MQ-610, You Just Don't Know Until You Know

Right off the top I have to wonder why I waited so darn long to get a Apogee PAR meter of any model or type. It cost less than a good middle of the range pistol and not much more than a set of good motorcycle tires in this current dumbo market. Like many others I guessed for years and used LUX, Foot, Candle and other meters. Every so often I would luck into getting my hands on a high end PAR meter or a focused radiation array meter or other claimed high end light meter and take all sorts of measurements and then use all the conversion math to make something out of LUX meters or other devices. Some of these other meters were really high end and insanely expensive. Some as much as 10x the current cost of the meter I bought this week and very hard to use. Honestly I always found the data suspect. So as recent as two or three weeks ago I went ahead and installed Photone on my iPhone 13 Pro Max and paid for the Pro version, made up a diffusor sleeve and went to measuring PPFD, DLI and checking the spectrum of my HLG 100 V2’s at 4000K that I’m vegging with right now. I knew right away I was getting readings that were way way to high and thus not useable. I was getting readings of 500 to over 600 PPFD on the light type being set on LED Full Spectrum, Sun Shine and LED Blue White was higher still yet. I figured since the 100 V2’s were 4000K LED Blue White would be the setting needed. Nope!!! I knew one of my neighbors has some cheap PAR meters and I would wait for him to get back from vacation and borrow what I needed to get a calibration on the app/iPhone. Then the stinking thinking kicked in, joint and some booze and we are now in research gear to get a Apogee meter and stop with all this needless BS. My first question was how often do these things need to be calibrated? Apogee suggest recalibration every two years and currently cost $50 plus shipping both ways. In consumer hobbyest use with out the unit being left in a car to bake in the summer or freeze in the winter or tumbling down the side of a mountain. I would think 3 to 5 years would be more appropriate for calibration. Then they mentioned to use the Clear Sky Calculator to check your Apogee meter to make sure it’s in good working order. Then I said four letter words to myself and aloud. I could have used that Clear Sky Calculator to get a calibration on the Photone App, more four letter words. I think the Clear Sky Calculator in accurate to +/- 4% world wide. And yes there’s more four letter words spewing from my simple mind and big mouth. So the decision had to be made, do I go with the MQ-500 Full Spectrum or the MQ-610 ePAR (extended spectrum)? With me being me I had to also look into the new DLI-500 and DLI-600. And there are also the Quantum Sensors that have a USB-A connector that you plug into a laptop or desktop computer or one of there Microcache units. The DLI-500/600 looked intresting. But I knew I wouldn’t be able to see the real time readout on the led screen under the lights, so they ultimately got blown off. But would be very good for nursery and field work which they are clearly more geared for. So we are back to the MQ-500/610. The 500 is a 400 to 700 nm par meter. The 610 is a 400 to 750 epar meter. It’s job is to extend it’s ability to read the far right reds above 700 nm. So if your going to play in the new brave world of extended red range your going to need it. But I’m going back to UV. I use to run UV alot in the old days. Had a small fortune tied up in florescent UV and other light sources. It’s for real and I enjoyed using UV back then. So in my current lighting systems I have bought a HLG UVA-30 for my 3x3 tent. And have a UVA-30 XL for the incoming 2x4 tent to pair with a 350R. The MQ-500 has a Spectral Range of 389 to 692 nm while the MQ-610 has a Spectral Range of 383 to 757 nm. From testing I’ve seen and read about the MQ-500 does not see/calculate any UV into the Par/PPFD number. But there is testing on the web that shows the MQ-610 does see some UVA and it calculates into the PAR/PPFD number which can be clearly seen buy turning on and off the UV fixture and watching the PPFD number change. So not only does the 610 offer some future proofing as grow lights go above 700nm in the far right, it see’s UVA to a degree. I received my MQ-610 today, put the battery in and went straight to the tent. After seeing how much lower the 610 was reading than my Photone App. I then went and checked them both with the sun and then used the Clear Sky Calculator to check the 610 and phone app. Photone is still way off. Came back in and calibrated the Photone app to the MQ-610 and all the sudden they were within 15 PPFD instead of 200+ PPFD of each other. And that was a really down and dirty fast calibration. If I put a stool in front of the tent and stabilize myself I’m sure I could tighten up the calibration even more. I can’t state enough how glad I am that I now have this meter. Yeah they aren’t cheap. But most things worthwhile aren’t cheap. It’s really rare when the cheap item stacks up well against a top tier product. And in the weed game it honestly never happens. If you have the grip you know what to do.


Well. Now I am really confused. I didn’t know i had to calibrate the photone. Do I?

No. What he is using is a dedicated PPFD meter. Your phone is only capable of seeing light wavelengths visible to the human eye. A PPFD meter sees all of the wavelengths of light that the plant itself sees.

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Thanks again @MidwestGuy .

Photone does not work worth a fud on my iPhone Pro Max. I had it calibrated yesterday. And today it was out 100 PPFD. I’m working with the support division. But it looks like there gearing up to blame the diffuser paper, my phone or the meter. I paid for the Pro version so I’m going to work them a bit… LOLOLOL. The Apogee meter is expensive and the best common/research/working meter on the market. And I’m glad I have it.

Hey, I am interested in a PPFD or any reliable way to measure my grow lights. The Apogee brand is just over my budget, but I’m sure they work great. There are so many light meters available on Amazon! I don’t need a research-grade instrument, just something for LEDs that I can trust. Any suggestions would be really appreciated!

There’s a phone app out there called Photone.

Thanks, MidwestGuy. I got the app and have now learned that I need much more light than I am using!

   MidwestGuy   Bergman's Lab   

April 25


There’s a phone app out there called Photone.

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Recommend minimum PPFD levels by growth stage:

Seedling 300 ppfd
Veg 600 ppfd
Flower 800 ppfd