If photography means “writing with the light”, we can think that light is our ink. But what is being played the role of the pen? and the sheet?
Figuratively speaking, I would say that the pen is the lens through which the light (ink) flows, and the sensor is the sheet on which the light is laid, leaving a trace.
In this metaphor, the exposure is nothing more than the amount of ink being spilled on the paper. Too much ink “burns” the paper and will not allow us to read anything, too little produces an opposite effect, but no better.
If we think about it, there are 3 parameters that we can control to determine the correct amount of ink:
For photography, there are exactly the same parameters and they are called:
From next post, I will start talking about the shutter speed.