gcpsoundlight
Active Member
Basic rule down one side, both metric and imperial
PRG cable length code.
I added a poll to the top of this to help us figure out which measurement marks would be most useful. Please vote for two, as that will help us decide the most useful combination. Remember this is a credit card so it's only 3" long.
90 degree= 1.88
70 degree= 1.40
50 degree= .93
36 degree= .65
26 degree= .46
19 degree= .31
10 degree= .178
05 degree = .119
(from Lighting Designers Page ) [With better formatting. And valid data--ignore the rubbish constant of .018 on the page referenced--it's been disproven elsewhere. The correct method to calculate is to use the formula Beam diameter = distance * (2 * tan (beam angle in degrees / 2)). ]----------------------------------------------------------------------
4. WIDTH OF LIGHTING BEAM - AT ANY SPREAD ANGLE & DISTANCE
----------------------------------------------------------------------
D.in| ANGLE (in degrees)
ft.| 10 15 20 25 30 35 40 45 50 55 60
|------------------------------------------------------------------
5 | .9 1.4 1.8 2.3 2.7 3.2 3.6 4.1 4.5 5.0 5.4
10 | 1.8 2.7 3.6 4.5 5.4 6.3 7.2 8.1 9.0 9.9 10.8
15 | 2.7 4.0 5.4 6.8 8.1 9.5 10.8 12.2 13.5 14.9 16.2
20 | 3.6 5.4 7.2 9.0 10.8 12.6 14.4 16.2 18.0 19.8 21.6
25 | 4.5 6.8 9.0 11.3 13.5 15.8 18.0 20.3 22.5 24.6 27.0
----------------------------------------------------------------------
30 | 5.4 8.1 10.8 13.5 16.2 18.9 21.6 24.3 27.0 29.7 32.4
35 | 6.3 9.5 12.6 15.8 18.9 22.0 25.2 28.4 31.5 34.7 37.8
40 | 7.2 10.8 14.4 18.0 21.6 25.2 28.8 32.4 36.0 39.6 43.2
45 | 8.1 12.2 16.2 20.3 24.3 28.4 32.4 36.5 40.5 44.6 48.6
50 | 9.0 13.5 18.0 22.5 27.0 31.5 36.0 40.5 45.0 49.5 54.0
----------------------------------------------------------------------
55 | 9.9 14.6 19.8 24.8 29.7 34.7 39.6 44.6 49.5 54.5 59.4
60 | 10.8 16.2 21.6 27.0 32.4 37.8 43.2 48.6 54.0 59.4 64.8
65 | 11.7 17.6 23.4 29.3 35.1 41.0 46.8 52.7 58.5 64.4 70.2
70 | 12.6 18.9 25.2 31.5 37.8 44.1 50.4 56.7 63.0 69.3 75.6
75 | 13.5 20.3 27.0 33.8 40.5 47.3 54.0 60.8 67.6 74.3 81.0
----------------------------------------------------------------------
80 | 14.4 21.6 28.8 36.0 43.2 50.4 57.6 64.8 72.0 79.2 86.4
85 | 15.3 23.0 30.6 38.3 46.0 53.6 61.2 68.9 76.5 84.2 91.8
90 | 16.2 24.3 32.4 40.5 48.6 56.7 64.8 72.9 81.0 89.1 97.2
95 | 17.1 25.7 34.2 42.8 51.3 59.9 68.4 77.0 85.5 94.1 102.6
100 | 18.0 27.0 36.0 45.0 54.0 63.0 72.0 81.0 90.0 99.0 108.0
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I would vote for the list. most folks have a calculator so multiplication is fairly easy. A chart would take up a lot of precious roomWhich would be preferable,
a) a LIST of the multiplication factors:
OR
b) a CHART of angles and distances:
?
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