Postprocessing Images
A guide on how to postprocess images to get the most out
of Terragen
Antialiasing
This advice is mostly obsolete now
that Terragen includes anti-aliasing support. However,
this advice can still improve the image quality in some
cases. When you render an image in Terragen, there
is almost always a sharp divide between land and sky
(fig.1). The way to overcome this is to render the image
double size and then resample the image
to a lower size - preferably half size. This smoothes out
the sharp edges, making the images look better. Most
better paint programs (Photoshop, Paint Shop Pro, etc.)
offer this feature.
|

not resampled - high detail but jagged
edges. |

using resampling - lower detail, but
no jagged edges. |
Brightness/Contrast/Histogram changes
Changing the colour balance is generally not a good
idea with Terragen images, as Terragen tries to emulate
real-world lighting already, and colour detail can be lost. It is
far better to experiment with Exposure/Lighting/Gamma settings instead.
However, some nice effects can be gained by using (post-render)
gamma correction with values between 0.5 and 1.
Lens Flare
This will be an integral part of Terragen in the future, or
will be provided through plugins. For now, you have to add lens
flare manually using programs such as Photoshop. The key here is
to make it subtle! Equally important is to choose the flare's
origin point accurately. Usually, in Photoshop I will use between
50% and 75% brightness, or I will fade in a 100% bright flare.
Unsharpening
"Unsharpening" is a sharpening
process that applies itself more to higher-contrast areas
- which makes it perfect for bringing out details in
craggy landscapes. I find it best to use a softening
filter first, and then apply the unsharpening with a
radius of around 1.5 pixels. I generally do this before
antialiasing the picture. |

no unsharpening |

with unsharpening |
And Finally...
The best way to approach any post-processing of Terragen
images is - realism. Always try to keep the realism in
your pictures and you should get good results.
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