VrayMaterial reflection: Fresnel IOR VS falloff map

[pascalmarolla]

...a general question about reflection when using Vray mats:

 

What reason would you have to use a "fake fresnel" material with a falloff map in the reflection slot (with fresnel option unticked), rather than simply keeping the fresnel option of the material ticked?

I understand that falloff maps offer more control over reflection intensity in relation to the viewing angle, but I should be able to control that as well by just adjusting the IOR factor of the fresnel reflection, without the need for a falloff map, right?

[Francisco Penaloza]

IMO this come from Old trick that, we older generation, used to use when Fresnel features were not that well implemented.

People get used to work the same ways

Also there are some people that claim that if you are using single faced glass then you need to adjust the Fresnel manually with the Max falloff control. In my opinion is not necessary but, each people work a different way.

Last but not least, 'Artist control' some of us are artist too so we don't like to be trap in the 'physically correct' frame, and sometimes we think we need to go beyond those boundaries. in that case using a graph to control the Fresnel angle is way more flexible than just a number.

Different way to skin a cat I guess

[John Dollus]

because mathematical reality rarely meets the expectation of clients.

[pascalmarolla]

thanks for the replies! That makes sense indeed