What is Resolution on Digital Cameras?

What is the resolution of the best digital cameras? It is the size of the image that a camera produces in megapixels. If the digital image recording is on film, the resolution will depend on the image file size, average photo size, lens sharpness, grain levels, and diffraction. If you are using a camera with an image sensor, the factors that determine resolution include pixel pitch, ISO, diffraction, AV mode, the size of the sensor, and lens sharpness. Additionally, the condition of the equipment, atmospheric blur, motion blur, focus, and camera shake influence the clarity of the image.

Let us discuss two of these elements in detail.

Important Factors Affecting the Resolution of Your Digital Camera

Pixel Size and Pixel Pitch

Smaller pixels require a better lens quality. For example, an eight-micrometer pixel has twice the pixel pitch of a four-micrometer pixel and four times the area. This result means that with a lens that provides sharp details for the eight-micrometer pixels, it is not possible to offer enough sharpness for the four-micrometer pixels. So, there are two places where you can get small pixels:

• Smaller image sensors with standard pixel count: the 12MP camera of an iPhone XR has a small sensor with pixels that only measure 1.3-micrometers. Therefore, its pixels are 9X smaller than those of a 5Ds R’s pixels. Suppose an original Canon 5D has a 12 MP pixel count on a full-frame sensor with an eight-micrometer pixel pitch. Then its pixels will be 36 times larger than those of the iPhone XR. 
• Large image sensors with high pixel count: a Canon 5Ds R with a four-micrometer pixel pitch is a 51MP full-frame camera. When you have small pixels, you get more diffractions which you can notice at low apertures. E.g., f/2.8. So, what is diffraction?

What You Need to Know About Diffraction

 You may remember diffraction in water. If there is a barrier with a small hole to allow water, the flow will bend near the hole. A smaller hole means more bending. The same concept is similar in photography, where the camera aperture is the hole that allows light. At higher f-stops (smaller apertures), diffraction affects your resolution and image sharpness. Just because of diffraction, there is a physical limit on resolution.

How Lens Sharpness Impacts Resolution

You can see the resolution of a lens irrespective of pixel count and sensor size on MTF charts. But you can also look at your lenses to see if they are sharp enough for your shoots. Pixel-level sharpness is the highest degree of lens sharpness, which means that a sharp lens can resolve image data at the pixel level without interfering with the neighboring pixel. This sharpness depends on the lens and the pixel pitch of the cameras.

How to Get the Highest Resolution

You do not have to go out and purchase a camera with the highest megapixel camera. Pixel count and megapixel mean nothing without the right technique and settings. Remember that your goal is not to record the greatest detail of an object. Do not be obsessed with sharpness because photography is all about storytelling and technique. You should also be aware of what is RAW images on a digital camera as it affects image size and quality.

Let’s begin with the different ways you can achieve the highest resolution.

• Understand your lens: know the weaknesses and strengths of your lens. Then, determine the apertures that work best. Next, check which close-up focus results in a blurry image. Lastly, throughout your zoom range, check the sharpness at different focal lengths.
• Get familiar with your camera: know the ISO levels you can use without compromising your image.
• Set it up properly: set it to the best JPG quality and full aspect ratio. Alternatively, you can go for RAW to get creative in post-production. Also, check the sharpening settings of your camera to emphasize the details of an image. But when you over-sharpen, you will damage the image details.
• Use the right shutter speed: test shutter speeds across several focal lengths.  
• Check your filters: if you use filters, ensure that they are not downgrading the quality of your image because some cheap filters do so.  
• Clean your lens and cameras: have a proper program for cleaning your lenses and camera before and after shots.
• Focus with precision: exercise how to autofocus so that you can make some minimal adjustments in your AF. For example, recognize when your focus shifts in your lens and then adjust it. Also, manual focus when shooting steady subjects using a tripod. This is why you should know what is self-timer on a digital camera, and how you can use the timer in your camera.
• Check external forces: although dark cloudy days offer photographers lots of creative latitudes, they heavily affect sharpness.
• Check for diffraction: check your pixel pitch and avoid using apertures that tend to be affected by diffraction.

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