how does one of these compare to a Son Agro bulb. i don't really care about temp, i just want to know what one gives off the better spectrum
This question may have been answered already, but i dont have time to search at the moment. WHAT is a hard strike? What type of outlet do these bulbs require.?
Not for digital ballasts, they require a hard strike to fire up.
There's endless advantages to these bulbs.
Got Questions? Comments? Sarcasm? Hit me with it.
This is a point I haven't seen enough discussion about to satisfy me.The only disadvantage I see over your traditional HPS or the Sun Agro is the lumen's per watt. That being said spectrum is more important to me than lumens, considering I have a 400 watt CMH in a 30x24x60 inches. Even though there is like 15,000 less lumens the color temperature more than makes up for the lumen loss.
There is a loss of lumens but.....lumans are the brightness of light that we see with our eyes. Plants don't have eyes, they don't "see" Lumens, they "see" and use SPD.This is a point I haven't seen enough discussion about to satisfy me.
At what point does the superior spectrum of the CMH outweigh its inferior "brightness" vs. an HPS? I'd like more information on that.
Thanks. I understand lumens correlate with what our eyes are most sensitive to and the limitations of that measurement for plants. That's why I said "brightness" (trying to be vague) and not specifically lumens. On SPD charts, my hang-up is they are relative, not absolute measures. They don't say anything about how much light the lamp outputs--only the spectral distribution of whatever amount they actually do output. Using an extreme example, the SPD of some 250w lamp could be much better than the one from some 400w lamp. That doesn't mean the 250w lamp will produce better results, even though it has a better SPD.There is a loss of lumens but.....lumans are the brightness of light that we see with our eyes. Plants don't have eyes, they don't "see" Lumens, they "see" and use SPD.
Another point on the loss of Lumens is the distance of the bulb from the canopy. Just like any light, the closer you are, the brighter it is. In my pics, I showed you I keep the bare bulb 5-6 inches off of the canopy. With an HPS bulb, in my set up, I would have burnt the canopy at that distance. HPS bulbs "throw heat" all the way around, while 80% of the heat from a CMH bulb comes off of the top of the bulb. I guess the question is how many lumens are you losing based on the difference in distance? I can't answer that part for you.
The fact is that by "adding" blue, even if you remained at the same lumen rating, you would be sacrificing red. Here is a post I just threw down on another thread: https://www.rollitup.org/grow-room-design-setup/74888-1550-watts-cfl-s-17.html#post979674Thanks. I understand lumens correlate with what our eyes are most sensitive to and the limitations of that measurement for plants. That's why I said "brightness" (trying to be vague) and not specifically lumens. On SPD charts, my hang-up is they are relative, not absolute measures. They don't say anything about how much light the lamp outputs--only the spectral distribution of whatever amount they actually do output. Using an extreme example, the SPD of some 250w lamp could be much better than the one from some 400w lamp. That doesn't mean the 250w lamp will produce better results, even though it has a better SPD.
I'd like to see the SPD for equal wattage CMH, HPS, MH all normalized at some wavelength. Such a comparison might use whatever wave length is most important for flowering (in an HPS comparison) and for vegging (in a MH comparison). That's not to say that other wavelengths should be discounted, but the comparison would be for the wavelength that is most critical for a particular stage of growth.
For all I know, a CMH bulb produces about as many photons in the important (for flowering) red spectrum as an HPS. But if the HPS produces a bit more, my question is: at what point does the superior SPD of a CMH overwelm the HPS's advantage in absolute output of red spectrum light.
I'm not too concerned about bulb-to-canopy distance in my particular situation since I already keep my bulb quite close.
I'm not trying to show that CMH isn't a great bulb. In fact, I'm strongly considering adding one to my current lighting for the increased spectrum. I just want to understand these lamps more. I currently veg with MH and flower with HPS (250w lumatek ballast runs either). I'm thinking of adding a second 250w light. I figure if I go with an HPS mag ballast, I'd be able to run MH + HPS, or MH + CMH, or HPS + CMH, or HPS + HPS. That'd be a lot of choices.
FWIW, even the folks I see pushing CMH bulbs the hardest (and selling them) say: "...we currently are promoting CMH over HPS as the Single Light Source, we do believe supplementing CMH with HPS is worth the effort..." To me, that says that CMH is a great all purpose lamp that can do everything well--but, HPS still packs an important wallop of light that our plants can take advantage of (presumably for packing on weight when flowering).
Peace.
Thank you.I read you're post in that other thread. Seems very well reasoned. You're point about sacrificing red for other spectrums gets to the root of my reservation about CMH. As much as I like the idea of a fuller spectrum, I'm not sure at what point sacrificing red light to get that fuller spectrum is worth it.
I wouldn't mind seeing you explain your thoughts in International Cannagraphic Magazine Forums - Ceramic Metal Halide (CMH). That thread is unmanageably long so even browsing the whole thing takes some time. Because of that I think it's fair game to jump in at any point even if you haven't read it. But the guy from Advanced Lighting (the only place I know of that's selling them) and a few others are defending these lamps strongly. Yet somehow I'm left feeling unsure what's best for me.
I don't think there is any question that the HPS will be better for flowering. Why you would run the CMH until the last 2-3 weeks is beyond me. Can you please explain that?Actually, since CMH runs on an HPS ballast, you have the option, if you like for the last 2-3 weeks running a pure HPS lamp, and running the CMH lamp for the first 8-9 weeks, then judge for yourself whether one lamp is better than the other.
Fine, so use CMH for veg and HPS for flower. I don't think MH vs. CMH is really the argument as I understand it.At the present time, with the availability of a 53$ 400w CMH lamp, I would not waste my time with any metal halide ballast at all. And if I wanted to supplement my flowering with blue, to achieve maximum potency, I would strictly supplement with CMH, since this lamp has superior maintained lumens, for example 2 x 400w hps with a 400wcmh in between. If I only had room for one lamp, it would be a tossup, but I would favour a reflectorized Gavita type 400w HPS in that scenario, for the absolute maximum in photon flux.