Filters - where do they sit?

[Terrierist]

Hi All.

More advice, please. 

Where do filters sit in the light train? I'm looking to add an IDAS to suppress light pollution, I have a William Optic ZenithStar 71 with a 2" Extender to my ZWO178MC, Is it as simple as placing between the CCD and extension tube?

Thanks in advance.

Kev

[Demonperformer]

Plug it into the camera. You want the distance between the filter and the chip to be as small as possible (for minimal vignetting).

[Terrierist]

Thanks, DP, much appreciated.