GrowCNanswered grow question 4 years ago When you say "200 watts" is that the actual wattage consumed by the light or is that the advertised equivalent?
You mentioned a discrete LED emitter, not a light. If building a light from the component level pay attention when ordering the emitters. The LM301H is available in about 20 different versions with different spectra/color temperatures.
If you search YouTube for MIGROW he did a video last summer (August, September I think) on making a DIY grow light using standard household lightbulbs. He pretty much shows you what bulbs to use and how many you need. One interesting thing was the output was much better when he removed the white dome from the bulbs.