Site hosted by Angelfire.com: Build your free website today!

 

 

 

 

 

 

 

 

Galaxies in Virgo, with the massive galaxy M86 at the centre of the image, and M84 to the right.  These galaxies are members of the Virgo Cluster, together with the brighter galaxies in this image, eg NGC4402.  The negative image above, however shows many background galaxies that are much further away.  I count 28 galaxies in this image!

NGC4402 clearly shows its dust lane, and higher resolution images than mine show that it is 'falling' into the Cluster resulting in gas being stripped away on its south (bottom) side - somewhat like a flying saucer entering the atmosphere...

The pair of galaxies to the left, NGC4435 and 4438 are distorted from mutual interaction, and are called 'The Eyes'.

On the negative it is apparent how large M86 is.  At almost 10 arcmins, it is about third the diameter of the full moon.  Deeper images by David Malin (using a slightly larger telescope and darker skies than mine) show it to be even bigger.

Image info

Telescope:  Celestron 9.25" Schimdt-Cassegrain at f/6.3

Focus:  Prime focus

Filter:  Celestron LPR

Mount:  Vixen GPD with Skysensor2000

Camera:  Modified Canon EOS 300D, at ISO400

Guiding:  700mm refractor guidescope, SAC7 camera, autoguided with Guidedog software

Exposure:  Total 45 mins (15 x 180s)

Date:  10th February 2005

Processing:  RAW file conversion, Offset and Dark subtraction, flat fielding, registering and stacking done in IRIS.  Curve stretching and colour saturation enhancement by Luminance Layering in Photoshop CS.

Comments

Processed using flats produced using a new light box that I have built.  Flat evenness is still not perfect - see the darker corners in the highly contrast stretched negative image.

On the plus side, it's remarkable how modern digital techniques can cut through light pollution.  Even in the mag 4 (at very best) skies of Singapore it is possible to detect mag 19 galaxies.  Stars down to mag 19.6 (USNO B1.0) imaged.

 
 
© Copyright 2003 to 2012, by TG Tan.  All rights reserved.  Copyright exists in all original material available on this website.  This material is for your personal individual, nonprofit use only.  Redistribution and/or public reproduction of this material is strictly prohibited without prior express written permission from the author.