Get Black Color in transparent material?

So i want to make a cloud texture, and im using translucent material. the texture is mostly white, with black background.
and plug that to opacity channel.
and thats how i got transparency.

but, the clouds base has darker color. And when i implemented it, the bottom (that darker one) looks transparent.
so how i got the background transparent except for the specific area (both has nearly black color)?

or my method are just wrong?
here’s a simple image about what i did.


Hello Sandiodm!,

In this case, try multiplying the base color with the cloud texture, and use another cloud texture for the opacity.
Since the opacity works from pure white being visable to Black being invissible gray means transparant.
if you want black in your texture to be visible the black you will need a mask that is not identical to the one you are using now.

(You can store up to 4 masks in one texture)
How to do that? check out the first 4 minutes of this: UE4 RGB Channel/Particle Explaining - YouTube (apologies for the weird reverb)