An Introduction to Apogee MQ-500 and MQ-610 PAR meters

by Craig P

An Introduction to Apogee MQ-500 and MQ-610 PAR meters


By using an Apogee Quantum Sensor, growers can accurately measure photosynthetic light intensity over any given area; making them an invaluable tool for assessing, setting, comparing and levelling grow lights.


Who are Apogee?

Apogee are market leaders in high-precision, radiation sensing technology and are utilised by professionals around the world in various horticultural settings. We at LEDGrowLights/DIYLEDUK HQ have been happily using these meters to gather grow light data for several years. As our (and other growers’) understanding of photosynthesis and LED technology has grown, so has the availability of this technology to the grower. With this, we’re excited to announce that we’re now an official Apogee stockist. To help you understand what this technology does - and why it’s so invaluable to growers - we’ve put together some more information below.


What do 'Quantum Meters' do?

These meters are able to reliably quantify for the user, the amount of usable photons that are landing on the sensor (known as PPFD (photosynthetic photon flux density) measured in micromoles per m2, per second). Dr Bruce Bugbee, President of Apogee, offers some great information about these quantum meters you can watch below.


With the MQ-500 and MQ-610 meters, users have the ability to take multiple measurements throughout their grow space, informing them of the adjustments that might need to be made to the grow light’s position or output to ensure that the desired intensity and spread is achieved. It should go without saying that by achieving optimum light uniformity and intensity over the canopy, growers can maximise the potential yield of the crop within their growing area (providing other environmental inputs are optimised). Additionally, by being able to directly relate the power draw/wattage setting of a grow light to the PPFD numbers being seen on the meter, users are able build a better picture of how their grow light is best utilised at all stages throughout the crop cycle.


Can’t I just use a LUX meter or an App on my phone?

The short answer is: not really. LUX and Lumen meters are designed and calibrated for the human eyes. This means that - like human eyes - they’re very heavily biased towards green light and configured to sense these wavelengths at a highly disproportionate level; phones are especially unreliable for this, as camera hardware and phone software varies so widely. Apogee quantum sensors on the other hand possess a specifically engineered filter that ensures all photons within the traditional PAR range are weighted equally. Additionally, the wide variance in photon recipes between different lights amplifies this dis-proportionality further. Meters that utilise precision engineered quantum sensors are much better placed to account for these differences - Apogee even provide correction factors to account for the varying grow light spectra on the market, ensuring appropriate weighting is given to each wavelength and that your meter is as accurate as possible for the light you’re trying to measure. Click the link here to view these.


To see just how unreliable LUX meters can be, check out this video by Dr Bruce Bugbee that demonstrates this.


So which Apogee is best for me?

The majority of non-specialised grow lights today emit all of their light within the traditional PAR range (400-700nm). If your light is designed to emit within this popular range (with little or no radiation below 389nm), the MQ-500 is more than good enough for your needs and is specifically engineered to measure photons within these wavelengths. If your lights emit a significant portion of their radiation in the infrared range (up to 760nm), the MQ-610 is the better choice for you. Take a look at the spectrum graph that should have been provided with your grow light - either on the box, in the manual, or alongside product photos - if the spectrum is within 400-700nm, the MQ-500 will be more than good enough to give you accurate intensity readings.


How do I best use my Apogee Quantum Meter?

 As explained previously, having access to photon density information within your grow room is useful in a number of ways. Ideally, growers should be aiming to achieve even photon-density numbers across the entirety of their growing space. In order to accurately assess the spread of your light(s) over your canopy, multiple readings should be taken over a range of positions. Additionally, the sensor head should be as level as possible with the floor/lights and free from any obstructions over the light-source. Apogee provide some accessories (sold separately) that help in this regard: Firstly the AL-100 Solar sensor levelling plate - which comes with a built-in spirit level - ensures that the sensor head is always correctly angled to take the most accurate reading possible; while secondly a choice of two wands are available, removing the chance of user obstruction and assisting the user in taking readings over those hard to reach areas of the canopy. We'll have these available to customers very soon.


Secondary Features

For those wanting to make full use of these quantum meters, it’s possible to connect them to a PC (AC-100 cable needed - sold separately) and extrapolate LOG data in excel (csv.) format.


Apogee have created a video guide explaining some of the secondary features that the MQ-500 and MQ-610 possess such as LOGGING and Daily Total/DLI functions. Take a look below.