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An Alternate Use For GradientXTerminator


GradientXTerminator was created by Russ Croman to remove gradients from astronomy related images. The procedure on this page uses the software to enhance a dark area of an image. This for the "pretty picture" astro-artist and not the faint of heart purist.

Figure 1 shows an image that has a darker region of nebula on the right side that is difficult to show without making the left side too bright.

The first step, with PhotoShop, is to copy the image to a new layer.  This is easily done with the Ctrl J shortcut.  Then use the Lasso Tool, to select the bright part of the central nebula. See Figure 2.

Next, invert the selection... see Figure 3.  So far we are following the standard GradientXTerminator  process.

Now execute GradientXTerminator with the Detail set to Fine and the Aggressiveness set to High.  See Figure 4.

Figure 5 shows the result after executing GradientXTerminator. 

The final step is to set the blend mode to Lighten and flatten the image. See Figure 6 for the final result. You can blink Figure 6 back and fourth from the starting image to the final by rolling your mouse over the image.


Fig. 1


Fig. 2


Fig. 3


Fig. 4

fig. 5


Fig. 6