mr Sun
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Daylight system Modify panel Daylight Parameters rollout Sunlight drop-down list mr Sun

The mr Sun light is intended for use in the mental ray Sun & Sky combination. This topic mainly provides information on parameters unique to this component. A number of mr Sky parameters are common to all three Sun & Sky components. For some of those parameters, this topic provides a brief explanation plus a link to the main topic with additional details.

TipYou can view the Sun & Sky combination in a viewport, which makes adjusting parameters fully interactive. For details, see this procedure.
See Also


mr Sun Basic Parameters rollout


Turns the mr Sun light on and off. Default=on.


A scalar multiplier for the light output. Default=1.0.


Applicable only when you add an mr Sun light directly to the scene via Create panel Lights Photometric, rather than as part of a Daylight system. When on, the light is targeted and you can change the target distance by moving the target. The distance between the light and its target is displayed to the right of the check box. When off, you can set this value directly. Default=on.

Shadows group


Toggles shadowing for the light. Default=on.


The softness of shadow edges. The default value of 1.0 accurately matches the softness of real solar shadows. Lower values make the shadows sharper and higher values make them softer.


The number of shadow samples for the soft shadows. If it is set to 0, no soft shadows are generated. Default=8.

Inherit from mr Sky group

Notemr Sun can inherit parameters from mr Sky even if the latter is off.
Inherit from mr Sky

Uses the equivalent settings from the mr Sky Parameters rollout for the remaining mr Sun Parameters rollout settings. Default=on.

For further information, see Common Parameters.

Nonphysical Tuning group

These controls are available only when “Inherit From mr Sky” is off.

Red/Blue Tint

Provides artistic control over the redness of the sky light. The default value of 0.0 is the physically correct value (calculated for a 6500K whitepoint), but can be changed with this parameter, which ranges from –1.0 (extremely blue) to 1.0 (extremely red).


Provides artistic control over saturation of the sky light. The default value of 1.0 is the physically calculated saturation level. Possible values range from 0.0 (black and white) to 2.0 (extremely high saturation).

mr Sun Photons rollout

Use these settings to focus global-illumination photons on an area of interest. For example, if you’ve modeled a huge city as a backdrop, but are rendering only a room interior, you probably don’t want mental ray to shoot photons over the entire city, with the result that only a few will find their way into the room.

Use Photon Target

When on, uses the Radius setting with respect to the light target.


Sets the radial distance from the target in which the mr Sun casts GI photons.