A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
From: Greg Rudzinski
Date: 2014 Oct 24, 11:02 -0700
The 400mm telescope should get it done for both eclipse and Jupiter's moons. You should use at least 10 mega pixel digital camera. For image processing I use Adobe Photoshop Lightroom 5.3 and then measure pixels with Windows 7 paint brush tool. Warning-there is a learning curve for getting the most out of Lightroom 5.3
If a zoom lens is used then it has to be calibrated for each image. Not convenient. For filtering I use linear polarizers with one of the polarizer filters flipped in the holder so that the pair acts as an adjustable neutral density filter. I'm sure solar film will work on your 400mm telescope objective lens. Start at f22, ISO 100, 1/4000 sec, infinite focus.
The classic astronomers must have measured realtime with something similar to a theodolite. I'm not sure when photo astronomy first started ...1850s?
From: Francis Upchurch
Date: 2014 Oct 24, 17:53 +0100