Does the plant really care what type bulb it is getting the light from?...eg. 20,000 lumens at 6500k....if the plat receives it from t5 or metal halide does it really matter? The t5 will be cooler and more spread out, hid will be hotter and more nfl. but is the most important thing to the plant lumens and kelvins (6400 blue vs 2700 red)...aside from the color is the amount of lumens the most important thing to the plants needs?
YES the plant cares it MATTERS ... IF your using cfl like I am you for optimal veg you want 6500k for optimal flowering you want 2700k .. Trust me just read up on it in the forums . that is one thing most people will agree on ..
i did mention the different spectrums in kelvins...blue-veg-65ook, red-bloom-2700k....the question is based on the actual "lummens" or brightness of the various spectrums you are providing...whether it be t5 or hid, if you are wanting to veg and use 6500k, does it matter which type of bulb if the lumens are the same.eg. 30,000 lumens....i know the cost per watt, and the heat sig,. will differ, but does the plant care what kind of bulb...as long as the proper spectrum and lumens are the same
But the lumens wont be the same. Lumens are not really cummulative. As you said, a bunch of t5s spreads the light out over a larger area. Take for example a 600w hps. It should put out right at 90k lumens. Comparatively a 54w 4ft t5ho will put out about 5k per bulb. So 18 of those would "equal" a 600hps. It really doesn't though because all you have done is spread 5k lumens over a large area and at no point in the grow area are you going to see 90k lumens under the t5. Larger bulbs with higher output will give larger yields.
remember lux to which is the intensity on light and hps lux is much stronger than t5 but you get good veg with t5
