I am frequently asked about how to adjust camera settings to reduce motion blur for photos. In each case I try to learn one thing; “How much light enters the camera lens?”
Let me see if I can bring technical specifics down to a lower altitude for us to work on without the fear of nose bleeds.
Taking photos is not all so different from looking at those beautiful scenes we are so blessed to wander through, savoring the grace and delicacy of the garden. However, I would not deceive you, there are some very specific differences between our Eye, Optic Nerves and Brains as compared to camera lenses, censors and processors.
Let me start this post set with a discussion on the make-up and structure of our vision.
Our Eye takes in a lot of information, filtering it through a complex network of cones, rods, blood vessel and finally to an Optic Nerve situated at the back of the Eyeball. This only begins the wondrous process we call “sight”.
As the Optic Nerve receives the information from the Eye, it begins informing the Brain through neurological pulses. The brain then both processes and stores the information.
So, to simplify that chain process down to a basic form is this: Eye to Optical nerve to Brain.
Now, please stay with me, we will be looking at some details within the eye that will later be applicable to cameras.
The Eye is very complex and since I am not an Optometrist I will not pretend to know every detail. The basics we will benefit in knowing are these:
- The Eye Lid, protects from injury, cleans the Eye of debris and is a front line defense to direct sunlight.
- The lens of the Eye is called the “Cornea”. It slightly changes shape, with the aid of muscles behind the Eye Lid, to form the properly curved angle for the purpose of focusing on objects near or far.
- Underneath the Cornea are the Pupil and Iris. It is very easy to start talking about both the human Eye and cameras right now, but I choose to remain on optic…I mean, topic. The Iris is the colored “ring” and the part of the Eye from which we discern the “Eye color”. It contains at-least one muscle which constricts the inner opening of the Eye (the Pupil) when you step out-of-doors and into the sun. The muscle or muscles will also relax and the Iris opens allowing the Eye to receive more light.
- I just made a statement about the Eye receiving more light, which in a manner of speaking is true. However, there is a part of the Eye called the “Retina” which is the specific receptacle of light. The Retina is very sensitive to light and will easily burn if not protected by the Eye Lid and Iris.
- The Optic Nerve is next in process from the Retina, sending the neurological pulses received from the Retina to the Brain.
- The Brain receives the neurological pulses from the Optic Nerve and catalogs those pulses in its own magnificent way.
This article is already pretty long, so I will bring it to a close and bring you “Part 2” on Friday. Before we close though I would like to bring out one last thought.
When you step into a dark area from a well-lit place, it takes your eyes a measure of time to adjust. For some people their eyes adjust faster than others while others employ methods which seem to speed the process along. One way I have heard effective is closing the Eye Lid during the transition.
Have you noticed in a low light situation, quick or faster motions do not seem as smooth or connected? At the very least in low light situations quick or faster motions are more easily concealed.
I hope this Friday to make the mystery of the “pesky camera” plain.