It's a monochrome camera, of course it's greyscale. You need to incorporate filters (as DeeSkyOne said) and then stack each filter separately before combining them in post processing in order to get a color image. If you want a simpler method then you need to get the ASI2600mc Air which is a color camara and produces color images. You'll still get greyscale images with the MC version, but if you debayer the images before stacking they'll apply the bayer array for the pixels and the stacked image will be in color.
