I've been using Gavitas for a couple years.
@Sativied touched on this, but they are commercial. Not some hobbiest junk. I would be leery of the market flooded de bulbs and ballasts.
If your doing a small personal grow, they probably aren't for you.
- Jiji
Yes, but even then only to an extend. Lowest wattage gavita is 600w, if you got a 4x4 closet you probably grow for yield, and when yield is a factor, the gavita is quickly earned back and in practice can even be cheaper per gram (less bulb changes, professional gear that lasts longer). For growers in NL usually within a single cycle (just need one ounce more, not your ounce, our 100gram "ons" sold at roughly $500)
That's the irony of LED fans bashing and flat out lying about Gavita gear. It achieves what they pretend to be after, higher efficiency and money savings. And not talking about wall plug or electrical or luminous efficiency, but the efficiency that matters, which is gpw or more specifically g per $ electricity.
And guess what's not only the best, but only the cheapest:
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5 year is long time though...
See the umol/J (not what Supra parroted from the LED shill at icmag, when he compared to lighting materials that are currently being made in a factory...).
For large spaces with many lights the ePapillion may work better but for in a tent/closet:
And yeah yeah, you fanboys can build something more efficient with cobs that don't produce as much heat but at a quarter of the wattage need heat sinks larger than a gavita 1kwatter's ballast, and then still need fans on top of it
The irony is just hilarious and not worth more than mocking... I've seen most of you fail at having a factual discussion in probably not coincidentally another gavita DE thread nearly a year ago... Bunch of HPS hating shills that love to put up and attack straw mans.
As with most downsides of LED, fanboys go so far as to pretend they are benefits and then claim HPS is less because it doesn't have that same "feature" (read: down side).
HPS directs heat towards the canopy, unless you live in a hot dessert that's a plus, not a downside. And even then you can swap day and night. I've seen professional large side by side HPS vs LED tests in which they ended up hanging up a few HPS bulbs on the LED side to make it fair in terms of canopy temps.
And again, you can't include and then subtract the light beyond the par range from the specs...
"
The higher the PAR value per Watt, the more efficient the lamp. For this reason, Philips specifies the PAR value for all its ‘growth lamps’, expressed in micromol photons per second (µmol/s)."
Another classic, LED is more directional... no, HPS gives a better spread (unless you buy 10 light sources and run them at less intensity... lol), especially in spaces larger than a single hps bulb would cover.
The poser bullshit about BTUs... the whole heat argument is just desperate shill nonsense, with exceptions the larger growers for who that's actually relevant definitely aren't not going to tie dozens of cobs together either.
More LED-LoL: LED has longer lifetime than HPS... yeah, the chip vs the bulb... more specifically, the chip in a professional construction vs the bulb in a professional fixture.
A professional horticulture lighting setup is a much better investment.