"If we are going to use high-tech devices for our work and play, we need to know how to take care of them. Those are essential skills."
Excellent description of camera sensors and comparison between DX and FX sensors in Nikon cameras.
The sensitivity of your eyes is just like the sensitivity of the sensor, also known as “ISO” in photography.
But sensitivity comes at a price – high sensitivity levels ultimately decrease image quality
Think of those pixels as buckets that attract light particles – the larger the bucket, the more light particles it can store in a given amount of time. These buckets are known as “photosites” and their size plays a huge role in sensor sensitivity and ability to accurately gather light in various lighting conditions.