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Use Sun – If on a Sun light is used in all draft & quality renders. The direction of the sunlight points to the 0,0,0 point of the drawing.
Sun Shadows On – If on 
Intensity: sets the power of the sunlight It takes values from 0 to 9999, with a default of 1.
Shadows – If checked the sun light casts shadows.
Show Ground Plane – If on a ground plane (z = 0) is displayed (see SketchUp) this ground plane acts as a shadow catcher but is otherwise transparent.
Use System time – If Use File Latitude, Longitude and Time – if selected system setting and drawing parameters are used to calculate the location of the sun.System time and Geo-Location: If selected the date and time is derived from the computer clock
Use Custom Time – If selected the user specifies a date and time.
Set Custom Time – the user directly enter a time (hours and minutes) in a 24 hour format.
Set Custom Date – The user can use the slider to set the date (365 days ( see SketchUp)) or
Day – the user can explicitly set the day
Month – the user can explicitly set the month
Use Azimuth and Angle – If selected the used and the location is specified by Geo-Location
Use Specified time and Geo-Location: If selected the date and time and time zone (GMT+/-) are user specified and the location is specified by Geo-Location
Date: Sets the date.
Time: Sets the time.
Timezone: Sets the timezone as relative plus or minus to Greenwich Mean Time (GMT)
Custom: If selected the uses may directly specify the Azimuth and Angle as an alternative to LAT LONG and TIME.
Azimuth
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: The user can specify the Azimuth from 0.00 to 360
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Angle
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: The user can specify the Angle from 0.00 to 90
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