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Size does matter when it comes to Camera Sensors!

Are you confused with what APS-C and Full-frame sensor actually mean? Do you wonder what are the differences? Well, we’ve all been there. But hang around to the end of this article, and I will make sure you have a decent understanding of all the significations of different sensor sizes and why it is important for you to know about sensors. By the end of this article, you will have enough knowledge of the types of camera sensors and you will know the right sensor size for you.

Different Sensor Sizes and What They Do

Before we jump into technicality, what is a camera sensor? In layman terms, it is simply like a single exposure from a film that can be used indefinitely. In the pre-digital camera days, films came in different sizes. Similarly, now digital cameras come with sensors of different sizes. In digital cameras of this age, the sensor basically absorbs the light to create an image. If your camera has a larger sensor, then the sensor will absorb more light, resulting in better image quality.

There are so many manufacturers out there and even more camera models. But lucky for you, camera sensor sizes are standardized, which means you do not need to know about a thousand different sensors.

The most common camera sensor sizes are highlighted here:

  • Full-frame: A camera (with a full frame) sensor is measured to be 36 x 24 mm approximately. It is based on legacy 35mm films of the old days. These sensors are often found in pro-level DSLRs and mirrorless cameras.
  • APS-C: APS-C sensors measure around 22 x 15 mm. It has a crop factor of 1.5 times, meaning that since the sensor size is smaller than that of a full-frame sensor, the image is cropped in closer, about 1.5 times than what you would get on a full-frame sensor camera. APS-C sensors are typically seen in most entry-level and mid-level DSLRs. A few high-end compact cameras also have APS-C sensors. Interestingly, some mirrorless cameras by Fujifilm also have APS-C sensors.
  • Micro Four Thirds: Micro Four Thirds sensors were launched with the start of mirrorless cameras. It is the right blend of the right camera size while having good image quality. It measures around 17.3 x 13 mm. The crop factor for Micro Four Third sensors is 2 times. These sensors are mostly seen in Olympus and Panasonic mirrorless cameras.
  • One inch: One inch sensors are mainly designed for compact cameras. It measures around 13.2 mm x 8.8 mm. With a crop factor of 2.7 times, these sensors are found in high-end compact cameras. The quality of these sensors is between that of a beginner compact camera and a DSLR.
  • Compact camera and smartphone sensor sizes: Typical compact cameras and smartphone cameras have varying sizes of sensors in them. They are very small compared to a full-frame sensor. Two of the most popular sizes are a 1 /2.3 inch and a 1 /1.7 inch.

As already stated, the larger sensor size usually means better photo quality, and large sensor sizes make the best cameras.

Usefulness of a camera with large sensors

Better Image Quality

Although image quality is based on a lot of factors like the number of megapixels, the camera’s processer (the brain of the camera), the design of the camera sensor, etc., the most important contributing factor is obviously the sensor size. Having a large sensor in a camera produces images with more light, more details, background blur, and less noise. You can test it out for yourself by taking the same image with two different cameras and two different sensor sizes. You will notice that the camera with the larger sensor produces a better image.

Gathers More Light

The main reason for better image quality is that larger sensors absorb more light. Larger sensors have a larger surface area which means more light can accumulate in a single image. This makes cameras with larger sensors better for low light photography. With the same settings for shutter speed and aperture, a camera with a larger sensor will let in more light. This is particularly useful when you are shooting a night landscape, theatre production, concert, or any dark places.

Handles High Megapixels with Less Noise

Usually higher megapixels are seen with cameras with larger sensor sizes. As an example, a 50-megapixel full-frame sensor camera will have larger pixels than that of a 50-megapixel APS-C sensor camera. Each of the megapixels will have more space than that of the smaller sensor. The main benefit of this is that you get an image with more details. On the contrary, a high megapixel count on a smaller sensor camera shows issues when capturing images in low-light environments. The smaller sensor cameras will have more noise in the images.

Creates More Background Blur

It is near impossible to get that beautiful bokeh effect in cameras with a smaller sensor size. This is why I personally do not like using the portrait mode in smartphone cameras. The background blur effect in smartphones is created with software and not natural. The sensor size in the smartphone and compact cameras are too small to create a real effect. This is why you should get a camera with a larger sensor size if you want a background blur effect in your photos. The larger sensor size has an enlargement factor working for it that increases the background blur. Moreover, since a full-frame sensor has no crop factor, you will tend to get closer to your subject which will also help you in getting that desired bokeh effect.

Benefits of having a smaller sensor camera

Although I have only talked about the benefits of a larger sensor camera so far and you may be wondering why smaller sensors even exist, they do have some benefits.

Allows for Better Zooms

The first benefit of using a camera with a smaller sensor size is its capacity for better zoom. Due to the crop factor in cameras with a smaller sensor, it is easy to get close to the subject through the lens. Additionally, zoom lenses that are designed for sensors smaller than a full-frame are generally cheaper and smaller in size. Let us consider a Micro Four Thirds sensor camera. It has a crop factor of 2 times. This means if you are using a lens of 300mm focal length, you are actually seeing objects at a 600mm focal length distance. This advantage of not having to move close to the subject is really useful in wildlife and sports photography.

Smaller Size of Cameras

It’s probably a no brainer that a camera with a smaller sensor size will be a smaller camera. Now before you start bashing on me saying that there are Micro Four Thirds like the Olympus OM-D E-MIX that is not so compact, it’s safe to say that there are exceptions. But in majority cases, smaller sensor cameras are generally more compact than full-frame sensor cameras. They also weigh less than some full frame cameras. If you are looking for a camera to travel around with, you might be inclined towards getting a camera with smaller sensor size as carrying it around will be easier. Moreover, lens sizes are more compact.

Friendlier on the Pockets

The best part of choosing a camera with a smaller sensor size is the price tag. Most full-frame sensor cameras are pro-level cameras, which means that they usually have a huge price tag. Most full-frame sensor cameras start around $1,200 to $1,500, but some cameras go beyond $3,000. In terms of the best value for money cameras, you can go for a camera with an APS-C sensor. These cameras are priced at a few hundred dollars, and you won’t need to spend thousands in one go. The best part is that these cameras have a lot of high-end functionalities without needing to pay a pro-level price.

Which sensor should you choose when you buy a camera?

 It really depends on your priorities and what you want from your camera. There are no right answers here. If you want the best quality images with a lot of background blur effect and the best low-light performance, and you do not mind spending a large sum of money then definitely go for a full-frame sensor camera.

If you do not want to spend thousands of dollars on your very first camera, but you still want a camera with pro-level features, then you should go for an APS-C sensor camera. Also, on the budget side are Micro Four Thirds sensor cameras. These cameras have extended zoom capabilities and are very compact, making it convenient for travel photography.


I have talked about camera sensors so much up until this point that you may think that that is the only important factor for image quality of any camera. However, in reality, there are a number of other factors when it comes to image quality. Megapixels are really important as more megapixels mean more details in the image. The camera’s processor (the brain of the camera) is also largely responsible for image quality. Cameras that have come out in recent times with the latest processors usually produce images with less noise. The lens being used to take the photo is also important. All these factors together work to produce a good quality image. This gives you plenty of reasons to be cautious when you’re buying your set-up.

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