Colouredglass -absorbtion vs falloff

i am trying to get a nice coloured glass with the colour gradation working well according to thickness.there are two methods suggested -in material guide and later materials like "blurry green glass"

i feel the older method of making absorbtion white colour and varying falloff colour and power gives correct result(Glass2).while, Glass1 colouring is uniform-doesnt vary with thickness

which is the correct method?

[notareal]

If you have no measured n-k file in use, then absorption & falloff is up to your "artistic view" of correct material. When looking these render, for me glass 2 looks better, but from render I can't say that first on is incorrect. Should look on materials if there something wrong.

I've found this old thread, very useful to understand fog panel's settings!
Now I would like to share some tips about it.
I've noticed when the Falloff multiplier is greater than 1 (most cases, I believe) the color is inverted. To prevent this you should insert the inverse of your choosen color, simply enter in the RGB values the difference to 255.

A multiplier too much high may change the hue at higher depth, as if it was causing kinda over-saturation
in this case is better using a darker color!

Great tip Tridem!

thanks Sergio, though...I'm not so sure its behavior changes for values greater than 1, I believe it works anyway with inverted color because falloff means a subtraction. Surely the color box had changed but I'm not able to reproduce the event and say what's the rule