5.3.4 External Programs for Finding Polar Position
Many apps exist to determine the position of Polaris compared to the exact position of the
celestial North Pole. Only two of these apps are discussed in this section. However the same
concepts described here are applicable to all other existing apps.
“Polar Scope Align” is an app which runs on iOS smart devices. This program uses the device’s
internal GPS to evaluate the geographical coordinates of the observation site to calculate the
exact position of Polaris around the North Celestial Pole. It also provides some additional
information that can be useful for correct setup of the telescope.
With his application it is possible to interchange the kinds of reticles to be used for the polar
alignment, including the Skywatcher classic reticle, as well as the newer version and the
Losmandy type.
The position of Polaris is represented by a small yellow circle on a larger circular reticulum. To
effectively use this app with the older Skywatcher reticle or with the newer type, it is necessary
to take note of the hour angle where Polaris is located and rotate the Polarscope reticle to the
same angle, bringing the Polaris circle around to the correct position. You will observe that the
reticle reproduces exactly the same optical inversion caused by the Polar-scope optics.
The following figures illustrate the screenshot of the Polar Scope Align app with the classic and
new polar-scope reticles.
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Summary of Contents for EVO-ZERO
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