Small Light Sources in Frame

[White Wizard]

Are there any solutions besides subpixel mapping or increasing resolution to keep small light sources from twinkling?

Say for example you have an airplane high in the sky at night. In real life no matter how far that plane is from you (reasonably) you can always see the solid light source from the wing tip. However in vray, if the light is less than a pixel wide, you'll experience the render engine missing it on some frames, causing an unrealistic twinkling effect.

Is rendering a separate self-illumination pass at upwards of 4K the only solution?

[^Lele^]

If you have sub-pixel detail, the first thing to attempt i'd say would be to raise you minimum AA rays.
A min subdivs of 4 will most surely "find" the small detail: it'll shoot 16 times within the pixel, THEN start moving towards the max AA if it found something worth shading more.
You may go to 5/6, at most, but if those do not fix it, then you're most definitely reaching the resolution limits of the pixel grid (ie. it's past the "reasonable" distance. It happens with our eyes too.), and you either render bigger (but if 16/25/36 rays per pixel didn't find a thing, good luck with that!), or simply bump the light size for those far shots, the one thing you can't do with RL planes...