CCD vs Film? Lots of time vs no patience? Alright, this is your place to discuss all the astrophotography what's and what's not. You can discuss about techniques, accessories, cameras, whatever....just make sure you also post some nice photos here too!
Yes, those filters are very expensive. I think optics quality also another reason. anyway, this is good for me to learn how to do Astrophotography in hard way.