With my RASA I always get some form of halo no matter which filter I use, this is due to SCT design and cannot be avoided. Different optical systems will yield different results. I get halos with my IDAS LP filter when used with CMOS OSC , and I can show some examples of halos on L-Enhance and L-Extreme. I used to have Chromas in my previous setup, and even those can suffer halos too. See the linked thread for the issues I read on Chromas. So for me it's performance at a price point that doesn’t kill the bank. I’ll be posting some test images from the high speed UNB’s once it gets a bit darker here and clear.