Following older posts on astrophotography where I have shown Lyra and Andromeda, here I present Canis Major, the constellation of the brightest star in the sky, Sirius. The M41 open cluster is seen clearly in the image. It has 90 seconds of total exposure time, a focal length of 30mm, and opening of f/4.0. I [...]
Archive for November, 2011
Sirius and M41
Posted in Astronomy, Astrophotography, Photo, tagged constellations on November 25, 2011 | Leave a Comment »
Python-histogram-histtype=’step’
Posted in Python, tagged histogram on November 15, 2011 | Leave a Comment »
Using histogram or better to say a probability density function (PDF) is a daily task for many people in science and engineering. Making a histogram is the same as a PDF: one just needs to add a keyword “normed=True”. Since making histogram is a standard example in Matplotlib, I do not repeat it here in [...]
Andromeda and Triangulum Galaxies
Posted in Astronomy, Astrophotography, Photo, tagged constellations on November 11, 2011 | 1 Comment »
In a seri of posts, I plan to show some of my simple astrophotos. Almost all of them were taken without any special equipment, e.g. telescope. I used only a camera, a tripod and a cable release. Using my Canon EOS 400D camera, on Sep 2010, I have recorded 24 times 15 seconds exposure without [...]
Green Flash
Posted in Astronomy, Astrophotography, Photo, tagged solar on November 1, 2011 | Leave a Comment »
Green flashes and green rays are optical phenomena that occur shortly after sunset or before sunrise, when a green spot or rim is visible above the sun. The reason is that for different part of the solar spectrum, i.e., different colors, there are different refraction index in the atmosphere. That means the earth atmosphere plays [...]
