Cameras have steadily grown smaller over the years with the exception of a few. RED’s cameras have shown us we can get 4K from a camera half the size of an original film camera. Black magic’s 2K “pocket camera” is just that, small enough to put in your pocket. GoPro boasts a 2K image, and you are able to pick up an iPhone with 1080P capabilities. There are differences to these cameras though. If you look closely at GoPro’s and iPhone’s images, you’ll see they pale in comparison to the more expensive cameras. Why is this? The answer (or part of it anyways) is in the glass.
How does our world get focused onto that little image sensor? Through the lens you put in front of it. The quality and size of the glass on your camera greatly influences the quality of image your camera can capture. The quality of the glass affects the color range and sharpness of your image. The more pieces of glass you have in front of the camera, the harder this becomes. That is why primes (or fixed focal lengths) are usually sharper and more vivid.
The size of glass also depicts the amount of light able to be captured. Light waves do not shrink with time. To capture as much of this light a larger lens will logically do better. So let’s look back at the GoPro and iPhone. What kind of glass do these have? Yes, they have a fixed focal length, but they are also of lesser quality and tiny in comparison to a normal sized lens. This tells us these cameras will receive less of a much poorer quality light to their sensors.
So remember, It’s bright, to choose your lens right, and capture that light!