Which is Better: Human Eye or Camera?

Which is Better: Your Eyes or Your Camera?

Have you ever came home from a shoot uploaded your photos from your camera and then thought: 

“Wow, this isn’t how I remember the scene at all!”

 Well, there are a few reasons for that. 

In certain ways, your eyes work in the same way that your camera lens and aperture work together. But your eyes are much more sophisticated than a camera, because they have the processing power of your brain behind them.  

So let’s take a simplified look at the similarities and differences between how your eyes and a camera. 

Do Your Eyes Work the Same Way a Camera Does?

Eyes and cameras both have lenses to focus light, and sensors to capture it and produce an image. A camera lens has an aperture that closes down and opens up, depending on the brightness of the lighting conditions. The iris of your eye does basically the same thing, opening up wider, and getting smaller in response to low-light or brightness.  

Both your camera’s lens and your eyes view things upside down because of refraction. 

Refraction is the change in speed when a wave moves from one medium to another. When light moves through your camera’s lens, it causes refraction. The same thing happens when light hits your eyes.

Refraction also causes images to seem to be upside down from what they are in reality. 

Here’s a great example  – how light passing through a glass of water turns an image upside down:

Image Refracting Through Water

When the image from your lens hits your camera’s mirror (or mirrorless camera’s firmware) it flips the image right way up for the sensor to record it.

The image that hits your retina is also upside down, because of the retina’s convex shape.  Via the optic nerve, your brain takes the data it receives through the retina, and flips it the right way again. 

While the basic functions of an eye and a camera with a lens on are similar, there are plenty of differences. Cameras are sophisticated pieces of technology, but they can’t hold a candle to your eyes. 

Photoreceptors: Camera vs. Eyes​

There are vast differences between our eyes and a camera, starting with how they perceive and record light. 

A camera’s sensor (the part of the camera sensitive to light) has a single type of photoreceptors evenly distributed on its surface. On top of the sensor, there are layers of red, green and blue filters stacked on top of the photoreceptors. These filters register short, medium, and long wavelengths of light.

Your eyes’ retinas have unique types of photoreceptors – some register wavelengths of light, while others record the amount of contrast in a scene. We know these photoreceptor cells as cones and rods.

The 120 million cone cells in your eyes register short, medium and long wavelengths of light. (The length of these wavelengths determine the colors we see.) 

Your eyes also have 6 million rod cells that activate in low-light. They do not perceive colour, only varying amounts of contrast. That’s why you can’t see the colors of otherwise identical objects in the dark, although you can make out their shape. 

There are also photoreceptor cells called intrinsically photosensitive retinal ganglion cells. These cells do not contribute to your vision. Their purpose is to help regular your body’s circadian rhythms, and the pupillary reflex.

Another difference between your eye and your camera’s sensor is the arrangement of their respective photoreceptors.  Most of your eyes’ photoreceptors are in a cluster at the center of your retina. The area that doesn’t contain any rods or cones is known as your blind spot. 

You can see this in the image below:

Density of Rods & Cones in the Eye

The cones at the edges of your retina actual purpose is to detect motion, not light. (That’s why you turn your head when you detect motion – so you can focus on it properly.) 

Since we’re talking about focus, let’s compare how your eyes focus versus how a camera does.

Focus: Eyes vs. Camera

How your eyes focus and your camera does are very different. A camera lens focuses by moving in and out until it locks focus. Your eyes actually change shape when they focus, all thanks to the muscles that surround them. 

That’s why when you squint, your vision becomes sharper. Your eyes have changed shape. 

You can’t notice this happening because so much is going on at the back of your eye where it isn’t visible. 

Cameras can only capture what’s going on in the frame between the time the shutter opens and closes. Yes, modern cameras have continuous autofocus to keep moving subjects in focus, but they still can’t evaluate an entire scene the same way your eyes do.

You might have heard that your eye takes in a similar field of vision as a 50mm lens.

But is it this really true?

50 mm or Fisheye?

You might have heard that your principal area of vision (called ‘the cone of visual attention’) is similar in perspective to a 50mm lens on a full-frame camera, or a 35mm on a crop-sensor camera. Scientists have studied the width of the average person’s cone of visual attention and found it is about 55mm wide. 

But this doesn’t take into account how your eyes scan as you view a scene. 

Your eyes actually work more like a video camera, focusing on different parts of a scene as you scan over it. 

Your focus changes as you view the unique parts of the scene, zooming in-and-out on the objects within the scene. 

So the real perspective your eyes capture is more like a fisheye lens, but without the distortion. 

To get the same kind of effect with a camera, you’d need to stitch together a panorama with focus stacking. So far, there is no camera that can do what your eyes do without combining multiple frames, and multiple focus points in post-production.

And that’s a big reason your camera doesn’t render scenes the way you remember, and sometimes leaves you feeling disappointed with your photos.

Your Brain - The Original Photoshop?

Unlike a camera, your brain actually fills in and filters out a lot of visual information for you. It ignores information it doesn’t feel is important to the overall evaluation of the scene.

That’s why you can take a photo and wonder how you didn’t see the power lines in your frame or that dumpster in the background.  Your camera records what’s there in front of it. Unlike your brain, it doesn’t automatically ignore unwanted elements. 

Thank goodness for editing tools to remove those unwanted objects! 

The last comparison I’m going to make in this post is how many stops of light your eye can detect versus your camera. 

Stops of Light: Camera vs. the Eye

The human eye can see up to 30 stops of light; however, it only takes in about ten stops of light at any given time. 

Even if a manufacturer developed a camera so sensitive that it detects 30 stops of light, it would be a waste. Monitors haven’t caught up yet. Your monitor can only display from 10 to 14 stops of light, so that would render a camera technology that advanced as useless!

So how do you overcome the limitations of your camera? By editing your photos! 

Images the Way You Remember Them

With the limitations of camera technology, we need to edit our photos to recreate a scene exactly the way we remember it. 

In my opinion, every photo should be edited! 

Edited? You'd Better Believe It!

It makes me crazy when I hear people say that editing photos is cheating, and your goal should be to get it perfect in camera. 

Shooting in manual mode will help you get it right in camera. I encourage you to learn how to shoot in manual mode, because it will make a massive difference in the quality of your photos. (And I even have a free workshop to show you how!) 

But even shooting in manual mode isn’t enough to produce an image that looks the same way you remember the scene. 

If you’re shooting in JPG format, your camera makes editing decisions for you. That’s right – it decides how bright or dark your finished photo is, how much contrast it contains, the saturation and vibrancy, etc. 

That’s why I recommend that you not only shoot in manual mode but also in RAW format. (I have a post on the differences between JPG and RAW format here.) 

Photos in RAW format are like the film negatives of the past – they need editing! But that’s a big advantage, not a drawback.  

Editing helps you get the artistic vision you had when you pressed the shutter, and it’s an essential skill to learn as a photographer. 

I’d love to help you get the photos of your dreams. 

Join me for a FREE editing training!

Click the image below to register. 

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