Light level conversion

[Rhonda Svoboda]

I am getting confused how to determine a basic light level consistancy. For example, some growers use lux. some use lumens. some use footcandles. How do I convert these into a usable guide? Also, still others use low medium high. Furthermore, there's "bright scattered", etc.
So how do I translate all this into usable information?

[Ray]

Lumens are units of light flux emitted from a light source.

Foot-candles are a measure of intensity - lumens per square foot. Lux is a similar unit, but metric - lumens per square meter.

You might find THIS ARTICLE to help a bit.

[estación seca]

Put your hand between the light source and the plant. Bright light casts a sharp shadow on the plant. Medium light casts a blurry shadow on the plant. Low light casts a very indistinct shadow on the plant. Very low light casts no shadow.

[camille1585]

To add to the excellent information already given, "bright scattered" (or bright indirect/diffused) would usually mean that the plant is placed in a spot that would normally get direct sun, but that the light is diffused either by use of a sheer curtain or some tree branches, or the plant is placed to one side of the window where it won't get the sun directly.