Creating 3D Effects
(please refresh this page often)

Introduction:   Two images placed side by side will create a 3D effect if stars or nebula regions are shifted in one image relative to the other, and if you then cross your eyes when viewing.  Examples of this effect can be found in several images on my website, including the the Orion Nebula, the Elephant Trunk, IC1805, and the Cone Nebula.  The inspiration for making 3D astrophotography images comes from an article in Sky and Telescope (December 2003), which featured the 3-D work of Akira Inaka.    Many have asked me how my 3D images were created, and specifically how I achieved the shift in Photoshop.  The technique is very easy and is described below.

The following directions apply to users of Photoshop:

1.  Open your image in Photoshop and convert to 8 bit mode (necessary for using the "distort" function).

2.  Orient your image vertically, so that it is taller than it is wider.

3.  Duplicate your image into another layer.

4.  Increase your canvas size to accomodate the two images, and place them side by side.

5.  You will now only work on the right hand image, leaving the left hand (original) image untouched.

6.  To bring a star into the foreground, it must be shifted to the right.  To place it into the background, it must be shifted to the left.  The use of the "distort" function makes this easy to accomplish (see next step).

7.  Identify a star that you wish to shift.  Encircle it using the lasso tool with a feather of 5 pixels (experiment with this).  Go to "Filter, Distort, Shear".  Adjust the vertical shear line as desired (i.e., move to right or left).  The more you move the line, the more shift you will create.  Experiment with this to achieve the desired effect for a given star or nebula field.

8.  You may wish to encircle the perimeter of a shifted nebula region and apply a less aggressive shift to this area, in order to achieve a pleasing transition between shifted and non-shifted regions.

The technique takes practice but is not difficult to master.  Have fun with it!


All Images and Content  Copyright Steve Cannistra unless otherwise stated.

Back to Astrophotography Page