Measuring LED light output

[Bigpapa]

Greetings fellow growers.

Does anyone know of a reasonably priced meter suitable for use with LED lights? Unfortunately, Nebula’s article on the subject of measuring light output states clearly that it does not apply to LED lights.

[DrPhoton]

You can reliably measure LED fixtures with white diodes, with lux meters. Monochromatic diodes such as the common blurple fixtures cannot be measured relaibly by lux meters as their spectrums fall outside the most sensitive wavelengths for photometry. As such they will under measure in comparison to other technology and just as bad, measure unreliably compared to their own technology as there is no standard for wavelengths used by manufacturers. Which makes the metric quite useless entirely for comparisons and requires quantum meters for reliable measurements and referencing.

[Weed Pharma]

Fortunately, the LED- light manufacturer's have done some of the testing for you and usually provide a guide- which if followed will keep you within the proper range.

That said: I have found those guides have your plants a little too close for optimal yields and causes an increase in plant stress and resulting grow problems.
So, learning to read your plants and adjust when needed is still important, regardless of what the meters say!

[DrPhoton]

I have seen this to be true with various manufacturers providing inconsistant recommendations and ultimately limiting the full potential of their own product. Great advice!

[DoctorJohnson]

Greetings fellow growers.

Does anyone know of a reasonably priced meter suitable for use with LED lights?

As far as I can tell, there aren't any. But a great business opportunity like that won't go unfilled for long. Look for cheapie Chinese meters that can do LEDs soon. (Hope so anyway.)

[Bigpapa]

For clarification, the reason I’m looking for a method to measure is so I can tell if the output from my LED fixtures deteriorate over time and at which point they could possibly be impacting my yields. Sure, manufacturers provide information. But how would I as a consumer know that said information is accurate. But I’m sure that the Chinese are completely reliable 🤔

[DrPhoton]

A lux meter should be fine for assesing degradation of white light sources. With monochromatic it might still be possible, as you are using the data to measure the difference of your own source. Instead of using the data for comparison and referencing of other sources. But i have never done this myself and i would expect strict rules for when taking the measurements to prevent variability. Such as the location and height parameters.

The chinese can never be trusted ^.^