Photography - Gear/Equipment

Optical Zoom vs Digital Zoom: Know the Difference

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With all those high-tech cameras available in the market, choosing the right one for ourselves is not an easy task. There is so much technical jargon being advertised that we end up unsure of what to purchase. One such term is the zoom. All cameras specify their zoom capacity on their boxes. However, most of the time, this value is the total of their optical and digital zoom. Therefore, it is important to understand optical zoom vs digital zoom before making a purchase.

Most camera manufacturers try to boast of very high zoom values. In reality, however, this is misleading and the choice of a camera should never be based on a higher zoom. This is because the manufacturers tend to highlight the total zoom, i.e. optical zoom and digital zoom values added together. In the following sections, we will see why this is a completely wrong way to calculate zoom.

Optical zoom vs Digital Zoom: Understanding the Difference

What is optical zoom? It is the feature of the lens that allows you to take a closer shot of the subject without the photographer actually moving. The optical definition of zoom depicts the ability of a lens to magnify the object. Digital zoom, on the other hand, is the ability of the camera to crop the image and enlarge it. Because the digital zoom alters the image after it has been captured, it is very similar to the processing that can be done in any image software like Photoshop. This means that digital zoom is not really a feature that is inherent to the camera.

So, when comparing two or more cameras, the optic definition of zoom holds more value for picture quality. In fact, the term ‘digital zoom’ is misguiding because there is no zoom of the picture here. The image is just cropped up and enlarged, thereby giving a lesser resolution. In other words, there is no comparison of an optical zoom vs digital zoom because digital zoom is a software-based modification of the image.

Optical vs. Digital Zoom: Understanding the Difference
Optical vs. Digital Zoom- Understanding the Difference(Source)

Effect of Optical and Digital Zoom on Image Resolution

If you have understood the basic difference between optical zoom and digital zoom, you will be able to predict the effect of these two on the image resolution. While the image quality is not altered at all when the zoom is optical, digital zoom leads to lowering the image resolution and making it more pixelated. Hence, the image resolution is a key difference in optical zoom vs digital zoom comparison.

Every time you adjust the camera’s optical set-up for zooming, the lens and other parts in the camera physically adjust and give you an image. Therefore, the quality of the image is not altered. This means that optical zoom will adjust image quality before capturing the image. Digital zooming simply takes the captured image and crops it up to enlarge it, drastically lowering its resolution in the process. In other words, the optical zoom will never be related to the megapixel resolution of the camera model.

Optical and Digital Zoom
Zoom effect on Image Resolution

Digital Zoom as Smart/ Safe/ Intelligent Zoom

Most people understand that digital zooming is practically useless because all these alterations can be done with optical zooming during image processing. Hence, camera manufacturers have come up with the concept of smart zoom / safe zoom and intelligent zoom. These are all modifications of digital zoom and allow the user to compromise much lesser on image resolution.

In this feature, the camera gives the user options to save the image in a smaller than the maximum size and trims away the pixels at the periphery of the image. This way, the image quality is not so drastically lowered, and the image gives an enlarged look.

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Optical Zoom vs Digital Zoom: Uses of Each

Optical zoom is an excellent way to capture an image with the intention of taking a closer view of the subject. It also serves well in landscape photography where the minor attributes of the subject are vital. Digital zoom is best used for cropping out selected sections of the image after the image has been captured.

Optical Zoom vs Digital Zoom: Zoom Factor

Let us understand the concept of zoom factor of a zoom camera. In general, the digital zoom of cameras is a high number, for example, above 700x. This simply means that the camera is capable of enlarging the image over 700 times. For most common applications, a digital zoom of 4x is more than sufficient. 4x digital zoom means an enlargement of the image four times, and this itself leads to a lowering of resolution. Now imagine what will a digital zoom of 700x do to your image.

Now consider the optical zoom of the camera. The maximum zoom, in this case, will be 25x. But this magnification of the image will not give you any blurring, pixelation or decrease in resolution. Therefore, it is not prudent to go for a higher number associated with the zoom. The best zoom camera will be the one with a higher optical zoom, and a digital zoom is just a number.

Read: Understanding Lens Calibration: A Fix to Blurry Photography

Advantages of a Higher Optical Zoom

There are clear advantages of having a higher optical zoom in your camera. These advantages make it important for you to choose a camera that has a higher optical zoom.

  • There will be no loss of picture quality when you zoom in using the optical apparatus. This gives you the scope of clicking pictures with more details, vibrant colors and fine aspects highlighted.
  • The optical zoom of your camera will never be dependent on the megapixels.
  • With a higher optical zoom, you will be able to take clear pictures from a farther distance.

Despite the marketing gimmick by most camera companies, the informed user should be aware of the differences between optical and digital zoom. If the users understand the importance of optical zoom for image quality, it will be easier for them to choose the right camera for their purpose.

Read: Lenses for Beginner's Photography kit

We hope that by means of this article, we were able to unmask the differences between the two kinds of zoom. Now that you know the clear winner in the optical v/s digital zoom comparison, let us know how the two kinds of zoom work for your image.

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