Translucent PNG foliage on trees

[Antioche]

Hi,
I would like to create a see through effect though the leaves of trees, essentially (unrealistically) reducing their overall opacity so that what is behind can be seen more easily (mostly when trying to show buildings behind foreground trees in archviz).
I am using trees from the VizPark collections (which are great!).
The leaves of these trees use a material with a transparent PNG texture in the diffuse channel. The opacity setting of the leaves is set to use the "Diffuse Texture Alpha" as a custom source, so that I cannot control the overall opacity of the leaves in addition to make them more see through.
What would be a good way of controlling (from within Vray) the opacity of the leaves, while preserving the PNG alpha channel already defined in the diffuse texture channel?

Thanks in advance for your help.

Cheers,

Thibaut
2hD Architecture Workshop

[ValeroStudio]

Change change the opacity map of the leaves so the leave area is mid gray.

[kenancakir]

You can use the refraction layer, with zero ior for transparency..

[Antioche]

Hi,
Kenancakir's solution (using refraction) worked best for me, as the alpha channel of the leaves in embedded in the leaf PNG diffuse texture and modifying the levels of that alpha channel would require editing the material outside of VRay to achieve the effect.
Thanks to both of you for the suggestions!

Thibaut