The equipment I use to conduct tests if very different from what people are used to hearing about. Most people discuss using a sphere to check efficiency, a sphere is pretty old now and they were designed to test light bulbs not LED's, you may have also heard of a goniometer test, a goniometer test is done to find out how a light spreads so you can work out the beam angles, the main purpose of conducting a goniometer test is to get what is called an IES file, an IES can be opened in specific programs to view the lights as a 3 dimensional image.
Where having an IES file is useful to the people on here is because you can actually create simulation of your own grow room on your computer using a free and easy to use program called Dialux. If you have not watched this video yet is a fast explanation of how the test equipment I have works, if you watch it until the end you can see an IES file being used in a grow room simulation.
I own 2 products from Viso, one is the portable LightSpion and the other is the top of the range LabSpion