Comparison of quantum PAR sensors

Discussion in 'Slipper Orchid Culture' started by naoki, Apr 11, 2019.

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  1. Apr 11, 2019 #1

    naoki

    naoki

    naoki

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    I happen to find this document by Apogee comparing many different quantum sensors (probably they covered all available ones):

    https://www.apogeeinstruments.com/content/Comparison-of-Eight-Quantum-Sensor-Models.pdf

    Some results are quite interesting (e.g. how Hydrofarm lied about the spectral response).

    Also, here is another comparison of Apogee, Li-Cor, and Seneye (which might be ok for reef aquarium, but not for plants):


    BRS also have 7 day rental for Apogee (MQ-510 and MQ-210). These have the calibration factors for underwater application, so to use them for plants, you need to divide the PPFD values of MQ-510 and MQ-210 by 1.32 and 1.08, respectively (info about Immersion Effect Correction Factors).
     
  2. Apr 12, 2019 #2

    TyroneGenade

    TyroneGenade

    TyroneGenade

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    Fascinating study. Horrifying revelations about the li for and apogee. All that research funding possibly wasted... Sadly, I don't expect a rush of extractions and corrigenda.

    thanks for posting.
     
  3. Apr 12, 2019 #3

    terryros

    terryros

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    Naoki, it is very tempting to rent the MQ-510 to make my measurements more accurate. Obviously, my current Apogee meter is undermeasuring PPDF because of the decreased sensitivity at both ends of the PAR spectrum. Since the MQ-510 seems to be specifically for underwater use, I think you are saying we could still use the meter/sensor and reverse the correction factor for underwater by dividing the value by 1.32?
     
  4. Apr 12, 2019 #4

    naoki

    naoki

    naoki

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    Terry, is your grow light deep-red (> 660m) dominated? If not, the error with Apogee 100 series is pretty small (about 10% or less) as shown in here).

    Yes, MQ-510 can be used. They have MQ-500 and MQ-510. They differ in the multiplier. So if you dived the value by 1.32, MQ-510 gives the same number as MQ-500. I would think they should have made a switch to change the multiplier. WIth SQ-520 (USB connection to computer), which I have, the software can change the multiplier for under water and above water.
     
  5. Apr 12, 2019 #5

    terryros

    terryros

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    My LEDs are ALT “true white” and “natural white”. Maybe it is reasonable to just conclude that the values I get from the 100 series are just low by 10-20%, depending on which end of the PAR spectrum they might favor? But, it is tempting to spend $50 for a week to verify. If I do it, I will post.
     
  6. Apr 14, 2019 at 6:16 PM #6

    coronacars

    coronacars

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    I have both the Apogee MQ-500 and the Lighting Passport. I prefer the Lighting Passport it costs a lot more, but also gives me ton of additional features. I'm selling my Apogee MQ-500 if anyone is interested.
     

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