And it seems to me that albedo and LRV are the same thing.
I would say this is quite correct imho, that's why I think the value of albedo/LRV/any other physical measurement can't be used directly in CGI model in some sort of hocus-focus
bro-science formula.
"Light Reflectance Value (LRV) is the total quantity of visible and useable light reflected by a surface in all directions and at all wavelengths when illuminated by a light source."
Source: http://thelandofcolor.com/lrv-light-reflectance-value-of-paint-colors/
My reasoning is you can't just multiply diffuse value (or averaged tonal value of texture) as the measured number accounted both diffuse and specular property of material, something
that is separated in material model of most renderers, like Corona. Conservatively, LRV value of 40 for example, accounts for both the tonal value in diffuse property and overal averaged reflectance from all angles combined together in one single value, so it can't be stuck for example in reflective slot alone (which is just 90 degree reflectance of specular property, and more than less should quite often be very high value, might as well leave it white ) irregardless of reflective IOR curve ( or IOR value in simplier model).
40perc. reflectance for metal and plastic while identical once averaged in LRV value have drastically different visual look, as the metal is only specular, while plastic have both specular and diffuse property while also having very different spread due to reflective curve where metal will be evenly reflective overall with close to horizontal reflective curve (with late peak at top) while plastic will have rising curve that will change diffuse into specular as it will reach grazing angle.
[[ well, actually, for some, very regular and highly reflective metals, the LRV value could probably be used directly without reaching wrong result. Since they would have almost completely horizontal reflective curve (or IOR value higher than 20 respectively ), they would reflect light already in very even fashion from all angles, have no diffuse property (super clean), so the LRV value could be then used as 0.4*255, it wouldn't be accurate, be neither look wrong, apart from layered look and simplified BRDF model
In same fashion, it could be used directly for pure-diffuse materials, but there are (almost?I don't know) none in reality, the specular property would skew the measured number
Closest match would be the regular super-matte paint wall-paint, something people now more than often learned to use properly, i.e. white matte wall being sub <200 instead of 255 commonly used almost universally before]]
Imho because of this, they are rarely useful even for eye-balling reasons as most materials are just combination of all. It's just helpful data for construction/design industry to create visual contrast in materials (often for safety reasons).
The best photorealistic freaks (in good way) can do is follow the reflectance curves under correct wavelength from table list like this :
http://refractiveindex.info/and observe materials in strictly measured photography at 0 (straight-on) angle and with close to 90degree angle.
Disclaimer : I am presenting my understanding of all this, which I only speculate on but ponder upon quite often and study for quite some time. Might not use correct terms and language,
but it's worth to look behind that, since my job is to make nice pictures, not write scientific papers.
