Transparency super slow

[houourin]

I noticed recently that If I was using some kind of transparency that had several layers, the render times start to grow and grow and grow.

I tried to optimize, trying "normal" instead of "stochastic", not making it "double-sided" in the settings, or "cut out " when possible... but cut out makes a hard edge so not always an option.
Isn't any other way to optimize transparency effects in Vray? it really multiply the render times x10 easily... with such a cheap effect, isn't refraction, is "just" an opacity.

Now Vray really crawls when this multi layered transparencies are in the scene.

Thank you.

[^Lele^]

Stochastic is where it's at unless you have cutouts.
No news about the performance, opacity has always been costly for raytracers (so much so we have always suggested making stuff like tree leaves geometrically accurate, rather than using opacity mapping.).
Of course, if you have noticed a worsening compared to the past, please send over the corresponding material so we can check it out.

[houourin]

Yes...
It is not worst than in the past. I'm aware for trees and other stuff, but I'm a Look Developer, and sometimes we try to push the boundaries or use stuff in a not so "conventional way"
In this case I need it for character geometric hair connection part with the head...or transparency around the eye area so hair won't feel so heavy... so we get a soft transition there... so not really an option to use cut out or use solid mesh in there...

Is it a shame not to have a cheaper option to achieve that results even if its on behalf loosing some realism. as x10 increase when using opacity is too expensive.

Thank you.