Baader blue filter halo

[Pompey Monkey]

I'm new to LRGB imaging, but am taking advantage of the abysmal weather to play with PI on the very limited subs that I've captured so far.

What I did notice today is that I have halos around the brighter stars. Is this normal? It doesn't happen on the red, green or luminance filters:

The fact that it doesn't happen on the luminance channel suggests that it's the blue filter causing the halos. 

[happy-kat]

What telescope was used?

[Pompey Monkey]

A Skywatcher 150P-DS with the SW 0.9 coma corrector. I don't get the halos in luminance.