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MainStage Beam Analyzer

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How to use sheet:

1) Select what fixture you want to use

2) Select what lamp will be in that fixture

3) Know the distance that the fixture will be from the object it is illuminating

4) Enter the throw distance in the "Throw Distance" box

The form will calulate the size of the field and beam diameter for that fixture at that distance. It will also give you an estimated intensity in footcandles for that fixture at that distance with that lamp.

What is the distance: (in Feet)


100 fc is a good reference base for stage intensity

45 fc is a good reference base for houselight intensity

Beam Diameter X: Beam Diameter Y:

Beam size radius is measured from the Center of beam to 50% intensity

Beam size diameter is a good estimator for gobo image size 


Designed and Coded for MainStage by:Kyle Olson