# How can you increase power of a light source?

I've heard that red light is dimmer compared to green light emitted with same power and to if you want to have same intensity of light you have to crank up power of red light. From equation for power $$P=\frac{W}{t}$$ you can see that to increase power you have to increase energy or decease time, but we can't increase energy because that would change color of the light according to this equation $$E=hf$$. E.g. in red laser, how can you increase power in it to have the same color?

I feel like missing some important information on this topic.

• From the question I have asked a second ago, The brain interprets colour via frequency, The equation E=hf is the energy of an individual photon, increase the number of photons and you have a more intense version of that colour. Dec 4, 2021 at 14:23

EDIT after question edit: Yes, you are definitely missing a big part of the picture. Photon energy ($$E=\hbar \omega$$) has nothing to do with the total amount of energy in a light beam. See this differently, the total energy is equal to the total amount of photons of energy $$E$$. If your source gives off photons of a certain energy, increasing its output power is just increasing the number of photons emitted, not changing their intrinsic frequency.