Why not use screw in LED bulbs instead of CFL (or a mixture at least) for a big 1200w fixture? They're cheap here in the US anyway. I get bulbs that are 15-16w, warm white or daylight spectrum, for just over a dollar a piece. .50 for the socket. Take the diffusers off and they work pretty darn good!
The screw in leds are LEDs... we want HIDs or cfl because of their light creating principles, aka sun like..
A watt is a watt is a watt
1 watt = 3.4 BTU of heat regardless of the source
A 100w LCD televison puts out the same amount of heat as a 100w HPS bulb
Yeah but the hps radiat it much more then the cfl, you can touch cfl, hps not, they work in different temps, cooling them is more efficient etc..
The piece of information you're missing is that the small HID lamps are very inefficient and small HPS lamps have terrible spectrum.
You are right, we don't want the highest output, we want to implement the ideas of led panels in HIDs and maybe not spend 2000w doing it...
And yes, spectrum in hps is reliant on intensity so it is a problem, but maybe some bulbs are better in that watt range then others who knows
Moving on; LED lights are available in a wide range of spectrum choices and that's why they're better for growing. LED lights get more efficient with more chips run softly, letting the grower lower the light fixture down closer to the canopy.
To your final point; HID lighting was an older and fully developed approach where the performance improvements had already been found and optimized. LED is just starting this curve.
Oh! And don't forget the need to regularly replace HID bulbs! AND ballasts, because they also slowly wear out.
Believe me, I tried everything, including 1000W square wave ballasts on CDM lamps. They just make a ton more heat and less light per Watt, period. There are tons of damn good reasons for the takeover of LED in horticultural lighting but if people insist on obsolete tech, no one is stopping them.
I agree, the cdm makes less light pew watt and much more heat, but people cling to their sun like spectrum... Hello ? People grew dank for years with lame hps spectrum... So what's the deal ??
Ttystikk, you are right in your approach, but I keep mentioning this because it's very important
There are 2 concepts, main strong source of light (HIDs) or many weak sources (LEDs)
That's the main difference between them, in leds you got the ability to shoot light in the same pre determined strength to any place in your canopy,
But you lost the sheer strength of a much higher rate per min main source/s
My claim is that you need a higher rate source in flowering regardless of the ppfd you already have, cuz a high rate source causes light stress, a thing science says they love best
You can’t make up for efficiency by moving the lights closer, they produce significantly less light per watt used and you still need to get enough light. So using 9 100w hid bulbs would produce exponentially less light then one “900w” hps bulb. While you would get wider spread and lowering the lights puts that output closer to the canopy the lack of output/efficiency is still there so it’s costing you more money to produce less light.
Lack of output is there yes but it's not so low to begin with, a 70k or a 100k lm in a 1x1 should be enough with that kind of spread,
And it's not costing you money because everyone knows the edges always suffer in hid grows, no matter the size of the space, in this configuration you might be able to get same results like the one plant under your center point, in all of them...