Welcome to the NavList Message Boards.


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

Compose Your Message

Add Images & Files
    Re: 229 and 249
    From: Brad Morris
    Date: 2013 Jul 29, 13:36 -0400

    One possible reason is where the images are to be viewed.

    When you look at an image on a display, its typically at a fairly low resolution.  (Exceptions exist).  Extra resolution in the image does not appreciably alter how it is presented on the screen, so the detail afforded in the high resolution (and size) file is wasted.

    Therefore if either is examined on a display, no perceptible difference will be noted.

    If, however, you intend to print and view the image on paper, higher resolutions are indicated.  It is highly likely that the Celestaire image is intended to be printed.


    On Jul 29, 2013 12:35 PM, "William Hawes" <williamhawes@rogers.com> wrote:

    Anyone got any idea why the Celestaire download is so large?

    The NGA (National Geospatial-Intelligence Agency) 249 Vol 1 Epoch 2010 at


    is 351 pages and its size is 4.97 MB.

    The Celestaire 249 Vol 1 Epoch 2015 at


    is 353 pages but is over 34 times larger at 171.29 MB.

    Quality of both documents seems to be about the same. How come the Celestaire document is so large?


    NavList message boards and member settings: www.fer3.com/NavList
    Members may optionally receive posts by email.
    To cancel email delivery, send a message to NoMail[at]fer3.com

    View and reply to this message: http://fer3.com/arc/m2.aspx?i=124734

    Browse Files

    Drop Files


    What is NavList?

    Join NavList

    (please, no nicknames or handles)
    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 Settings

    Posting Code:

    Custom Index

    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