a step beyond T5's .....I found T4's

[Ray]

Concerning bulb lifetimes, I have read that T5 bulbs should be good for about two years, but having recently replaced a handful of fixtures whose electronic ballasts were "fried" by a power surge during the freak snowstorm a few weeks ago, I can tell you that a new bulb and a one-year-old bulb have noticeable intensity differences.

I'm going to stick with an annual replacement strategy.

[johnblagg]

very true Ray ...lol I started building some reflectors out of stainless steel flashing I have in the shop but with out a break to bend the metal it looked horrible and warped so I figured the light escaping from the top would get to the rest of the room and help out in general.

I have considered using some old shop light fixtures and fitting my set up in them

[Merlyn]

With the digital ballast I can switch between 1000, 750 or 600 watt settings and the KW meter I use clearly indicates a corresponding reduction in watts consumed.

Calbunn, your ballast settings is the same as putting in different watt light bulbs and is not a dimmer. What I said was the watts determines the cost, no matter if you dim it in half you still use the whole wattage. I have dimmers all over my house for regular lighting and I have the high tech touch dimmers and you still create heat at them when in use. Might not feel much of it but it's there. On my T5 fixture I can use 2, 4, or 6 bulbs with a switch = same thing as your digital ballast settings, and neither one is a dimmer.

[stefpix]

6500 K does not mean they are full spectrum. tehy lack red. I found a really good guide that broke down the spectrum for most common bulbs. some GE older tubes are better than the newer ones.

I have to look in my browser history or google but now I am in a hurry.

Anyway I found this - cool white usually are 6500K they appear bright to the eye and have little red / yellow but they lack some spectrum


Gardening Under Lights, Grow Lights, Grow Light, Shop Lights: Gardener's Supply
"Cool white bulbs are a good source of blue and yellow-green light, but are a poor source of red light. They are used for interior lighting in schools and office buildings, and are the most commonly available type of fluorescent bulb. Plants grown under cool white bulbs will be stocky or even slightly stunted."

[johnblagg]

well actually 6500k is the blue end of the spectrum and actually what the pot growers aim for to get the best growth rates .....red spectrum is supposed to be better for blooming .....I use a mix of both all the time cool white and warm white both.

Thats why hid lights come in metal halide and hps both, metal halide for blue and hps for the red...and if you want to spend the big bucks special bulbs with both ....

So far I have got realy good results with off the shelf generic lights of 6500k or hight wattage twist types in the warm white....lol if I could find the flat bulbs this thread started out discussing in warm white I would grab a few for sure

[Jayfar]

Originally Posted by stefpix

6500 K does not mean they are full spectrum. tehy lack red. I found a really good guide that broke down the spectrum for most common bulbs. some GE older tubes are better than the newer ones.

I have to look in my browser history or google but now I am in a hurry.

Anyway I found this - cool white usually are 6500K they appear bright to the eye and have little red / yellow but they lack some spectrum


Gardening Under Lights, Grow Lights, Grow Light, Shop Lights: Gardener's Supply
"Cool white bulbs are a good source of blue and yellow-green light, but are a poor source of red light. They are used for interior lighting in schools and office buildings, and are the most commonly available type of fluorescent bulb. Plants grown under cool white bulbs will be stocky or even slightly stunted."

There's more blue, but still plenty of red in a 6500K daylight fluorescent. Check out the java applet on Ray's site:

Light Sources & Color Temperature

First Rays' Free Info

[johnblagg]

LOL if you want to realy learn some lighting tricks and tips get on one of the pot growing forums they will have the breakdown of anything and results of leds ect .......and they go for the profit margin and least energy used for the most product so they are up on the latest new tech

[Jayfar]

Originally Posted by johnblagg

LOL if you want to realy learn some lighting tricks and tips get on one of the pot growing forums they will have the breakdown of anything and results of leds ect .......and they go for the profit margin and least energy used for the most product so they are up on the latest new tech

I know you're right about that. I wonder if there would even be a much of a grow light industry to supply the needs of orchid growers, were it not for the big demand created by our brethren in the cannabis sector.

[goes to google to look up the circulation of High Times vs. Orchids magazine]

[stefpix]

I found the page - it is a really good breakdown. After reding this I bought GE Full Spectrum T12s that had less lumens than reg T12.
Some data on commonly available fluorescent tubes

"The REP bulbs are the newest and may have been influenced by the energy crisis. They utilize rare earth phosphours, and produce more light per given quanta of energy than other tubes. Unfortunately, the spectra is kind of weird. It's very low and flat with two huge spikes, one in the yellow/red are about 620 nm and the other in the green at 550 nm. This is all but useless for growing plants, as these are primarily the two frequencies of light that are rejected by plants (they are green for a reason :-).
"

6500 K or 5000 K even if similar to daylight may not be efficient to grow plants.
and this is another good overall page.
Indoor Plant Lighting

but I am considering also something like this Amazon.com: 90w Watt UFO LED Grow Light High Power Round Grow Light Plant Light Red/blue/orange/white 70:10:5:5: Patio, Lawn & Garden

[johnblagg]

LOL the only effiecient way to grow orchids in the spectrum that is perfectly suited for them is outside ....untill then Ill stick with whatever works well enough to make them bloom well which so far I have realy not found a light that did not work pretty well for unless its a old fashion standard incadesent ...in reality the most important factor is how much power you can pump out as lumens within the range they can use somewhat towards the middle .....even a perfect spectrum will fail if there is just not enough energy in it....