I am supposed to use an light having the following specs. as described in the below statement.
"A red light, equivalent in its luminescence to a 21 W light bulb is to be used."
On an average how much light does an 21 W light bulb emit (in luminescence)??
I am planning to go with a array of high power LED's as it is more energy efficient.
If its LED what should be the power rating of led to give enough luminescence as described in the above statement.
If not LED is there an better option provided it is economical and energy efficient.