Archive for constellation

Bright nebulae at Milky Way core

Posted in Astrophotography with tags , , , , , , , , , , , , on 2011/07/04 by computerphysicslab

Summer views of Milky Way are spectacular because the galaxy bulge is brighter and broader than its spiral arms visible the rest of the year. Located near Sagittarius and Scorpius constellations, the bright nebulae and dark lanes of the area creates a beautiful contrast in brightness and colors.

This picture is a 4-pane mosaic ensambled with free software Fitswork 4.40. Every pane is a 10 minutes exposition through a 55mm lens attached to a Canon EOS 450d (Rebel XSi) DSLR camera, mounted over a motorized equatorial mount, Sky Watcher EQ6.

Mosaic - Sagittarius Scorpius - Milky Way core

A full resolution picture is available at AweSky

Auriga and Moonlight

Posted in Astrophotography with tags , , , , , , , , on 2009/10/10 by computerphysicslab

This is a set of 71 single shots of 10 seconds each one to the Auriga constellation on 2009-10-08. The Moon was located at its south and its brightness is visible on the edge of the image and on the background gradient. The single frames were recorded using a Canon Rebel XTi (EOS 450d) and a conventional EF 18mm lens. The Kids is a triangle of stars on the upper side of Auriga constellation.

Auriga-Moon-18mm-71x10sec-Wordpress

Orion in Spring

Posted in Astrophotography with tags , , , , , , , , on 2009/04/28 by computerphysicslab

Orion constellation may be difficult to sight in Spring due to its low altitude near the bright west horizon at dusk. Nevertheless I took one subframe of 8 seconds of exposition under ISO-400 applying my new Canon EOS 450d plus 18-55mm lens.

With Paint Shop Pro I subtracted the background gradient due to dusk light. There is visible a pine branch below.

Orion Constellation and pine tree

Background substraction

Posted in Astrophotography with tags , , , , , , , on 2006/03/25 by computerphysicslab

Astrophotos taken in light polluted skies use to show a noisy gray background that should be avoided mainly for aesthetic reasons, and also to gain contrast in deep-sky objects. Using some image software like Paintshop Pro or Photoshop it is simple to correct the image in 4 steps:

1.- Make a copy of the image.

2.- Level the copy from zero to the highest background noise value. This way bright stars will appear as dim as background.

3.- Gaussian Blur the copy.

4.- Substract the copy to the original picture. You may add a small offset to the substraction if the background removal is very hard.

Here is an example with Orion constellation:

Background Substraction

Orion belt

Posted in Astrophotography with tags , , , , , , , on 1996/03/25 by computerphysicslab

Orion is the most important Winter constellation in Northern Hemisphere. In its center we find the “Orion belt” and beneath, the “Orion sword”. The nebulas located in the area show red colors: horsehead, flame and M42 are visible in this shot.

Orion belt & sword