What is the best lens focal length for photographing the total solar eclipse? Well, there really isn’t a correct answer to that question. There are many factors involved, so let’s outline some options for different types of cameras and budgets.
Above: The Hinode satellite X-ray telescope mission captures the January 6, 2011 solar eclipse. © JAXA/NASA.
Size of the Sun
Most of us think the sun is huge in the daytime sky. Even when masked by clouds, those days we can see the ball of the sun through a thin layer of clouds, the sun looks large. But even though the sun is 864,000 miles across (109 times the size of Earth), the fact that it is approximately 93 million miles away means that it appears to be almost the same size as the moon in our skies.
If you do not believe me, just think about the solar eclipses you have seen photographed in the past. You will see how the moon, during an eclipse, at or near its closest approach to Earth (perigee), blocks out the entire sun. (When the moon is farther from Earth [apogee], the result is a partial blockage of the sun during what is called an annular solar eclipse.) The relative sizes of the sun and moon, and their relative distances from Earth, are what make eclipses so cool for those of us on Earth.
So, the sun is moon-sized in the daytime sky. Got it. But, wait! There’s more.
During the totality portion of a solar eclipse, when the umbral shadow passes over the observer on Earth, the sun’s corona, usually invisible to the naked eye, is suddenly visible and it extends well away from the surface of the sun. So now, the sun and its usually invisible corona are larger than the sun alone.
... Via B&H explora - All posts https://ift.tt/2eTTt8P
0 Reviews:
Post Your Review