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
    Name or NavList Code:
    Email:
       
    Reply
    Re: Point and Shoot Camera CN Revisited
    From: Greg Rudzinski
    Date: 2015 Jan 26, 12:22 -0800

    The verdict is in with the point and shoot PowerShot camera once again failing badly for practical CN. Several series of calibrations were attempted showing large spreads (30') between sets. This was unexpect because all auto features were turned off and the auto focus was locked at infinity. My guess is that there is slop in the focal length so that every time the camera is turned on there is a slightly different focal length which defeats any efforts to calibrate. So back to the drawing board. There are some new point and shoot cameras that are on the expensive side whicht may have things tightened up enough for CN purposes. The Sony RX100 M3 caught my eye. When the used price on this model drops then I might give it a try.

    Greg Rudzinsk

    From: Greg Rudzinski
    Date: 2015 Jan 7, 11:17 -0800

    A revisit to my first unsuccessful efforts (8 years or so ago) at point and shoot camera CN using a Canon Powershot 10MP has me thinking that there may be a way to bring this type of affordable camera into the relm of practical CN. The still image settings offer three focus options. The infinity setting is the correct setting that will allow this inexpensive pocket camera to double as a useful sextant.  An artifitial horizon will be used for calibration observations to construct a table of minutes of arc per pixel at various pixel counts. Lightroom 5/Paint software works well for processing images and counting pixels. Solar film taped across half the lens does a good job for filtering the Sun.

    Greg Rudzinski



    Attached File:
       
    Reply
    Browse Files

    Drop Files

    NavList

    What is NavList?

    Get a NavList ID Code

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

    A NavList ID Code guarantees your identity in NavList posts and allows faster posting of messages.

    Retrieve a NavList ID Code

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

    Email Settings

    NavList ID 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