In "Dark Sky" mode only the currently selected fixture is active. The fixture is placed in the center of the cube at the center of the crosshairs. Light from the fixture is projected onto each internal face of the cube. Light from the fixture above 90 degrees vertical is represented in red. Light in the glare zone (default 80 to 90 degree) vertical range is shown in blue and light from 0 to 80 degrees vertical in green. As you will notice from the screen shot below, the light intensity is also shown.

The dark sky screen also provides the IES cutoff classification in the bottom right corner, the max candlepower, angles, and initial lamp efficacy rating in the bottom left corner. One word of caution when using the efficacy number. It is always wise to check the lamp and ballast manufacturer's latest data. Many fixtures may have been tested several years ago when the initial lumens were less. Factors such as this can effect a lamp meeting the efficacy requirements stipulated in California Title 24. The efficacy calculation will disappear from the screen if the initial lumens are changed in the fixture TAB.

The Glare Range settings allows the user to change the upper and lower angles of the light diplayed in blue on the "Darksky" screen. There is some debate in the lighting community as to the correct range of the angles. The range only effects the display and does not change any calculated information such as the cutoff classification.