Sixty Candles
The bulb on Emma's birthday cake represented the candles*, for sheer photo fun! Also there's a lot less heat on the cake surface ;)
***...
Read more
The bulb on Emma's birthday cake represented the candles*, for sheer photo fun! Also there's a lot less heat on the cake surface ;)
***
Some light sources are rated in various different units, such as *candlepower or watts. To be able to compare different types of light sources, it would be necessary to convert between these types of units.
The short answer is, you cannot. Unless the manufacturer already has calculated both candlepower and watts, you're pretty much out of luck. However, here are some units, and quite unrelated to birthdays!
- candlepower
One candlepower is the radiating power of a light with the intensity of one candle. Replaced by the candela in 1948, it is still in common use. 1 candlepower is equal to about 0.981 candela.
- candela
The standard unit for measuring the intensity of light. The candela is defined to be the luminous intensity of a light source producing single-frequency light at a frequency of 540 terahertz (THz) with a power of 1-683 watt per steradian, or 18.3988 milliwatts over a complete sphere centered at the light source.
- lumen
The standard unit for measuring the flux of a light being produced by a light source. One lumen represents the total flux of light emitted, equal to the intensity in candelas multiplied by the solid angle in steradians (1-(4·pi) of a sphere) into which the light is emitted.
Source: http:--www.onlineconversion.com-faq_10.htm (Russ Rowlett at unc.edu)
Read less
***
Some light sources are rated in various different units, such as *candlepower or watts. To be able to compare different types of light sources, it would be necessary to convert between these types of units.
The short answer is, you cannot. Unless the manufacturer already has calculated both candlepower and watts, you're pretty much out of luck. However, here are some units, and quite unrelated to birthdays!
- candlepower
One candlepower is the radiating power of a light with the intensity of one candle. Replaced by the candela in 1948, it is still in common use. 1 candlepower is equal to about 0.981 candela.
- candela
The standard unit for measuring the intensity of light. The candela is defined to be the luminous intensity of a light source producing single-frequency light at a frequency of 540 terahertz (THz) with a power of 1-683 watt per steradian, or 18.3988 milliwatts over a complete sphere centered at the light source.
- lumen
The standard unit for measuring the flux of a light being produced by a light source. One lumen represents the total flux of light emitted, equal to the intensity in candelas multiplied by the solid angle in steradians (1-(4·pi) of a sphere) into which the light is emitted.
Source: http:--www.onlineconversion.com-faq_10.htm (Russ Rowlett at unc.edu)
Read less
Views
180
Likes
Categories
Same photographer See all
Discover more photos See all