Hi, Bubbleblower ,

glad to find people interested.

Light measurement is the most complicated part without expensive equipment. What I do is calculate how many micromols of photons equals to a given number of lm for a given spectrum. I obtain the spectrum of LEDs used using an spectroscope, a camera and some sofware.

Having the amount of uE emitted, at least we can know the average light density in the grow. In order to obtain irradiance data, I use the same procedure than to calculate the absolute uE, so it leads to have a correction factor between uE and lux (measured with a light meter). Only problem is only works for each separated spectrum, so I need to do a measurement for each color used and then add up all them. I use a grid to build a irradiance map for a given distance from lamps.

Consuption of LEDs alone and full system is measured using a voltmeter and amperimeter.

About yields, I suggest to record as many info as possible. Both fresh and dry weight, and unprocessed yield and manicured one. I suggested to weight all the plant weigth (without roots) is fresh, later manicure and weight stems and manicure's rest (better if separately). After drying, report the bud's dry weight and stems and manicure's rest dry weight. I know its too much work weighting, but I think its necessary to eliminate the large differences induced by how each grower process its yield. With such data for each grower, at least for one time, it would be possible to normalize weight reports in a meanglifull way.

Im really interested on any suggestion on how to standarize measurements.