iOptron SkyGuider 3550A Instruction Manual page 15

If you are using the mount without DEC Mounting Bracket, you need to remove the Camera
Mounting Block to perform the polar alignment. If you are using the mount with DEC Mounting
Bracket, you can do polar alignment with the payload.
1. Easy alignment through polar scope
Aiming through the polar scope to the Polaris (or Sigma Octantis) while adjusting the azimuth
and altitude angles until putting the Polaris at the cross hairs of the polar scope dial. Lock all the
knobs when done. The misalignment to North Pole is about 40 min (or about 1 degree in southern
hemisphere with Sigma Octantis).
2. Quick Polar Alignment
You can use iOptron's AccuAlign
polar alignment. This is achieved by making the polar axis of the mount parallel to the Earth's axis of
rotation.
As indicated in Figure 19, the Polar Scope Dial has been divided into 12 hours along the
angular direction with 10 min ticks, with a large tick every one hour. There are 2 groups, 6 concentric
circles marked from 36' to 44' and 60' to 70', respectively. The 36' to 44' concentric circles are for
polar alignment in the northern hemisphere using Polaris. While the 60' to 70' circles are for polar
alignment in the southern hemisphere using Sigma Octantis. If the dial ticks are numbered, the 12
o'clock mark should be on top (Fig. 14a). Otherwise, any one major tick on top can be assigned as 12
o'clock (Fig. 14b).
(a)
Figure 19. Polar scope dial
To maximize the benefits of the iOptron polar scope for polar alignment, you need to know
where the Polaris is in the northern hemisphere. (or Sigma Octantis in southern hemisphere.) You
may find this information via an iPhone/iPad app (iOptron Polar Scope in Apple iTune store). Shown
in Figure 20 is a screen shot of an iPhone chart. For example, on August 10, 2016, 17:50:18 in
Boston, USA (Lat N42º30'28" and Long W71º08'49"), the Polaris Position is 00hr 18.4m and Radius is
40.2min (the green dot on the chart).
TM
dark field illuminated polar scope for easy and accurate
(b)
15
Figure 20. Polar scope app on an
iPhone