What file format do the default Unity Gizmo's use?

This is going to seem rather finicky: I am creating my own custom Gizmo icons but when they are imported into Unity and displayed in the scene the are very pixelated:


The default Gizmo icons, like the camera and light for instance, are white with a black drop shadow. When I try to replicate the default icons, they look terrible. I’ve tried PNG-24 and TIFF formats with a variety of settings, but can’t match the quality of the ones in Unity.

I’d like to match that quality level for some potential Asset Store submissions.

Seems that switching the extension to “.tif” seems to have fixed the bulk of the quality issue. Not sure why I was using 2 t’s in the first place, but the quality is now on par with the other gizmo icons. Shadows still don’t look that great, but this is a solid start.