Save an image with transparency?

Hi

I’m looking at different ways of rendering, and am wondering if UE4 is able to save a “render” from the camera of an object as a .png file that contains a transparent background…

so imagine a scene with nothing but a sphere and a light, I want to “render” the sphere to a .png with a transparent background.

I’ve seen the high resolution screengrab, but I’m not able to get a .png out of it? Thanks for any help!