Welcome to the NavList Message Boards.

NavList:

A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding

Compose Your Message

Message:αβγ
Message:abc
Add Images & Files
    or...
       
    Reply
    Re: Sun Shots Through Clouds
    From: Lu Abel
    Date: 2014 Nov 2, 16:58 +0000
    What is the iPhone app, Greg?  

    I have seen navigation apps (not necessarily celestial) that range from really good to junk. Would love to hear of apps that people think are really good ones.

    An example:  One of the centerpieces of traditional coastal navigation is taking bearings.   But anyone who has tried this from a recreational boat (vs a cruise ship) knows that boats bounce around a lot and it's very hard to get an accurate bearing.   I found an app "Theodolite" that imposes compass direction and even tilt onto a camera image.  So I can snap a shot of a distant object and get its bearing.  With a name like "Theodolite" it isn't touted as a navigation app, but it seems excellent at something that challenges us all.


    From: Greg Rudzinski <NoReply_Rudzinski@fer3.com>
    To: luabel{at}ymail.com
    Sent: Saturday, November 1, 2014 6:56 PM
    Subject: [NavList] Re: Sun Shots Through Clouds

    Sam,
    No need to be perfect with the preset. Time can be 10 minutes off and still get the Sun into the field of view. I use a phone app to calculate the Hc for my assumed position. The app has an almanac and a chronometer so by pushing the now button an Hc pops up which I double to set the artificial horizon sextant preset. If using 229 / 249 the the nearest degree of latitude, LHA, and declination should get the Sun into the field of view.
     
    Greg Rudzinski
     


    From: Samuel L
    Date: 2014 Nov 1, 12:18 -0700
    Greg,
    Preset Altitude is something we've just begun to experiment with. So far, using an AH, we can see both images of the Sun but not exactly superimposed or Upper Limb or Lower limb touching.
    Tell me if this is right or wrong....or the correct way to go about it.
    - determine the exact time you want to take the Sun sight and calculate Hc
    - preset the Sextant to the calculated Hc (when using an AH multiply Hc times 2 and subtract or add SD depending upon which limb is being observed).
    What do you think? What method do you use?
    Thanks,
    Sam L.


       
    Reply
    Browse Files

    Drop Files

    NavList

    What is NavList?

    Join NavList

    Name:
    (please, no nicknames or handles)
    Email:
    Do you want to receive all group messages by email?
    Yes No

    You can also join by posting. Your first on-topic post automatically makes you a member.

    Posting Code

    Enter the email address associated with your NavList messages. Your posting code will be emailed to you immediately.
    Email:

    Email Settings

    Posting Code:

    Custom Index

    Subject:
    Author:
    Start date: (yyyymm dd)
    End date: (yyyymm dd)

    Visit this site
    Visit this site
    Visit this site
    Visit this site
    Visit this site
    Visit this site