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: Comet Donati above Paris 1858
    From: Robin Stuart
    Date: 2019 Apr 21, 11:56 -0700

    Brad,

           As the introductory quotation in my post was supposed to make clear, my remarks were limited solely to the capabilities of modern cameras to capture the night sky with relatively short exposures. Whether foreground objects are also captured depends on the level ambient lighting.

    You stated:

     “It is for this reason we never see stars simultaneously with the moon landings.  The foreground effectively washes out the background.  Image after image from the surface of the moon, with no stars in the background.”

    Since the Apollo astronauts had the good sense to land during daylight hours, exposure times were quite short. If they had stuck around after lunar sunset (luckily none of them had to) and tried taking photos of stars with the same exposure and aperture as they had used in daylight they wouldn’t have captured any stars either. Try pointing an old film camera at the sky at night on Earth with, say, a 1/100s exposure and see how many stars you pick up!

    Robin Stuart

       
    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