III. LightWave’s gamma tends to be a bit darker than other renderers by
default, due to its “linear” gamma curve. You can easily add a gamma
adjustment as a post-processing image filter to adjust this gamma to
your needs. Neither the included gamma adjustment filter or the
Gamma slider in the Image Editor will flatten your ranges down into
non-FP data, allowing you to save adjusted images into HDR file formats
even after processing. We suggest processing the gamma of all of your
output images, and that gamma adjustment is a good way to pull out
seemingly imperceptible radiosity effects. Following is an example of
that:
Images by Kenneth Woodruff
A. A raw LightWave render. B. A gamma-adjusted version of the render.
Notice that the column in the lower left is
now very distinct from the shadow area from
which it was previously... indistinct.
C. Should I post- or pre-adjust?
I. As with most situations, it depends. In some cases, you might want to
pre-adjust an HDR image so that you can make other necessary adjust
-
ments to your scene without having to process the images just to see
the effects of a change to your surfacing. Using straight HDR files, at
times you may be confronted with an image that seems to be completely
black with some bright spots, when it actually contains a wealth of detail.
In this case, adjusting the range of the HDRI map to something that is
easier to see without further tweaking may be in order. You may, how
-
ever, want to maintain that huge range to allow for a wider range of
possible final exposures. As for post-adjustments themselves, it’s often
best to render raw images and process them later, so that you do not
waste time rendering images again just to make a slight adjustment, or if
a client wants to see an image represented with a type of film that tends
towards a darker tonal range. Also, while you may be a purist, preferring
to tweak the lighting of a scene to perfection instead of relying on
post-adjustment, in a production situation it’s sometimes easier to run
an image through a post-process and move on. Some studios render
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