I'm considering to buy a camera such as one in the Sony NEX or Samsung NX series. Do you know which of the 2 series has a lens that is equivalent to the Sony DSC HX200V's 30x optical zoom (Focal length equiv. = 27 – 810mm)? And what is the lens's name? Thank you.
Samsung D-Xenon 18-250mm F3.5-6.3 is probably as wide as you can reasonably get for the Samsung. Similar for the NEX. 18-300mm is available with an A-mount adaptor.
BUT, on an APSC camera, if you crop a portion of the image that is 50% of the width and 50% of the height = 25% of the area you get the effect of a 2X increase in focal length.
While available sensor area is not an absolute measure of performance it is liable to be a very good indication that the APSC cameras will offer greater effective zoom ratio when using a 18mm-300mm lens than the "superzoom" does.
If you want native lenses, where you don't need an adaptor, the biggest super zoom lenses for both mounts are from 18-200mm (35mm equivalent: 27-300mm):
Sony E mount (NEX)
Samsung NX mount