When we picture the starry night, placing the camera on a tripod conventional observe that the result is not the point we see the stars but lines, whose length depends on exposure time and focal employed. We're actually recording in the photo the rotation of the earth. If the camera is pointed toward the north, all the lines revolve around a stationary point is the North Star. This kind of pictures are called circumpolar.

The result can be a very nice photos, but what if we want the stars appear as points, as we see them? The expensive solution is to use a telescope tripod with equatorial mount, or even a telescope with camera attached on it and make a move in the same direction and speed of the earth but in the opposite direction. This motorized mounts can be used to provide us a lot of work. The cheap solution is to fabricate an equatorial plane table tripod to mount on our movement to do the same manually.

The wooden planchette

Searching Google you can find much information about making a plane table with two wooden boards about 20 x 30 cm and some other things. When I considered fabricating the mine did not like these solutions for two reasons: first because the wood is very sensitive to moisture and temperature and, especially at night, it's easy to find moisture and cold. Second, because for a good night picture back away from the cities. Sometimes we find a good place near a road, but none as good as the mountain and do not see myself carrying two tables of these measures in the pack plus all the paraphernalia and mountain photography.

Other articles in this series:

1. How to make a compact equatorial plane table.
   I The problem (This post)
2. How to make a compact equatorial plane table. Facebook II Reduction of design
3. How to make a compact equatorial plane table. Facebook Machining III
4. How to make a compact equatorial plane table. Facebook IV Mounting
5. How to make a compact equatorial plane table. Facebook V Attaching the Bracket