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1316 Chapter 15: Lights and Cameras
Tip: Should you wish to edit the mr Physical
Sky parameters, an easy way to access them is
to open the Material Editor (press
M )and
then drag the Environment Map button from
the Environment panel > Common Parameters
rollout to a material slot (sample sphere) in the
Material Editor. When prompted for the copy
method, choose Instance.
8. Open the Render Scene dialog (page 3–2)
(
F10 ) to the Indirect Illumination panel and
turn on Enable Final Gather. Choose the Draft
preset as a starting point.
Impor tant: Don’tforgettoturnonEnableFinal
Gather when using Sun & Sky, since the skylight is a
form of indirect light, which can be rendered only
with the help of Final Gather. If t his is not done, Sun
shadows will be unnaturally dark or black rather tha n
bluish, as they should be.
9.
Render with Sun & Sky. To specify different
times, dates, and locations in the Daylight
system for different effects, use t he Motion
panel>ControlParameterssettingsorturnon
Manual Override to place the sun by hand.
Tip: Adjust t he Bri g htness and Contrast of the
Logarithmic Exposure Control for a pleasing
image.
Common Parameters
Cer t ain parameters do the same things in
mr Sun, mr Sky, and mr Physical Sky. For
physica l correctness, it is necessary to keep these
parameters in sync with each other in all three
elements. For example, a sun with a d i f ferent Haze
value than the sky cannot be g uaranteed to be
physically plausible.
For this reason the concept of parameter
inheritance is included. Both the mr Sun light
and the mr Physical Sky shader have check
boxes labeled “Inherit from mr Sky” that are
on by default. When these are on, the common