Quote:

---

Quote:

---

It looks ro me like the halo is only a big problem for really bright stars. Is that the conventional thought?

---

You can see off-center reflection haloes around the two bright stars in Orion's belt in this narrowband shot:

haloes

It's not clear that they're caused by the filter, of course.

---

Hi I get exactly the same off-centre affect shooting with my modded 450D and Astronomik UHC clip in filter through my Meade 8" SN . I am still unsure what causes this.

The focus looks fairly sharp and only the bright stars with haloes have their centres skewed. If it was rotation or coma all objects would be similiarly effected and focus would be compromised and soft in final image which it isn't.