Sight reduction
- Astronavigation
Sight reduction:
- Marcq Saint Hilaire Line of Position, intercept method (p=Ho-Hc, Zn)
- Observed altitude Ho by nautical almanac data
- Local hour angle (LHA)
- Plot of the LoP on Google maps
Sight reduction is the process of deriving from a sight the information needed for establishing a line of position.This app is a calculator to get the intercept from the assumed position of the observer AP(latitude, longitude), the geographical position of the celestial body observed, GP(Dec, GHA), and its corrected altitude Ho.Manual and examples in the developer's website.
Ref: https://en.wikipedia.org/wiki/Sight_reduction
Category : Travel & Local
Reviews (10)
Great app, but I have two points to mention. 1) When I twist the smartphone (Samsung S-7) to horizontal all the previous LOPs disappear. So I have to re-enter all that data. Argh! 2) It's seemingly impossible to enter a negative IC (instrument correction). The work-around I use is to enter a negative value in some other APP and then copy/paste into the IC correction space. In conjunction with the Nautical Almanac app that I have this is a near perfect combination. I'm not giving up my GPS units, but it sure is nice to have some old-school stuff around as a back-up.
So easy to use. Accurate fix.
Looks great on the surface.... No place to enter the time of the sight. Really Lame. DON'T BOTHER
Very Helpful! Thanks
Ideal for saving time plotting a fix or simply checking your work. Recommend using the developer's almanac app alongside this one. Thanks!
Can be used to yuor good correction..wow
Great!!! Save a lot of time and a lot effort for a bunch of paper works required now a days on a merchant shipping... Thanks.
Very useful apps. Thanks
Great references
This app is useless for navigation because you can't specify the time at each sight. Would be very handy if there was a time perameter in the LOP box.