Sight Reduction is a free Android app developed by Navigational Algorithms. It falls under the category of Travel & Navigation and is specifically designed for celestial navigation or astronavigation purposes.

This app serves as a calculator to determine the intercept from the assumed position of the observer (latitude, longitude), the geographical position of the celestial body observed (Dec, GHA), and its corrected altitude. It utilizes the Marcq Saint Hilaire Line of Position, intercept method (p=Ho-Hc, Zn) to provide accurate results.

With Sight Reduction, users can input the observed altitude Ho or instrumental Hs and obtain the altitude Hc and azimuth Zn using the Intercept method. The app also offers additional features such as running fixes, plotting up to 3 Marcq Saint Hilaire Lines of Position on Google maps, local hour angle (LHA) calculations, a list of navigational stars, and a logbook.

The user interface is optimized for ease of use and includes zoom buttons for map navigation, different map types (standard, terrain, and satellite), and the option to use GPS location for automatic detection.

For more information, including a manual and examples, please visit the developer's website. Sight Reduction is an essential tool for sailors, navigators, and anyone interested in celestial navigation.