Sight Calc vs Aqua Map Boating

Sight Calc is a specialized calculator for calculating sight reductions via the "Law of Cosines" method. It does not use Nautical Almanac data, so you must first compute LHA (Local Hour Angle) and declination, and determine your approximate latitude. It is designed particularly for students learning celestial navigation, such as the Celestial Navigation courses taught by the United States Power Squadrons®. If you are unfamiliar with how to do sight reductions, some good resources are available from the United States Power Squadrons® at www.usps.org. In particular, this calculator is useful in conjunction with Form SR96a, www.usps.org/eddept/n/files/sr96a.pdf Inputs may be entered as two numbers: Degrees - left column Minutes - right column Or enter as decimal degrees (e.g., 44.48833). Sight Calc will prompt you to enter six number in sequence: LHA (degrees) LHA (minutes) Lat (degrees) Lat (minutes) Dec (degrees) Dec (minutes) In v 2.0 you may enter values in any sequence. Hc, Z and Zn are continuously computed and displayed. Be sure to enter North Latitude as a positive number and South Latitude as a NEGATIVE number. Sight Calc will take the absolute value of Latitude in the law of cosines formula, but needs the hemisphere to calculate azimuth (Zn). Similarly, enter Declination as positive if North and negative if South. (Note: this differs from version 1.x of Sight Calc.) If you want to do repeated calculations with some of the same numbers, just enter the changed numbers. To start over fresh at any time, press "C" to clear everything. "CE" key clears the Current Entry. Optionally, use the "o" key to convert minutes to decimal degrees, add that to the degrees field, and clear the minutes field. This has no effect on the calculation. Please report any bugs or suggestions to: sightcalc@nuvocom.com

Free 14-day trial for all subscriptions   Aqua Map offers weekly updated OFFICIAL NAUTICAL CHARTS (NOAA) for marine navigation. Purchase a chart subscription for the area of your interest, download the map areas for offline use, and connect your onboard instruments for a complete experience. ● BASIC FEATURES - Switch between manual and auto route planning modes - Record your GPS tracks - Store and share your navigation data (markers, routes, and recorded tracks) - Display tides and currents predictions and simulations - Increase your safety with Anchor Alarm - Enable Live Sharing to interact with the Aqua Map community - Display points of interest from the "ActiveCaptain" and "Waterway Guide" communities ● EXPERT SUBSCRIPTION Note: this subscription does not include charts; it must be paired with a chart subscription. - Marine forecasts (wind, waves, currents, gusts, salinity, sea surface temperature + weather information for any point on the map) - Overlay satellite images on the charts - Advanced AnchorLink with anchorage mirroring and email/telegram notifications for greater peace of mind while anchored, even if you are away from the boat - Connect your NMEA instruments via WiFi (autopilot, depth sounder, wind sensor, compass, GPS) and use their data on the app - AIS with automatic collision detection - Route Explorer for real-time information on all elements along your route ● MASTER SUBSCRIPTION FOR THE BEST NAVIGATION EXPERIENCE Note: this subscription does not include charts; it must be paired with a chart subscription. - All features of the EXPERT subscription are included in the MASTER subscription. + LOCAL DATA: > US: Army Corps of Engineers surveys for safe navigation in shallow waters > US: LNMs and "List of Lights" navaids from the Coast Guard. > Canada: NAVWARNs from the Coast Guard. > France: Warnings, Notices and Regulations from the PING > Denmark: Warnings and Notices from the DMA > Western Australia: temporary Notices from the Transport WA   ● PURCHASE OPTIONS To access the charts, you need to purchase a chart subscription for the area of interest. Optionally, you can add the Expert subscription or the Master subscription to unlock extra navigation features and additional data. Subscription payments will be made through your account (Apple ID). The annual subscription will automatically renew unless canceled at least 24 hours before expiration. You can manage your subscription and disable automatic renewal in the account settings section after purchase. Terms of use: https://www.aquamap.app/terms-and-conditions Privacy policy: https://www.aquamap.app/privacy-policy