Human eyes and the tools we use to make photographs, cameras and lenses have some similarities.
As photographers, keeping these similarities in mind
might help us understand what we do with our camera to focus and control tonality (the brightness of our photograph).
We can think of the retina at the back of our eye, similar to the digital sensor, or film, in the back of our
cameras.
Our Eye and Camera Lenses Can Focus
The human eye is a
lens that focuses light onto the retina.
The lens on our camera focuses light onto a digital sensor.
The human eye focuses, and photographers use a camera lens to focus.
The result is making
things at a specific distance appear sharp.
Our Eye and Camera Lenses Can Change the Size of Their Openings.
The human eye is a lens that allows a retina to be exposed to more or less light with a pupil.
And the lens on our camera allows a digital sensor or film to be exposed to more or less light
with an aperture(f-stop).
The iris in our eye controls our pupil size.
And we, or the camera, control the aperture size.
A bigger or smaller pupil opening allows more or less light to affect our
retina.
And a bigger or smaller aperture opening allows more or less light to affect our digital sensor or film.
Our pupil gets bigger or smaller in response to darker and brighter light.
And we,
or our camera, can make our aperture bigger or smaller in response to darker and brighter light.
By changing size, our pupil changes how much light (exposure) reaches our retina.
And by changing size, our aperture changes how much light (exposure) reaches our digital sensor or film.
More exposure to our retina, digital sensor, or film makes things appear brighter.
And less exposure to our retina, digital sensor, or film makes things appear
darker.
There’s a Significant Difference Between Our Eyes and Our Camera Equipment
Even though there's similarities between our eyes and camera equipment, there's a significant difference.
The difference is that we don't need to know how to work our eyes to see images.
The images are seen automatically.
But we need to know how to work our camera to create and see the images we call photographs.
If you need some help with that, especially if you've got a DSLR or mirrorless camera, keep
scrolling to see ways to learn photography with me.
