Just use 7500K halides and get the best of both lights. Halides swing to far to the left and HPS swing to far to the right. Have any of you HPS advocates looked at plant response curve charts to even see what spectri um of lights plants prefer. I thought not.
Halides provided better quality buds, better plant health and vigor as well as more resitance to insects. HPS grow often appear of to provide a higher yield but that is seldom the case. They simply aree longer stemmed with broader spaced internodes so infact they are the airy buds. If HPS growers and poor results with haildes it is simply because they bought cheap halides with the wrong K range. Nearly always HPS buds are lower potency and of lower quality and have many more insect problems as well as being more prone to nutrient deficiency problems, they have weaker stems and in general have low calcium problems.
Even this simple site's charts show that HPS is only good at providing ample lighting output in about 1/3 of the range required by pot plants. A 7500K halide is an almost perfect fit in the chart versus HPS or the cheap halide used in the example. However even the cheap halide provides good light across the full range from 400 nm to 700 nm as required for best health and growth. A halide only provides exceptional lighting in a short range of 550 nm to 650 nm amking it a good "suuplemental' lighting source at most. A halide does not work as well at any stage except an approximate two week range of budding, so it therefore if used through out the grow provides a poor quality vegative plant for budding. Therefore it is worse for use during any stage but budding. Even then it should supplement the healthy lighting not replace it.
IMHO
http://www.foothillhydroponics.com/brochure/colorhid.htm
