Lamp: 100 watt A19, 120V, clear, Sylvania, filament CC-8, lamp vertical
------------------------------------------------------------------------
Volts .5 1 1.5 2 3 4.5 6 9 12 15 18 24 30 36 42 48 60 72 84 96 108 120 132 144 160
Amps .047 .083 .108 .126 .152 .177 .196 .227 .254 .280 .304 .350 .394 .433 .470 .505 .571 .631 .688 .740 .788 .834 .878 .921 .976-.980(?)
% Volts .4167 .8333 1.25 1.667 2.5 3.75 5 7.5 10 12.5 15 20 25 30 35 40 50 60 70 80 90 100 110 120 133.3
% Amps 5.63 9.95 12.95 15.1 18.2 21.2 23.5 27.2 30.5 33.6 36.5 42.0 47.2 51.9 56.4 60.6 68.5 75.7 82.5 88.7 94.5 100 105.3 110.4 117-117.5(?)
log(i/I)/ .525 .482 .466 .461 .462 .472 .483 .502 .516 .525 .532 .539 .541 .544 .546 .547 .547 .546 .540 .536 .538 --- .539 .544 .546-.561(?)
log(v/120)
color temp. K ~785 ~965 1115 1235 1345 1525 1665 1795 1905 2010 2190 2350 2490 2625 2750 2865 2975 3075 3190-3200(?)
log(ct/CT)/ .435 .420 .410 .404 .398 .392 .391 .389 .388 .387 .388 .388 .393 ~.39 ~.39 ---- ~.39 .388 .374-.385(?)
log(v/120)
~1-1.1E-4
lumens (approximately!) ~4-5 E-7 ~.003 ~.024~.11 ~.9 ~3.6 10 24 46 125 270 485 800 1220 1750 2400 3140 4200-4300(?)
log(lu/LU)/ 7.3-7.4 6.4 5.8 5.4 5.1 4.7 4.5 4.3 4.1 4.0 3.8 3.7 3.6 3.5 ~3.4 --- ~3.3 ~3.2 ~3.1(?)
log(v/120)
Lamp: 25 watt A19, 120V, clear, GE, filament CC-6, lamp vertical
------------------------------------------------------------------------
Volts .5 1 1.5 2 3 4.5 6 9 12 15 18 24 30 36 42 48 60 72 84 96 108 120 132 144 160
Amps .011 .0205 .0285 .035 .0455 .056 .0635 .073 .0795 .085 .090 .0995 .1075 .116 .124 .131 .146 .1595 .1725 .1845 .1955 .2065 .217 .2275 .240
% Volts .4167 .8333 1.25 1.667 2.5 3.75 5 7.5 10 12.5 15 20 25 30 35 40 50 60 70 80 90 100 110 120 133.3
% Amps 5.33 9.93 13.8 16.95 22.0 27.1 30.75 35.35 38.5 41.1 43.6 48.2 52.1 56.2 60.0 63.4 70.7 77.2 83.5 89.3 94.7 100 105.1 110.2 116.2
log(i/I)/ .535 .482 .452 .434 .410 .398 .394 .401 .415 .428 .438 .453 .470 .479 .487 .497 .500 .507 .51 .51 .51-.52 --- .52 .52-.53 .52-.53
log(v/120)
color temp. K 2550
Lumens (approximately!) 210
Lamp: 25 watt T10, 120V, clear, GE, filament C-8, lamp vertical
------------------------------------------------------------------------
Volts .5 1 1.5 2 3 4.5 6 9 12 15 18 24 30 36 42 48 60 72 84 96 108 120 132 144 160
Amps .008 .012 .015 .018 .023 .029 .0345 .0445 .053 .061 .068 .0815 .0935 .1045 .1145 .124 .1425 .1585 .1735 .188 .201 .214 .226 .238 .252
% Volts .4167 .8333 1.25 1.667 2.5 3.75 5 7.5 10 12.5 15 20 25 30 35 40 50 60 70 80 90 100 110 120 133.3
% Amps 3.74 5.61 7.00 8.41 10.75 13.6 16.1 20.8 24.8 28.5 31.8 38.1 43.7 48.8 53.5 57.9 66.6 74.1 81.1 87.9 93.9 100 105.6 111.2 117.8
log(i/I)/ .600 .602 .607 .605 .605 .608 .610 .606 .605 .604 .604 .600 .597 .596 .596 .596 .586 .587 .587 ~.58 .58-.59 --- ~.58 .58 .57
log(v/120)
color temp. K 2550
Lumens (approximately!) 260
This was done with the "Properties of Tungsten" table in the "Handbook of Chemistry and Physics", published by the Chemical Rubber Publishing Co.
In addition, plenty of interpolation was done.
Color temperature at full voltage for 100 watt 120V 750 hour A19 was assumed
to be 2865 K because web searching into this matter got more hits and from
sources that I considered more credible than other figures such as 2850, 2860
and 2870 K. Sources claiming 2865 K include Kodak.
Color temperature of coiled-coil filament in gas-filled bulb was assumed to be
halfway between the actual temperature and the color of a straight tungsten wire
in vacuum at the same actual temperature according to the table.
Actual temperature at voltages other than full voltage were worked from
filament resistance as a function of actual temperature according to the
above "Properties of Tungsten" table.
Color temperature of other lamps at full voltage largely come from color
matching them to a 100 watt 120V A19 that is powered by an adjustable
voltage power supply and use of my data for the above 100 watt lamp.
It is to be noted that the temperature is not completely uniform throughout the filament. It is also to be noted that the temperature profile of the filament varies with temperature since heat loss from radiation and conduction vary differently with temperature. As a result, color temperature and lumen figures are only roughly approximate, especially at more extreme voltages.
Lumens:
Color temperature was plugged into a homebrew BASIC program that has the
blackbody function and the photopic function. "Color emissivity" (ratio of
brightness of a given incandescent surface to a blackbody surface at the same
color temperature) for a coiled-coil filament in a gas-filled bulb was assumed
to be the square root of that shown in the "Properties of Tungsten" table
for a straight wire in vacuum, for a given actual temperature. Color emissivity
varies slightly inversely with temperature. This permits working of lumens at
various filament temperature given color and assumed actual temperature and
manufacturer's stated lumens at full voltage.
Brightness according to the brightness column in the "Properties of Tungsten"
table varies even slightly more drastically with temperature than according to
my homebrew BASIC program.
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