Answers about CFL, HPS, How Much Light...

Discussion in 'Indoor Lighting' started by Roughrider, Nov 13, 2007.

  1. Roughrider

    Roughrider Registered+

    First--28" high and you're still in veg? Wow...that's going to be a serious plant. :)

    With a plant that size you will definitely, 100% need more light, especially below the canopy. Even though the bulbs you list (which are interesting, btw) are considered spotlights, I just don't see you getting heavy canopy penetration from a 20w bulb.

    I also wonder if you're going to outgrow that area. You're going to get some stretch and bushing out. A 28" plant should grow at least 1.5 times in height in will probably double in height or more, depending on the strain. A 4' plus plant is probably going to need more than a 24" x 24" area. And I stick with the basic lumen information...if you end up using 28" x 28" (which I think you'll need for a plant that size), that's around five and half square feet. That would mean at least 10 bulbs like that; 15-16 would be a whole lot better. For cuttings, if you plan on staying in the 24" x 24" area...that's four square feet. At least 7 or 8 lights; 10-12 would be best. I'd think about having 65-75% of the lights on top, and 25-35% below the canopy as supplemental light.

    I've used CMH bulbs. 3000k is pretty normal for those types of lights. IMO, they're as good as MH for veg, but not quite as good as HPS for flowering (close, though..more than good enough). They run cool, which is nice--and you'll want to get the lights close, since they're only 20w each. You'll need plenty of lights though, as I said, so be sure and check temps and have some air circulation. Good luck!
  2. kwaaluudekid

    kwaaluudekid Registered+

    Thanks for the info, it is MUCH appreciated. I was going to start the flowering stage this weekend (they'll be 6 weeks old then). space really isn't an issue yet, they're in the garage and I use it as an office, so I'm the only one ever goes in there. right now they're just tall and lanky, but hopefully they'll bush out. I'll try to get some pics up if I can. I'm guessing these lights prolly wouldn't be too good for a trunk setup? the trunk is 13x17x31. I'm also growing in soil for now, but want to try DWC for the next grow. Any suggestions? again...thanks for your help

    (it said I uploaded pics...but they're a month old when plants were only 2 weeks old...will show more pics in "my grow")

    Attached Files:

    Last edited: Jun 8, 2010
  3. kwaaluudekid

    kwaaluudekid Registered+

    new pics with cmh grow

    here's some pics of my cmh grow. the 1st one shows height. 2nd shows whole plant. 3rd shows top of one. 4th show popcorn bud...kinda spindly, but with any luck will bush out nicely

    Attached Files:

    Last edited: Jun 9, 2010
  4. calbunn

    calbunn Registered

    have you done a grow with induction grow lights? theres some induction grow video on you tube if you've not see them and the 166.5 lumens per watt is higher then anything short of plasma without the heat.
  5. StoneMeadow

    StoneMeadow Registered+

    I have a few interesting data points for cfl and fl bulb fans. After reading some cfl grow threads where the plants suffered from burning if the bulb is too close to the plant, I decided to measure some bulb temps directly. Using a good quality surface pyrometer on stabilized bulbs (on for about an hour), I get 84 degrees F for a 34w 4100k 48" T12, and 104 F for a 14w "soft white" cfl. I guess I now understand why a T12 can be dropped right down into physical contact with the tops of the plant without causing burn, and why any cfl must be kept several inches from the nearest leaves.
    Last edited: Nov 9, 2010
  6. gypski

    gypski Registered+

    Then you'd want your T5 a distance that at the canopy was in the mid 70 degree range. Distance does matter!!!!! :pimp:
  7. jon420

    jon420 Registered+

    Dsitance and amount of light is the biggest step for growing with CFL's and floro's. I know that there are huge debates out there about using CFL's & floro's for the whole grow. Most people do great when it comes to vegging but when it comes to flowering time, a lot of people are dissapointed. Flowering with cfl's & floro's is not much different than flowering with HPS. Only difference is, the HPS penetrates further from the light source which means you don't need much side lighting, if any. A lot of people grow from above the plants only and that is where the CFL & floro growers make mistakes. CFL & floro grows should penetrate the plant from all sides if possible and as close as possible (CFL's do burn but haven't seen a floro burn yet). I have seen CFL & floro grows turn out just as good as HPS grows, if not better and of course less lumens and watts. It all depends on distance and amount.

    I have seen 467watts (34,XXX Lumens) of CFL's & floros combined to make the goodies and amounts you see in magazines, no lie, it can be done!!!
  8. headshake

    headshake Registered+

    my t-5s have burnt leaves, but only when leaves are touching them directly for prolonged periods of time.

  9. jon420

    jon420 Registered+

    Sorry, I should've specified. I have not seen a T12 burn yet, my bad. I have heard of the T5's burning and even the T8's but never a T12.

    CFL & Floro Grow Log Coming Soon!!!
    • Like Like x 1
  10. brynpav

    brynpav Registered

    keeping it simple

    Your post got me thinking about surface lamp temperatures since I've been using inda-gro 400 watt induction fluorescent lamps for the entire grow and I let the plants grow within 12" of the fixture @ week 12 with yields consistent in the 300 g/m range. I'm on my fourth grow now.

    Electrode-less induction is really fluorescent lamp on steroids emitting 166.5 VL/W, 95% PAR usable UV/IR spectra, which like an HPS gets excellent canopy penetration but still runs much cooler compared to HPS operating temps.

    With lamp surface temps having much to do with fixture design, room size and ventilation I can speak only to my particular room/lamp combination. And while I don't own a pyrometer for a lamp surface temp I don't let my plants actually touch the lamp anyway. The measurements I can give though are from readings I took with an infrared thermometer.

    I have a 90 cfm fan providing a reasonably well ventilated 10 x 10 x 8 (800 CF) grow room with an maintained ambient temperature of 78 degrees F, I measure 80 degrees F @ the nearest edge of the reflector surface approximately 1" away from the lamp itself.

    I was told by inda-gro was that these lamps actually function best, in terms of MAX lumen/watt output is that the room be ventilated to not directly remove the surface temperature of the lamp to where it falls below 70 degrees F.
  11. Indagrojeff

    Indagrojeff Registered

    hps efficiencies - not quite right

    This is my very first post on a forum, anywhere! And your having written it all has motivated me to do so. Please forgive me if I don't follow all of the protocols but I am a quick study.

    The reason I set up with this board is because one of our customers just emailed this thread to me and I thought I'd throw in with my observations as it relates to an important facet of our overall thermal management designs on the drivers which power our induction grow lamp products.

    The post you've made is well written and compares two conventional grow lamp types. However I believe there are some inaccuracies in that the values posted were for initial HPS lumens rather than mean lumens which would be a better value to use as it better reflects the output over the lamp life. I've attached a link to the chart values we like to use. In respect to the efficiency getting better as the lamp gets larger, this is true up to 600 Watts, but then the efficiency decreases as you go to 750 watts and 1000 watts. Both Metal Halide and Induction lamps continue to get more efficient as they bet bigger and do not show this backward bending affect on efficiency values as HPS does.


    My 30 year background is that of an Electrical Engineer with experience in nuclear and product development design engineering. Over the last year I've been working on the Inda-Gro design team and find this exciting, because so much of it stems from work that was brought to the industry by one of the most inspirational inventors of all time and that is Tesla himself.

    Of course I'd like to make more people aware of the advantages of utilizing induction grow light technology I'm not here to promote Inda-Gro products as the sole solution for your particular needs since there are, from what I'm learning, many reasons that would influence the lamp choice that a grower may decide to use.

    While not being a botanist by training or trade I was excited to get involved with the electrodeless induction light technology for the grower since it relies on relatively simple but delivers a high lumen/ low wattage solution for those species that demand not only proper spectrums but 1,500-1,800 micromoles saturation at the receptors to best simulate the natures energy and wavelengths.

    Please feel free to call me or call me at the office should you wish to discuss anything that warrants our followup.

    Thank you for your time, Jeff
  12. jon420

    jon420 Registered+

    The T12 3000K burns too. It took all day but it did burn. Juat wanted to throow that out there. Never had a T12 6500K burn though. Great test too!!!
  13. mickey9987

    mickey9987 Registered

  14. bushmuncher

    bushmuncher Registered

    Is it ok to hve a reptile light using a sun Glo 150w bulb It is a Neodymium spot lamp and I have two other lispot kigts reflecting off foil also.

  15. flyinhi66

    flyinhi66 Registered

    question lights?

    hey i just started 5 seedlings,they've been unger a 18watt under cabinet flu light 4 10days, ? how long should I wait to put them under a 250w mh, also would it be benefical to add a 230 watt hps conversion lamp on during veg state? been growing outdoors 4 yrs, my 1st time indoors,i purchased a 3x3x6 grow hut & have like 10 250mh & 15 175 watters. :stoned:
  16. massbud

    massbud Registered+

    what you think of my setup do you think its good or do you think it needs more light? 22.jpg 11.jpg
  17. jimbobalong

    jimbobalong Registered

    roughrider- only new to growing ventilation is ok its just the lights that have got me. I have a 250w clf for veging and a 600w hps for flowering is the 600w to much for a 2x2 grow far away should i keep the cfl from the top of seedlings??
  18. mak14317

    mak14317 Registered

    very goos posts to read..........
  19. Jungl3Jim

    Jungl3Jim Registered+

    Hey all..
    hate to drag up an old post but this has been pilfered directly from here.. albeit great info.. but still
    What Are PAR Watts? - Sunmaster is proud to publish PAR Watt information
  20. bubbels

    bubbels Registered+

    hey i use a son-t pia green power 600w and i dont know how old they are. so what can i do to measure my ligth power.? will a lux meter do.?

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