Setting up an equatorial mount with a level

Some people experience difficulties with handling an equatorial mount. However this method is based upon the same principle as the 'two star alignment' of many Goto mounts, using the zenith as one alignment 'star' and another object (can be even the Sun) as alignment stars. This method describes setting up with a simple level mounted on an angled hook which equals the local latitude. I have made an adjustable hook from aluminum strips but you van also make such a level from a piece of wood with two flat (straight) sides which exactly intersect with an angle equal to the local latitude. The benefit of this method is:

• Tripod exactly level is not required
• In areas where the Pole Star is not visible, such as the tropics where it is too low or when you are in the south, the pole star is only the 5th magnitude star σ Octantis. But also when Polaris is hidden by a wall, mountain, etc from your observing location, e.g a south facing balcony.
• This procedure can be performed in daylight as well even with only the Sun in the sky (but more bright objects such as the Moon or Venus align better and using the Sun requires eye safety precautions). Refer to the yellow box text on this page.

It requires that you know the local sidereal time, latitude and positions of one or two alignment objects.These can be found here where you must fill in your coordinates and timezone once. If you want to use it without sitting at the computer, this script can also be downloaded as a zip file, to a PDA or smartphone with a javascript enabled browser.Then it does not require a further internet connection on the device. To do this, unzip the zip archive and upload the files to the device (or upload the zip archive to the device and unpack it there if possible).
During night you need a red flashlight, the best is a headlight as you have your hands free.

The adjustable level hook made from Aluminum strips and a level bought in the local hardware shop.

The procedure I describe here is for a Vixen Super Polaris mount, but most, particulary transportable EQ mounts work similar.

1 Set up the tripod and tighten the tripod screws firmly. It is not necessary to set the tripod exactly level, only roughly level suffices. As long as the RA axis points to the celestal pole as accurate as possible, then the mount is adjusted. The polar axis should be pointed as closely to true north (or south in the southern hemisphere) as possible. Have ready the positions of two bright objects. In the daytime this can be the Sun (and Moon or Venus if possible). Note the local sidereal time changes by time (23:56 hours a day which means during the 5-10 minutes of alignment one minute for each minute of time).!! Use a low power eyepiece with a true FOV of at least 1 degree, for a 10 cm 25-40x is OK.
When the Sun is involved for alignment, have a cardboard aperture of 5 cm ready to stop off the objective to prevent overheating the star diagonal or eyepiece.

2 Now point the telescope to the point where you think the pole is. This means parallel to the polar axis and on top of the polar axis (zero hour angle). Now set the level with the angled hook on the telescope tube and adjust the latitude screw (fig 1) until the scope is level (fig 2). Lock the declination axis.

3 Rotate the scope 90 degrees left on the RA axis. Check the level again and adjust with the declination fine control. Rotate the scope 90 degrees to the other side (this means 180° relative to its current position). Repeat step [2] if necessary. 4 Now the scope should point at the altitude of the pole. Adjust the declination circle so the declination setting circle is exactly 90 degrees (fig 4). 5 Point the scope to the zenith and check with a level in two directions along the tube or with a bidirectional level on top of the scope so the scope is exactly pointed vertically (fig 5). The declination circle should now read the same number as your latitude. If this is not the case, repeat from step [1]. 6 Adjust the RA setting circle to the current local sidereal time (fig 6). Now point the telescope to the position of the first bright object according to the setting circles.
NOTE: Some mounts, like mine, are equipped with northern hemisphere only RA circles. In this case, when you are in the south subtract the RA from 24 which means 16:29 reads 07:31 on your 'northern' circles. 7 Adjust the horizontal azimuth until the bright object is in the scope field. When the azimuth is far (> 10 degrees) off the real azimuth of the pole which means the polar axis azimuth is not true north/south) check the polar axis altitude as described in step [2] when the tripod is not level. And then go to step [5]. Otherwise, continue.

8 When this is the Sun, refer to the yellow box text on this page for safety precautions and DO NOT LOOK THROUGH THE EYEPIECE!!. You can check whether the Sun is centered by checking the exit pupil image centered on the eyepiece as shown in the image right.
When another object watch through the eyepiece and the object will come into the field. If not you have made an adjustment error of used the wrong coordinates. Maybe the object can have moved westward since you performed step [4], 1 degree per 4 minutes. When you see the object you are ready. You can check with another object at least 60 degrees from the first one and when you see that one also: Congratulations.

For further adjusting (e.g. long exposure astrophotography) you can use the drift method