NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Digital Camera Celestial Navigation
From: Marcel Tschudin
Date: 2008 Jul 5, 01:20 +0300
From: Marcel Tschudin
Date: 2008 Jul 5, 01:20 +0300
Frank asked: "How reliably can one measure the flattening using a digital camera? A few tenths of a minute of arc??" Just to give you an idea (using 6x optical zoom and magnifying the photo 4x): with the sun's upper limb about 2.5 degrees above the apparent horizon Sun diameter horizontal: 125mm +/-about 0.5-1mm, Sun diameter vertical: 120mm +/-about 0.5-1mm The value for the sun's (horizontal) diameter at that time is 0.525� --~--~---------~--~----~------------~-------~--~----~ Navigation List archive: www.fer3.com/arc To post, email NavList@fer3.com To , email NavList-@fer3.com -~----------~----~----~----~------~----~------~--~---
