Particles sized to screen, not scene?

Using 3.0f5.

I have these particle systems, billboard aligned, and it seems that, no matter how close or far the camera is, the on-screen size is the same. Thus when I'm far away, it looks like a giant cloud, but in near, it's tiny compared to the object the emitter is near.

Is this expected? I don't see any 'scale to screen' implying settings. I need them to scale properly (that is, not to the screen, but to the scene)

Set the max particle size to something larger than the default .25. Keep in mind that huge particles can cause fill-rate issues, which is why that setting exists.