Cheap LUX meter to calculate PAR and DLI

Rennpappe

Active Member
~1500 ppm of co2 will start causing headaches, dizziness, and sleepiness.
Nonsense.
It may differ from person to person but out of experience I can tell you that 1500 ppm is no problem at all. I had concentrations up to 5000 ppm and higher for hours regularly without problems.
Again, it may differ from person to person.
 
My man, you can copy / paste well.
I know all of this but as I wrote I have my own experience.
in our country every school has these co2 meters and they try to keep ppm's under 800, brain is not working full capacity over these levels and in schools its important, but yeah i have had headaches a lot before i started to ventilate my rooms and when i had visitors very often people complained about the dense air.. it depends on a human being, but anyway i also think that if you dont feel the effect of the c02 level it doesnt mean its healthy.. like there are many gases you cant smell, but if you breath that shit in - you will die.. not the best example but the air quality is importnt, i agree..
 
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Delps8

Well-Known Member
Thanks a lot! i had this (Uni -T UT383 or the Bluetooth version) device in mind after stumbling up on this y-video.. but then in his comments later he mentioned that the correct conversion rate for this device is 0.017 in case if i have also RED IR leds..any way so i will use this conversion rate and will give the SPD data to Ai so it can do what is doe best and i will compare to your PDF..

SP250 SPD is Blue(400 - 500nm): 15.4872% > Green(500 - 600nm): 43.8039% > Red(600 - 700nm): 40.7089% > Total :100% UVB(287-320nm): 0.00759645% > UVA(320-400nm): 0.140558% > Violet_Blue(400-475nm): 13.1032% > Cyan_Green(475-550nm): 17.2152% > Green_Yellow_Red(550-700nm): 65.0914% > FarRed_NearIR(700-850nm): 4.44204%

What light do you have? do you know what the model of the diodes are? Samsung or what?
I use five lights over the course of a grow, though I only use the SP 3000 if the plants are so large that they can't fit in the tent.

Looking at the numbers, 100% of the light is in the 400-700 range but I also see that 4% is >700nm. Hmm…

The numbers looks a bit blue heavy which wouldn't surprise me - a light for a 2' x 2' grow tent would tend to have more blue than normal so as to keep the plants short.

If you use 0.017 your numbers will come in high because data you've posted indicate that it's not a red heavy light. It's a white LED similar the rest of the commodity LED's that almost every mainstream manufacturer produces. The numbers for Growcraft lights are from third party testing and the 0.016 is shown in the PDF. It's a dedicated flower light with very little blue and a lot of red. Mars sells white LED so it's a much cooler spectrum with a far lower % of red.

Check the images in the PDF and you'll see how much red is in the Growcraft spectrum vs, say, the Vipar. The Vipar has so much blue, that it's got a lower conversion factor than even a white LED.

A conversion factor of 0.017 indicates an extremely high percentage of light in the red, deep red, and, perhaps, far red with much lower % of green or blue.

My Google search brings this up from this page. I have no idea if it's accurate.

A little blue (if <4%, plants may not be well formed so I'd guess it's right near that level), a shot of green so it's easier to see the plant and, therefore, easier to tend to i,t and then rock and roll in the 600-700 range because red photons are very efficient in terms of the number of photons generated for a given input power.
1710792398288.png

The spectrum shown above is very different than the spectrum the SP 250 but there's no harm in using the 0.017 factor. It will overstate PPFD so you will tend to underlight your grow. If you want to use 0.017, you can get back to a more accurate number by dropping the reported value by about 12%. Overall, using the 0.015 factor might be easier.

Yeah , Photon on Adnroid is garbage, even the S20.. phone to phone the reading differ so much.. On latest iPhones its a different story..
Yup, having control of the hardware makes life a lot easier to get accurate values.
 

Delps8

Well-Known Member
Nonsense.
It may differ from person to person but out of experience I can tell you that 1500 ppm is no problem at all. I had concentrations up to 5000 ppm and higher for hours regularly without problems.
Again, it may differ from person to person.
Submariner?
 
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