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Are all HPS lights about the same color spectrum?

Discussion in 'Grow Room Design & Setup' started by VirginHarvester, Jul 19, 2008.


    VirginHarvester Well-Known Member

    Trying to learn all I can about lighting right now.

    Have been looking over HTG supply and had a question about bulb quality and spectrum of the major brands.
    High Tech Garden Supply

    How important are the "sub" colors like violet, yellow and orange?

    Would any good HPS have a complete balance of all the spectrums or are some inherently more complete and balanced than others. I wouldn't want to get a bulb that is just "red". All the big HPS brag about their quality for flowering but they don't say much about the overall characteristics of the light their bulbs produce other than "it's a fantastic light for flowering" and only mention "red".

    Also, some of the HPS bulbs boast an increase of x percent white spectrum over other bulbs which seems to mean they would do a good job of vegging also.
    To put it another way, I'm getting very good vegging off six 26w CFLs for two plants so a 600w HPS(90,000+ lumen) with at least some white spectrum seems like it would do at least as well and wouldn't require an MH bulb for vegging?

    Are the hybrid/dual arc bulbs that combine an MH and HPS in one unit a good idea? And, if a real good HPS also has a significant or adequate amount of white to veg would a dual arc be cool and great but unnecessary?


    ceestyle Well-Known Member

    Read the GROWFAQ section on lighting and maybe a thread or two in my sig. You have asked some big big questions. Some have long answers (GROWFAQ), and some are out for debate.

    My short answer is that vegging with MH and flowering with HPS is the best proven option. If you are only going to have one room that you will switch from veg to flower, you might go with an HPS ballast and CMH bulb for veg that you switch to HPS for flower, but you can also use a fuller-spectrum HPS bulb (you quoted a typical claim for a bulb of this type) all the way through without problem.

    Ideally you'd have a veg room runing a true MH bulb with MH ballast, and a flower room with HPS bulb(s) and ballast. YOu can continue to have a veg room with your CFLs, buy an HPS and build a flowering room with that. You can then upgrade your CFLs to MH later if you so desire.

    Oneton Well-Known Member

    you can use hps all the way, thats what i usd to do quite successfully
    first time with a mh cant wait to see the diff

    espskillz Active Member

    don't mean to hijack but i would too like to know the difference between brand name bulbs and cheap ones i am about to but a bulb for my new set up and i want to know if its worth it to but a 80 dollar 600w on ebay or a 40 dollar 600w ebay.

    ceestyle Well-Known Member

    They all list their lumen output. You can judge by that whether it's worth it in terms of power.

    In terms of spectrum, if they do not specify that they are "full spectrum" or some other such adjective, they pretty much look like the one on the right here. Compare to the super HPS here, and you can see the basic difference. A bit more blue. I can't tell you for sure whether it's worth it, but I would probably pay for it if I had money to burn.

    VirginHarvester Well-Known Member

    ceestyle, it looks like the Hortilux "blue" MH is a great light for all stages of growth. It's lower in "red" than the Super HPS but does the plant really care... or would the plant be happier(big, stronger buds) having a much more balanced total saturation than getting the peak "red" from the super HPS but not much of the other colors? It seems to me the Hortilux blue is superior, unless that's just not enough "red" to get the job done. My understanding was most people switch to HPS as soon as sex shows but with that balanced spectrum MH blue I would think you could go all the way or maybe the last three or four weeks with the Super HPS. Best case scenario seems like a 400W blue and a 400W Super HPS in the same reflector but I guess there's no such thing as a dual ballast?

    That's a really nice link.
    Last edited: Jul 19, 2008

    ceestyle Well-Known Member

    The thing that you can't tell from those spectra is that by adding blue, you are taking away red, if they have the same lumen output (I think the blue bulb actually has lower lumen output). Red has been proven the most important spectral range for large, tight buds.

    espskillz Active Member

    all of you have been very helpful i just purchased a 600w
    Super HPS Deluxe from htg supply for 75bucks!

    [email protected] New Member

    Actually they do, i forget whats it's called but it has a 400 mh and a 600 hps in. 1 ballast 1 reflector 2 seperate cordsets, sockets and bulbs.

    stucklikechuck Well-Known Member

    the super blue

    EYE Hortilux SUPER BLUE

    or you can get a digital ballast and run mh and hps under one hood...

    owixomen Active Member

    i dont know man i just like the tried and true veg MH. and flower Hps. BUT!!!!! I would like to some time try adding a 400w Mh and a 600W Hps in a 1K w flowering room............................? wait that sounds like a great idea i might do that

    ~ smokes up~

    VirginHarvester Well-Known Member

    With two bulbs, one ballast, can they be run independently so you're only vegging with the "blue" bulb? I take it with a dual arc bulb both burn at the same time regardless of the ballast.

    If you have a 400w 32,000 lumen bulb that has 50% relative energy in the blue spectrum vs 110,000 lumen with 20-25% in the blue, the 110k seems to give about 30% more blue energy overall, which is nice. But I should expect the 110k to deliver that at 3 times the power usage(110/32), right?

    Grow room size is another consideration so how do you balance that, or how many lumens is enough to get great results in a 42"x42" space?


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