Quote Originally Posted by Rusty Trichome
Been called worse. Hardly original, but I guess you work with what you've got.

I'm not interrested in saving you time. But I am interrested in making you get your head in the game, and answer a simple question that you keep deflecting. Like is there a difference between Dual spectrum (commonly Dual Arc) and Full spectrum?

Since you seem to avoid research or taking your whiney ass over to a bulb retail site to see if you can distinguish between the two bulbs, I'll do some of the grunt work for ya... (or were you unable to find the answer...?)

The one I'm currently using is here:
My full spectrum bulbs.com
Inside the glass envelope is one long ceramic (or titanium for all I know) filament and support wires.
I might re-purchase, I might go with the standard rather than full next time. Depends on what's on sale. Each has it's own strength and detractors. Dual arc (dual spectrum) bulbs I avoid.

Here's an example of a Dual spectrum (dual arc) bulb:
Unnecessary and overpriced growbulb.com (sorry Dutch...it was just on the next page and easily accessed )
Inside the glass envelope is one semi-long ceramic (perhaps) filament and one MH pillow, or packet, (or whatever the heck it is) and all the support wires for both. Tiz a MH/HPS combo in one bulb.

As far as my experience takes me (around the block once or twice) the inner workings of the Full spectrum bulbs do not have the MH pillow addition, like you see in the Dual arc.
You are asking me to compare apples and oranges, and I tire of that game easily.

If this is not what you are refering to, then spell it out. I really am trying to understand what you're getting at. I'm losing my patience in the process, but that's not unusual these days.

As far as the spectrum chart goes...were my goals to have my hobby all-encompasing of time, effort and cash, and were I so anal about the minutia that I'd overlook the benefits of keeping it simple, and were I to not trust that tens of thousands (an estimate to infer actual knowledge) of indoor gardeners have had and continue to have success with a system or a piece of equipment, or a product's effectiveness, I'd keep along the same path as yours. Dewlling on something that is truly inconsequential.
We're talking about 110,000-140,000 lumens or so, (which BTW...my plants love) not a concentrated million watt laser.

If you fail to learn the benefits of doing what works for very experienced gardeners all over the world, you're doomed. And if that is the case, why do you need our validation...?

Me...? I use what works and I use it well. :jointsmile:

A couple of pictures to illustrate the two bulbs...
So a dual arc bulb is not the same thing as a "full spectrum" HPS. Who cares? You use an HPS so have become defensive stating that "full spectrum" bulbs are somehow different. I tell you now: They are not different enough from a generic HPS to matter and anything that is actually different is not actually HPS.

Anyhow, I guess it was a mistake to think that any of you cared to improve your undertanding.
thepaan Reviewed by thepaan on . Another reason to move away from HPS As it turns out, photodamage has an action spectra. It looks a lot like an HPS plus a UV light to me.... http://www.plantphysiol.org/cgi/reprint/153/3/988.pdf Rating: 5