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Do you measure PAR for your grows ?

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    Greetings all, someone posted a good link about a app called Lux for your phone that you can use to tell how much your lights are putting off. That seemed pretty usefully to me. Just found out last run my SP2000 was hitting 60k-80k lux at some spots in my tent at 8-10 inches away from the top colas and colas weren't even bleached yet. Goes to show you just a phone app can help you out some. I was having my leafs turn yellow so fast even me tripling my cal/mag wasn't even helping which normally does the trick. The thread which I saw the lux app said you only need 30-40k max which is what the sun does on the brightest day outside. Happy growing all.
    Ace's Killer A5 - International Cannagraphic Magazine Forums"


      The sun at noon on a clear day will produce as much as 130,000 lux or 2000 PPFD and wont cause light bleaching due to the high ratio of blue light (approximately 1:1) but very likely is surpassing the photosaturation threshold of the upper chloroplasts. The lighting thread in my signature has charts showing DLI outdoors from full spectrum sunlight in the San Francisco bay area from March through August, more than 60DLI accumlated somedays. Bruce Bugbee mentioned in his lighting myths video cannabis can utilize more than 43.2 DLI typically regarded as most productive but spectral ratios have major influence on plant utilization. (I cant wait to experiment more with 14 hour on 10 hour off flowering by utilizing 730nm at lights off for increased DLI under different lighting types/spectrums).

      500 ppfd under 3500k led with minimal IR is roughly 30k lux and with adequate overhead diffusion to reach deeper into the canopy (or additional side lighting/under canopy lighting to stimulate lower leaf chloroplasts) people have claimed 2gpw. This is also approaching the "theoretical" max ppfd plants can tolerate at atmospheric ~400ppm CO2 availability.

      An HLG 600 rspec hung 36" over a 5x5 space will spread 500 ppfd to each corner and close to 775 ppd in the direct center below the fixture.
      Originally posted by AVOH
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      Guy, I have been testing coco for years, right out of the bag. It's all salty.

      Suggest you drop the blind faith and use a bit of science.
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      Originally posted by Ibechillin
      Diffused light > Spectrum.
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        Greetings Ibechillin, I can claim to hit 3 lbs with just 400 watts of light myself. Happy growing .
        Ace's Killer A5 - International Cannagraphic Magazine Forums"


          From the apogee website. You have a 500 (old), they now sell 520s.

          I like the USB version so I can use their logger SW and display on a flat screen. I ideally would have one in each tent, mounted on a cross-brace I cn adjust the height on, so I can set the lights from the control closet without having to go in and out of the tent.

          That 500 will work just fine to measure the power output at the height you have the lights. Co-relate the plant response to the light number, for YOUR lights in YOUR tent. At least you have a meter, cause without it I have no idea what the plants are getting.

          You missed this chart. You bought a ebay 500 (black line):

          I am using this right now, and am about to get another.

          Originally posted by stickyunderwear View Post
          I kind of was scratching my head over this and I went back to look. Especially since this was an upgrade for an older version for me.

          I compared the 500 to your supposed better 520. Dude they use the exact same sensor and the specs are the same. The 500 IS a full spectrum. The only diff is one is plugged in via USB to a laptop or desktop and the 500 is self contained. The difference is a correction factor for using UNDER WATER I dont know about you but I dont grow plants underwater.

          From the Apogee website.

          Apogee quantum sensor are calibrated to make absolute PPFD measurements in air. The waterproof sensors can be used to make absolute PPFD measurements underwater by applying an immersion effect correction factor, the SQ-420, SQ-520, MQ-210, and MQ-510 already apply the correction factor. For details on making underwater measurements, please refer to Underwater PAR Measurements.
          Kind of puts a dent any any words from you. Sorry.
          Last edited by flylowgethigh; 02-19-2021, 15:40.
          ______________________________ __________________________
          Dr. Tuggle's Compound Syrup of Globe Flower


            Originally posted by stickyunderwear View Post
            I kind of was scratching my head over this and I went back to look. Especially since this was an upgrade for an older version for me. snip...

            Kind of puts a dent any any words from you. Sorry.

            Really? I care not what your opinion of what I post up is. I am new at this felonious bidness of growing dope, and posting ideas as I find them. Hint, in a past life I made my living being technically competent. I am approaching growing like any other technical problem.
            ______________________________ __________________________
            Dr. Tuggle's Compound Syrup of Globe Flower




              DUDE look at the specs to compare. Use the compare function on the Apogee website in the products section.THEY ARE THE SAME EXACT SENSOR. Just used differently. The 500 series uses the EXACT SAME SENSOR across the board for all. Not sure why you think where I bought it matters, its a genuine Apogee including the serial number, the wand even the original box etc. They dont sell a secondary type line so your pulling the ebay thing out of your ass is a laugh. People buy new ones from Apogee and if they are done with it put it up on ebay, thats what I did with the MQ 200 I bought a couple years ago. And at some point this year I will sell this one and upgrade to a P2-141 Far Par unit since I already run additional red and far red LEDs mounted on heat sinks integrated with my main light.
              I know you feel like the smartest guy in the room but sorry. Over 4K posts in less than a year and a half, thats diarrhea of the mouth and your my first ignore since I have been back. Good luck and try reading more instead of talking.