tone

other than one meant to insult me by insinuating my incompetance. I believe that, had I written

something to bring on such an attack, my reaction would have been different, however my

comments were completely innocent. and meant only to add information to the topic.

I am grateful for your patience and even tempered responses to this rather ugly exchange.

In the future I shall be more careful when adding to a topic so as not to inadvertantly cause

an argument.

Gran

[Al B. Fuct]

umm, I don't know if I've done something wrong here, but my lux meter tells a different story to this. With one (new) lamp lit above a luxmeter (tecpel 530) @ about 50mm it's reading 80ish, with the second lamp (used about 6 months) lit up next to it above the lux meter it's reading 140.....

 

So adding another lamp right next to the original and not moving the meter increased the lumens per sq meter (lux)....

 

That's not what mine does. A lux meter measures intensity of the energy 'pushing' the photons from the source, not the number of photons.

 

If you don't get more lumens by adding more light sources then what does a lumen measure?

 

Intensity of the light discharge. More low intensity sources does not increase the intensity of any of them.

 

If adding more light fixtures in a given area doesn't give me more lumens why would I bother with a 600w lamp vs a 400w?

 

Greater intensity of light discharge.

[Al B. Fuct]

Hi Luke Skywalker,

 

Interesting post.

 

I think that what AL B. was getting at is this : If say there was a radio station that outputted at 1000 watts.

 

Now, let's say that you, some distance away could only just recieve it.

 

Ok, now,lets build another 1000 watt radio station beside it and have it broadcasting the same stuff.

 

I guess that you, some distance away would not notice any difference, the strength of that signal would not change.

 

The range of 1000watts would not change no matter how many transmitters there were.

 

A 2000 watt radio station would however have a much greater strength and range, wouldn't it ??

 

There's far more variables in an analogy employing radio signals, up to and including the frequency of the signal and the time of day.

 

However, generally speaking, a pair of 1000W radio transmitters, with antennas side by side, both on the identical frequency (and in phase), would have the range of a single 1000W transmitter. Why? Because the range is influenced by the maximum amplitude of the signal fed into the antenna. You might have 2 xmtrs side by side, but neither is causing the amplitude of the other to increase. Sound familiar?

 

A 2000W station will be 3db stronger than a 1000W station at any given distance within their ranges.

[Al B. Fuct]

For instance, why would you have dual batten fluoros if it didn't put out more light than one?

 

To cover more area, if from only slightly differing angles due to the adjacent positions of the light sources.

 

Pure said it best a few posts back, about putting two separate light sources within the same physical space. However, in the radio signla analogy, that's actually possible. You can couple two RF signal sources into a single antenna (using a diplexer) and get that very effect.

 

Paralleled radio transmitters with a single antenna work a bit like paralleled batteries. A pair of RF sig sources would induce 2x the current into the antenna element but not double the voltage.

 

*looks around for Al*

 

I'm around; it's just harvesting time again, as usual every 2 weeks. I only have short bursts of time to put in at the moment.

[Biatch]

At the risk of continuing this thread ad infinitum....may I ask, what is the difference between the Cfl's lamps that "Granny" mentions and "ordinary made for home" Cfl's?

 

Is it just "brightness and temperature" or something else ?

 

Would a "household type lamp" have anything on it to identify it as such..?

 

 

Would you put these up in ur kitchen?

 

 

Grow people grow. Keep the THC lines going.

[ilky]

Hi, thought I'd break my forum virginity on this controversial thread

 

I've been doing quite a bit of research lately on the subject of efficient lighting. Am currently conducting some experiments with high-brightness LEDs, proof of concept shows its worth persuing. Am really interested in what LEDs you are using Granny (wavelength, W/m^2 (if provided), Vf (forward voltage), and If (forward current))?!

 

OK, now about light:

 

http://en.wikipedia.org/wiki/Visible_spectrum

The most efficient light source for plant growth would look pink to humans. Plants dont respond much at all to the green band of the spectrum so any power put towards that band is largely wasted. Because of their narrow bands and high efficiency (near 100% of power is converted into light), LEDs are the better lightsource. Only thing currently limiting the use of LEDs is cost, lack of pre-made products, and lack of variety in peak wavelengths.

check this: http://www.ledgrow.eu

 

http://en.wikipedia.org/wiki/Photometry_%28optics%29

Luminous flux is measured in lumens, which we care about.

Radiant flux is measured in watts, which we care about.

Irradiance is measured in watts/m^2, which we care about.

Spectral irradiance is measured in watts/m^2/Hz, which is what we should really care about.

Luminous intensity is measured in candela, which we dont care about.

 

http://www.onlineconversion.com/illuminance.htm

1 footcandle = 10.76 lux = 10.76 lumen/m^2

 

http://en.wikipedia.org/wiki/Foot-candle

Footcandles are measurements for the visible spectrum for humans. The bulk of light our eyes respond to is in the green bad of the spectrum (that's why eyes tend to be pink - even though they dont look it on the outside), plants "see" mostly in the blue and red bands of the spectrum. So footcandle derived comparisons are far from accurate and should be avoided. For growth, the Photosynthetically Active Radiation (PAR) should be measured (usually in microEinstens). And this is the tool to do it: http://www.specmeters.com/Light_Meters/Qua...ight_Meter.html

[WantDaChronic]

what a great way to lose your ozstoners posting virginity ilky, well done

[Gazza2001au]

i fiannly got around to taking a picture of the light meter its around 15cm away from the 130w cfl as u can see its reading 3000 lumens it aint no technical light meter but it works