Home of the Old Fart's Club

[umbra]

Wow, nice umbra, 4 weeks veg? how tall are they?

a little over 2 ft. actually had to kill a dozen or so plants because they just wouldn't fit into the space. While I reduced the number of lights from 8 to 6, I increased the foot print and the PAR ( the amount of usable light ) substantially. I put a couple of sick plants in there to veg and they are monsters.

 

[DirtyDiana]

Just beautiful Umbra! I hate when you have to kill a plant, but sometimes it's necessary. They ate the perfect size for going to flower.

 

[Keef]

Morning O.F.C. !--Again !-

Bud -- If U don't have the patience of an elephant this genetic doubling is not for U !-- U could have perfect technique and still never be successful !--- If your clone skills aren 't up to par then you'll fail !-- This is not a formula and if U follow it exactly U will succeed! -- This is more like fishing !

Umbra !-- Sorry about the ignorance !-- It is a medical condition and if U seized in front of me you'd be just fine !-- What causes it is a mystery! -- Others may not understand but to U got a Muse ? -- Recover from the seizure and see things different ?-- Will a strobe set of a crisis ?-- Do U have a trigger !

 

[umbra]

LED lights require new thinking about the way we measure light for use by plants. The typical rating most growers are familiar with is the “lumen.” The definition of the lumen is the total light produced within the range of the human visual response. It tells us nothing about the distribution of that light energy over the spectrum, and most importantly, it doesn’t tell us how much is useful for plants.

The problem with lumens is especially pronounced when measuring light at the far ends of the human visual response curve. Consider three lamps—red, green and blue—each emitting the same number of watts of optical energy. The red and blue lamps would have much lower lumen ratings compared to the green lamp, simply because the human visual response is very low at red and blue, and highest at green. That’s why a high lumen rating does not necessarily make a lamp better suited to growing plants.

Similarly, light meters that measure in “lux” tell us very little about a lamp’s plant-growing power. The light sensors in lux meters have their own spectral response curves which may over- or under-measure light at various colors. This is why lux meters usually have different settings for “sunlight,” “fluorescent” and “incandescent” lamps. Again, because lux meters are meant for measuring the amount of light usable by humans, they don’t tell us anything about how plants will respond.

Plant biologists define light in the 400nm to 700nm spectral region as “photosynthetically available radiation,” or PAR. The unit for measuring PAR, micro-mols per second (μmol/s), indicates how many photons in this spectral range fall on the plant each second. Inexpensive PAR meters use sensors that respond over the entire 400-700nm spectrum, and have their own sensitivity curves that require different calibration for sunlight, fluorescent and HID lighting.

All these systems are too broadly responsive to measure an LED’s narrow emission spectrum. They make HID light seem brighter by over-measuring yellow-green light, and make LED light seem dimmer by under-measuring red and blue light.
To properly measure the amount of energy present for photosynthesis we must use a spectroradiometer. This instrument measures energy in watts at each specific wavelength over a range of wavelengths. A spectroradiometer can provide a direct comparison of each lamp’s ability to produce light that plants can use for photosynthesis. Spectroradiometers are expensive instruments, not usually found outside laboratories. (A more common instrument called a spectrometer can show relative light output over a spectral range, but does not measure energy in watts.)

Manufacturers should publish spectroradiometric data showing the energy per wavelength produced by their lamps. This data will allow growers to accurately compare different lighting technologies—whether HPS vs. LED or different LED horticultural lights—and know how much usable light their plants will receive from each system.

 

[umbra]

Morning O.F.C. !--Again !-

Bud -- If U don't have the patience of an elephant this genetic doubling is not for U !-- U could have perfect technique and still never be successful !--- If your clone skills aren 't up to par then you'll fail !-- This is not a formula and if U follow it exactly U will succeed! -- This is more like fishing !

Umbra !-- Sorry about the ignorance !-- It is a medical condition and if U seized in front of me you'd be just fine !-- What causes it is a mystery! -- Others may not understand but to U got a Muse ? -- Recover from the seizure and see things different ?-- Will a strobe set of a crisis ?-- Do U have a trigger !

Yes red strobes do it for me. Certain frequency though. When I lay down and go to sleep I will feel it coming on sometimes. Not sure if it is the brain activity on overload. My son and I talked about my epilepsy for the first time after we moved to Cali. After I explain what my seizure were like, he told me that he has seen me having a seizure while was sleeping and thought I was cold. He described as my shivering for about 1 minute or so, but it was warm and clearly I was not cold. Mostly what people see is me staring off into space for 30 seconds or so. That is what they see, what I see is I loose color and peripheral vision for 15 seconds or so and then it comes back.

 

[umbra]

Single-ended (SE) high-pressure sodium (HPS) bulbs screw in like standard light bulbs, but into a slightly wider socket called a Mogul base. The glass bulb has an elongated shape that is wide enough to accommodate its inner components. Inside the bulb an opaque inner tube contains the part that creates light, called the arc tube. The arc tube connects to the base of the bulb with a metal “frame wire” holding it up by each end.

Double-ended (DE) HPS bulbs connect to the fixture on each end much like fluorescent tube bulbs. In this case, the inner, light-generating tube is supported by two small wires on each end of it, and lacks a frame wire that crosses in front of the arc tube. Without any of the metallic structure SE bulbs need to support the arc tube within the bulb, DE bulbs are significantly thinner than SE bulbs.

Exposing the arc tube to the bulb without any metal framing in the way increases light delivery to the canopy of your plants. The symmetry of DE bulbs allows you to create an even spread of light much easier than is possible with SE bulbs. Not only does the lack of wire frame improve on its light delivery and reflectance, the thinner bulb also improves its optical properties.Just going by the “life hours” listed on the packaging of the bulb or the website listing it will have you believe SE bulbs last the same or longer than DE bulbs. In reality, DE bulbs have the longest operating lives. “Life hours” for a bulb refers to simply how many hours the bulb will last before failing to turn on. Long before a bulb fails to turn on its efficiency and spectrum degrade significantly. Growers recommend changing SE bulbs every 6,000 hours, anything past that and they won’t deliver the right amount of light. DE bulbs, on the other hand, retain 90% of their efficiency after 10,000 hours of usage.

DE bulbs have a catch though. While SE bulbs are under vacuum, DE bulbs are full of nitrogen gas. The nitrogen atmosphere allows the bulb to operate at a higher temperature, which increases its efficiency. The downside of a gas-filled bulb is that the gas conducts heat from the outside of the bulb to the arc tube. Any air blowing directly on the bulb induces a temperature change in the arc tube, causing a loss in efficiency. Therefore, DE bulbs do not tolerate air blowing directly on them like in active cooling setups (aka “cool tubes” in which the SE bulb sits inside of a tube with a fan housed in the luminaire or lamp hood). Commercially available DE luminaires efficiently conduct heat up and away from the lamp; it’s the indoor grower’s job to remove that heat with either an exhaust fan near the ceiling, or an AC unit for the whole room.

 

[Keef]

Umbra it could be much worse !-- I know during brain surgery we could cause seizure with probes !--
U don't have to take phenobarbital do U ?-- I could stop those seizure myself but who wants a lobotomy !
I think within the next year or so Umbra gonna find his niche in the cannabis world !

Rose -- When I say something about my people ? -- That includes U ! -- 30,000 post and 1,500 pages -- What would be my motivation to leave MP ?--- I think at this point if I leave MP it will be because I got kicked out!

 

[Keef]

I'm amazed at how far LEDS have come since my first one !-- I know there are better lights but with the heat and power usage they are my only option !--They work O.K. but with the power savings I can grow more without using my power meter as a fan !--

 

[umbra]

With my lighting upgrade, I had 8 single ended 1Kw HPS. Now I have 4 air cooled, double ended bulbs and 2 single ended 1 Kw HPS. The air cooled hoods are unusual in that the air is drawn away above the bulb as convection allows the heat to rise above the reflective area of the hood. In this space is the air chamber. There is a glass enclosure, I would think that it serves no real purpose other than to loose about 4% due to absorption and reflection. Now, it is bright enough that protective eyewear is required.

 

[Kraven]

Yes sir, when my lights are running you have to have grow gear on eyes....not even squinting helps. I got my method 7's before I lit them the first time.

 

[Budlight]

Keef I have tons of patients and nothing but time and The drive to learn I'm glad you're letting me be a part of helping to create a zombie nation

 

[Keef]

I'm not that far advanced in the grow !-- In our house the master bedroom is in the backside of the house --
There's a bathroom and walk in closet !-- I started in the walk in closet --Then I needed a nursery/clone station so we don't use the shower much since we have another !-- Put a couple board across the tub to hold my boxes and a shower curtain rod to hold the lights !-- And I got my bloom box in another closet !-- The plan is to move out the master bedroom and into the spare room! -- Then I could use the whole back side of the house as a grow !-- Things don't always go according to a plan !-- The way it should work is I take root cuttings-- Stick them in the nursery when rooted I move them to a veg. Box -- If all goes well when it is time to harvest another group is ready !-- Right now I'm just stuffing another plant into my bloom box as soon. As I take one down !-- Oh! --If I want to do any breeding another grow space would be nice !

 

[Keef]

Umbra I got a question about light !-- It's the same sun outside from seed start to harvest !-- Make me understand why people use different lights for veg. and bloom ?-- Another thing !-- Why would someone put more light on a plant that it can use ?-- These aren 't silly questions !--I'm just puzzled !

 

[Kraven]

Due to the tilt of the earths axis spring sun has far greater blue/ purple saturation than reds and UV, as the earth tilts it changes the aspect of the refraction and the late summer / fall sun tends to have much greater saturation of the red and UV and far less of the blues /purples. As far as usable light, once again that needs to be measured in PAR values. Brightness (lumens) simply is a measurement of intensity to our eyes.....Umbra just covered the whole usable light discussion.

 

[Rosebud]

Keef, because there is no substitute for the sun.

 

[yarddog]

I can tell the sufferance in light colour. I am outside now, in the fall the light in the evenings has a yellow look to it
I have had a great day ofc. I have a chicken on the smoker and I have been drinking draft beer and smoking weed at my leasure. I saw a tractor parade today. That's how we do it down south, 50 antique and modern tractors coming down the road.
I installed my new 550 cfm phresh carbon filter today
And I found time to take a street bike out for a few hours riding. I am enjoying the last bit of summer, you can feel the weakness of the sunlight on my skin. Winter is building
Wont be long and it will be cold. I will get fat and lazy over the winter. Lol

 

[Keef]

I understand what you're saying Kraven !-- My Mars Hydro 300 Reflector Series have red blue white and I think another color !--- There's a switch on the side to turn on either Veg. or bloom or both !-- If I tune off either one I drop the light from 300 watts to 150 as it shuts off the reddish and blue chips off in veg and the other colors off in bloom with the other switch !-- 150 watts is not enough in bloom !-- I run both switches on to get the whole 300 watts from fresh cut to harvest !-- It may not be the best but I can still do this

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[oldfogey8]

very nicely explained umbra. thanks. i would really like it if grow light manufacturers would publish spectroradiometric data. i grow with wimpy t5's but there seems to be so many manufacturers with so many different degree kelvin specs. i am sure when i up my game someday and start using some real light to flower, i will be trying to figure out what is going to be the best for my plants...

 

[Kraven]

I think that a more "complete" spectrum is beneficial, running both is a plus in my book.

 

[yarddog]

I may add some light to my bloom cabinet on the winter when I can get away with more generated heat. I have those magnetic ballast, 175,250, and 400 watt. I was thinking of adding the 175 MH bulb with 4k.