Opacity gradient glass

[priad]

I have a glass fully transparent exept the center wich is white, I have put a gradient ramp in the opacity slot, I have also tested in the refraction slot. This work fine exept one big thing: It kills my render time.
Why ?

[jacksc02]

are you using a bitmap or a procedural map for the refraction?
You might be better off using a blend material to make a "sticker" on the glass

[priad]

procedural gradient, humm ok I test it right now with a map.
It seems too, that when I put a opacity mask in my vraylight map the black and the white, I mean totally pure white and totally pure black in my mask map aren't well understand by Vray.