Wow, nice to see this thread grew roots.
I moved onto a manufactured led light (now trying to figure how to cool it quietly), but a few pieces of info to add for the strips and diy...
5050 flex strips do come in 120led/m, and they can compare similarly to the rigid 5630 72led/m strips
in terms of watts(lumens) per distance... depending on the exact resistors used on each.
That is one issue - many of the strips (or any led light) are assembled to run at lower than their maximum wattage, and different makers use different resistors so the actual wattage varies. (And some of the sellers list conflicting specs on the wattage and other specs).
Factors affecting the actual wattage of a led strip
-afai have seen, the flex strips and rigid strips seem to use the same 'wire' thickness for the circuit. so that factor is maybe always the same for all strips.
-the resistor used, can be different. What matters is the ohms of the resistor. The lower the ohm rating (resistance), the more wattage will go thru/ more wattage be actually used. Each resistor has a code printed on it, and there are online code translators to translate it into ohms. Lower ohms = more wattage used = more lumens.
(-and of course, combining the circuit itself, with the wattage loss due to distance of the run. .5m is best. For 1m lengths, double-feed or center-feed, if possible.. to get the same wattage as using .5m lengths )
1m length
(+-)
----------(+-) (double feed)
or
-----(+-)
----- (center feed)
gives the same watts per distance as
.5m length
(+-)
----- (end fed)
The only way to know the actual wattage is by reviews that measured the wattage on a specific item (using kill-a-watt, etc), or to get the resistor code (ohms) on the strip and calculate the wattage (and keep in mind the wattage loss over distance), or get a strip and measure it.
Benefits of leds over cfl..
all of the watts (lumens) of
leds are focused at plant-efficient color wavelengths. a cfl provides a wider range of wavelengths, compared to a more focused range from LEDs.
a 6500 blue or 2700 red from a cfl is a broad spectrum of colors,, not the same pure blue or red that an led can give.
(though cfl will give a wider spectrum... though though a few grows posted have already shown that usual blue strips and red strips can grow healthy plants the whole way. (veg seems to be easy, even with only cool white or warm white. flowering seems to require making sure there is 'enough' red.)
Plus, with leds, they can use lenses, to put 93% of the lumens right where they are pointed, in a 5 degrees, 10, 15, 30, 45, 60, 90, 120 degree angle. Just attach whatever angle lens will extend to the width of the plant canopy, and no light will be lost by sideways dispersal... similar to a laser-pointer With cfls, a reflector guides the light, but after it is past the reflector, the light can disperse ouwards.
Even with lenses, reflective walls still are helpful to capture the light that bounces off the plant, and reflect it back.
Some strips have no lens and spread the light at 180 degrees... helpful when the distance to plant is zero, but will cause a lot of lost lumens(watts) when the plants are any distance away.
To use led lenses, they can be thought of as creating spotlights of a color. Make sure the spotlights of different colors are overlapped, so all parts of the plant will receive all colors.
.. a 60 degree lens, will create a spotlight of 7" diameter, at a distance of 6". The farther the lens is from the plants, the wider the diameter will be.
(measuring 90 degree and 45 degree angles is easy using paper or anything with a right angle. Otherwise a protractor makes any other angles easy to measure.)
1. First figure the minimum distance the plants may get to the lights.
2. Look at the led array, and figure what angles are needed, so that all of the plant canopy/grow area (*at the minimum distance), will receive all the led colors. (If an led array has a lot of red and blue, and only a little white.. the white leds may need a wider lens than the blue and red leds, since each white led will have to cover more area.)
3. Once those angles are known, that's it. They will adequately provide all colors to the entire grow space, at the minimum distance. Any further distance away, some of the 'spotlights' will shine larger than the grow area.. but there will be much less light leaving the grow area than there was with no lens. (and reflective walls can recapture any escaped light).
Don't fret with finding the perfect angle. The goal is just to direct much more of the light directly to the grow area.. unless you enjoy being precise
You just want to cover the entire grow area, and 'save' alot of lumens from being lost.
Within a cabinet with reflective walls, lumens being lost is less of an issue... but each bounce off the walls does lose 10% of the lumens (90% reflectivity), so why using lenses can still be advantageous.
Lenses can be as little as 25 cents each or so.