When calculating the beam diameter of a given fixture you multiply its Multiplication Factor (MF) X the throw distance. The MF for many common beam spreads and lens sets are listed below. Please note these are not precision measurements, only approximate measurements. Example for a 5° fixture at a distance of 50' you would multiply 50 X .09 to find a beam diameter of 4.5'.

8" Lens	6" Lens	S4/Leko	Phoenix/ Pacific	MF #	Beam at 10'	Beam at 25'	Beam at 50'	Beam at 75'	Beam at 100'
		5°	5°	0.09			4'-6"	6'-9"	9'-0"
8" X 14"	6" X 22"	10 °	10 °	0.17			8'-6"'	12'-9"	17'-0"
8" X 8"	6" X 16"	19 °	20 °	0.32	3'-2"	8'-0"	16'-0"	24'-0"
	6" X 12"	26 °	30 °	0.46	4'-8"	11'-6"	23'-0"
	6" X 9"	36 °	40 °	0.64	6'-5"	16'-0"
	4.5" X 6"	50 °	50°	0.93	9'-4"
			90 °