you can ask Joel Guerra about it he made this project , this is the link for his project
Práctica de render interior - Showcase - Enscape Community Forum (enscape3d.com)
Thanks for the link! I just realized, his curtain had the same texture results I get
I Think the mask texture must be only black&white, without grey..
I also tryed without grey 
can you share the mask texture ?
Sure.
I've been trying with different masks. This are two of them
This image was picture of the week by Enscape Instagram and had the same granulated texture. Does somebody know why this happen? That effect is because of the transparency after adding the mask. Probably it is wrong but how could I get the right transparent texture?
Do you use an image as mask for transparency?
Yes, I have been using an imagen as mask
Hi everyone,
I am having problems with the right texture for a fabric material. After adding the transparency, the color is turned a bit grey and the curtain stoff is granulated. How could I get the right texture for a high end rendering?
Thanks in advance
