Wed Jul 29, 2020 7:55 pm
That's because you've inputted the particles into the mask input of the merge (the blue triangle) instead of the green one, while you've merged the ellipse on top of the earth, so effectively the alpha of your steam is being used to determine how much of the (black and white) ellipse is merged on top of the planet. Change the inputs around and you should be good to go.
Sander de Regt
ShadowMaker SdR
The Netherlands