$1.99

Details

  • Released
  • Updated
  • January 31, 2012
  • January 31, 2024

Features

Sight Calc screenshot #1 for iPhone
Sight Calc screenshot #2 for iPhone
Sight Calc screenshot #3 for iPhone
Sight Calc screenshot #4 for iPhone
iphone
ipad
🖼️Get Icon
Icons↘︎

About

This app is a specialized calculator for sight reductions using the Law of Cosines method. It's designed for students learning celestial navigation and requires manual input of LHA, declination, and approximate latitude.

Law of Cosines sight reduction
Manual LHA, declination, and latitude input
Input as degrees/minutes or decimal degrees
Continuous computation of Hc, Z, and Zn
Supports North/South latitude and declination conventions
Clear and clear entry functions
Convert minutes to decimal degrees
Show original description

What's New in Sight Calc

2.0

January 31, 2024

• Simpler, more flexible user interface • Fields can be entered in any sequence • Declination entered as negative if South, positive if North • New ° key converts minutes to degrees • Minus key flips the sign of degrees fields • Approved for use in United States Power Squadrons® courses • v 2.0 is a complete rewrite in SwiftUI • Supports Dark Mode

More

User reviews

Fabulous App- Ver 2 is a much needed upgrade

Wow! What a wonderful app!
If you use the US Power Squadron SR96a sight reduction form this makes the math so easy.
Great job on the version 2 upgrade. So much easier to use and the results are perfect. Works perfectly.
Thank you. Keep up the good work.

Quick Basic Sight Reduction

You put in the LHA, plus the AP Lat or DR Lat, and the declination, and out pops azimuth, true azimuth, and Hc. Couldn’t be easier to learn and use and is a great time saver.

You can also input a meridian angle eastward instead of the LHA by inputting it as a negative LHA. I find that calculating a meridian angle eastward is more intuitive for rising bodies than LHA so this saves me the step of converting it into a LHA.

If you understand how celestial works it will also give you great circle initial course and distances just as easily. Just substitue the difference in longitude for the LHA and the Lat of your arrival for dec.

I have not yet tried using it to pre-calculate altitudes for planning sights but I’m sure it would be handy for that too.

Five stars for simple easy and very useful!
Show more

Celestial Nav Students

This app is a "must" for quick and accurate solutions to the "law of cosines"
ANEO

Sight Calc-Don't Take JN Without It !!

Slide rules and scientific calculators are not my thing. Many thanks to sight Calc for getting me through the USPS JN course!

Good for USPS Navigation and Jr Navigation Courses.

I used this a lot to get through my Jr Navigation course last year with The United States Power Squadron. It was a tremendous work saver.

Developer apps

FAQ

What is Sight Calc used for?

Sight Calc is a specialized calculator for performing sight reductions using the Law of Cosines method. It is particularly useful for students learning celestial navigation.

Does Sight Calc use Nautical Almanac data?

No, Sight Calc does not use Nautical Almanac data. Users must first compute the Local Hour Angle (LHA) and declination, and determine their approximate latitude before inputting these values.

How can I input values into Sight Calc?

You can input values as degrees and minutes (e.g., 44 degrees, 48 minutes) or as decimal degrees (e.g., 44.48833). The app prompts for LHA, Latitude, and Declination in sequence.

How does Sight Calc handle North and South hemispheres?

For Latitude, enter North as a positive number and South as a NEGATIVE number. Similarly, enter Declination as positive for North and negative for South. This is crucial for accurate azimuth (Zn) calculation.

What are the key outputs of Sight Calc?

Sight Calc continuously computes and displays Hc (altitude computed), Z (azimuth), and Zn (true bearing) as you enter your input values.

Is Sight Calc available on multiple devices?

Yes, Sight Calc is supported on both iPhone and iPad devices, making it accessible for users on Apple's mobile platforms.

How often is Sight Calc updated?

The latest version of Sight Calc is 2.0, which was last updated on January 31, 2024. This indicates a recent update, suggesting ongoing support and potential improvements.

Does Sight Calc have ads?

No, Sight Calc is ad-free. As a paid application, it does not contain advertisements, allowing for an uninterrupted user experience.