Military Grade Posted August 10 Share Posted August 10 2 hours ago, Slippy One said: PAR is spectrum sensitive isn't it? So it doesn't take into account the IR & UVB the sun omits? I believe so mate Link to comment Share on other sites More sharing options...
MindSoup Posted August 10 Author Share Posted August 10 It's a different spectrum to the light that the x0.017 is calibrated for (if that makes sense) so the reading/conversion won't be accurate. It will probably still be pretty high though, but it's a different set of rules outside, plants are seemingly a lot more adaptable/resilient outdoors. I'm too high to put my thoughts into words properly but something about naturally occuring conditiond outdoors, it might seem harsh or out of whack, but it's out of whack in a natural way that plants are used to. Link to comment Share on other sites More sharing options...
Slippy One Posted August 12 Share Posted August 12 As promised a midday PAR reading at 52° latitude, 12th August. I’m getting a whopping 1871.7 PAR!! Blimey why don’t they cook? Is it the wind? Suns full spectrum? Self watered outdoor plants are loving this intense radiation. What’s the secret here? Co2? 2 Link to comment Share on other sites More sharing options...
KC Posted August 12 Share Posted August 12 Maybe it's the Ozone layer, I can't think of any other reason, although there probably is one. I'm no Einstein 1 Link to comment Share on other sites More sharing options...
Saddam Posted August 12 Share Posted August 12 27 minutes ago, Slippy One said: I’m getting a whopping 1871.7 PAR!! How exactly have you come to that conclusion? You're using a £20 LUX meter which only measures light intensity, and the display's set to x100. That's like measuring distance with a protractor. 1 Link to comment Share on other sites More sharing options...
MindSoup Posted August 12 Author Share Posted August 12 52 minutes ago, Slippy One said: Suns full spectrum? Yes. As I explained in the comment above, that sensor is measuring all light that comes into it, not PAR. So when you use the conversion maths that appy to an LED grow light which has a totally different spectrum to the sun you get an inaccurate reading. Link to comment Share on other sites More sharing options...
Saddam Posted August 12 Share Posted August 12 (edited) The only way to accurately measure PAR/PPFD is to buy a PAR/PPFD meter and they start at about £200. If you think a cheap Chinese LUX meter with a sensor so shitty that they can be sold at a profit for £18 is 1) going to give you an accurate LUX reading and 2) you think you can convert that shitty reading to an accurate PAR reading then you're sorely mistaken. Absolutely fucking bonkers some of the misinformation posted on this site. Edited August 12 by Saddam 1 Link to comment Share on other sites More sharing options...
MindSoup Posted August 12 Author Share Posted August 12 (edited) 35 minutes ago, Saddam said: The only way to accurately measure PAR/PPFD is to buy a PAR/PPFD meter and they start at about £200. No it isn't read the thread/watch the videos . E2A and if you actually read the thread you'd see that no one is claiming it gives you perfectly accurate readings. It gives you a fairly accurate idea which for all intents and purposes is enough. Edited August 12 by MindSoup 1 Link to comment Share on other sites More sharing options...
Slippy One Posted August 12 Share Posted August 12 ~What about all that comparison testing with fancy vs cheapos? The cheapos were close enough with a lil tweaking. Have we been scammed with these £18 profit meters? I feel dirty. 1 Link to comment Share on other sites More sharing options...
MindSoup Posted August 12 Author Share Posted August 12 No Saddam has just woken up on the ring side of bed again and decided to ruin another thread apparently. 3 Link to comment Share on other sites More sharing options...
sweettooth Posted August 12 Share Posted August 12 (edited) got that same sensor, they are good 13 minutes ago, MindSoup said: No Saddam has just woken up on the ring side of bed again and decided to ruin another thread apparently. standard ++++++++++++++++++ me everytime I see a saddam reply Edited August 12 by sweettooth 1 Link to comment Share on other sites More sharing options...
Saddam Posted August 12 Share Posted August 12 The results depend entirely on what sort of light you're testing, and no conversion is going to give you a consistently accurate reading. It's a bit silly expecting the sensor of a LUX meter to do the same job as a dedicated PAR meter. LUX is just light intensity, the wavelength doesn't matter. PAR is photons within a specific wavelength (400nm-700nm) which can be absorbed via photosynthesis. PPFD measures how many PAR photons are hitting a specific area. Blame ebay for allowing these meters to be listed as PAR meters, they aren't. Link to comment Share on other sites More sharing options...
sweettooth Posted August 12 Share Posted August 12 lux can be converted to par, its why its best to use the ppfd app with this uni-t sensor and select the correct wavelength, all the calculations are done for you in the app. 1 Link to comment Share on other sites More sharing options...
MindSoup Posted August 12 Author Share Posted August 12 (edited) 1 hour ago, Saddam said: The results depend entirely on what sort of light you're testing, and no conversion is going to give you a consistently accurate reading. It's a bit silly expecting the sensor of a LUX meter to do the same job as a dedicated PAR meter. LUX is just light intensity, the wavelength doesn't matter. PAR is photons within a specific wavelength (400nm-700nm) which can be absorbed via photosynthesis. PPFD measures how many PAR photons are hitting a specific area. Blame ebay for allowing these meters to be listed as PAR meters, they aren't. Do yourself a favour and read the thread and watch the video's geez. Your making a fool out of yourself with these comments, you clearly have no idea what you're talking about or what you're shitting all over. Everything your saying has already been explained. The video gives different conversions for different spectrums, it explains that it's a ball park figure and it explains the difference between lux and par. I'm all for civil, informed debate, this isn't it..... Edited August 12 by MindSoup 1 Link to comment Share on other sites More sharing options...
McHazy Posted August 12 Share Posted August 12 Link to comment Share on other sites More sharing options...
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