Motorized tripod heads, like the Mantona Turnaround or Movo Photo MTP-11, seem to be popular and inexpensive currently.
Can these be used as an alternative to expensive sky tracking mounts for planetary and milky way photography - yes, no, or only with nerve wrecking amounts of experimentation and calibration?
In order to track stars and the Milky Way the camera needs to rotate at the same speed the earth rotates—the sidereal rate—which is very close to 15 arcseconds / second, or 15.041 degrees per hour. This assumes the tracker is polar-aligned: mounted on a wedge angled north/south (depending on which hemisphere you're in) at an angle equal to the complement of your latitude (90° minus latitude), aimed towards the north/south celestial pole.
The Mantona Turnaround Rev.2 and Movo Photo MTP-11 appear to be the same device—likely one or both of them are white label brands. They appear to support a 15° rotation over 60 minutes, which is correct for sidereal tracking. Assuming its tracking rate is accurate, they should be able to track stars and the Milky Way.
Note that with an equatorial mount tracker, in addition to the wedge "head" under the tracker, you'll want to mount a ballhead on top of the camera so you can point the camera at the intended subject. The MTP-11 states it can support 2 kg / 4.4 lbs at an angle up to 30° above horizontal. So that spec holds for any tracking location at 60° or more latitude. They state the weight limit is 1 kg / 2.2 lbs when the device is mounted vertically, which would be the case at the equator.
I don't know how these time lapse bases are constructed internally, but at the prices listed, it's almost certain they are using plastic gears, if not also spindle shafts, etc. What I'm saying is that I doubt the weight limit specifications are grossly conservative, so keep that in mind when mounting a body, lens, and ballhead on top of one of them. Then again, by the same argument, for the price, you could afford to find out if you strip the gears due to too much weight on the time lapse base.
The first camera motorized heads (Excluding videocamera heads) were converted from astro goto mounts.
PapyWizard was a good example of automating this. It interfaced via Bluetooth or serial to a slightly modified Merlin/Orion mount. The mount was available with an 1000mm cat for about 150$. https://www.kolor.com/wiki-en/action/view/Using_Papywizard_module
Astrotrackers, however, are far more precise and use (can use) a variety of methods to help correct the motion of the tracking head. Typically the entire gear train is much more robust and contains (can contain) additional interface electronics to take a signal from an astrotracking camera.
Fun things to play with.
