What is Crop Factor?

Learning different techniques and types of photography is important. But another equally important thing is learning the technical aspects of your equipment. In this guide, we are going to discuss one of the aspects which not only confuse beginners but some experienced photographers as well. Get ready to know what is crop factor and when you should prefer crop sensor or full-frame. 

Read along to understand more about it.

Understanding Crop Factor

Before moving on to the lens crop factor, it is important to understand the background behind it. If you are familiar with 35mm film, you would know that it did not matter even if you used a 50mm lens. The reason behind this is that everyone knew the difference so there was no confusion around the whole topic. But as soon as the world shifted to digital cameras, new terms like full-frame and crop sensor came into being. However, you need not worry, we are here to explain all of the technicalities to you. When the shift to digital cameras began, it was observed by manufacturers that it would be impractical to build digital cameras the size of 35mm film. Therefore, smaller bodies were produced for them. You might have guessed, this too started to cause a problem. Now, let’s talk about this problem and understand what is crop factor. A lens projects light onto the camera sensor in the shape of a circle. However, since the sensor is in the form of a rectangle, our images come out as rectangles as well. The problem created was that when smaller sensors were used, they cropped off the parts of the image. This resulted in a smaller image. The effect was called as lens crop factor and the sensors are now called crop sensors. On the other hand, sensors having the same or equivalent size as 35mm are referred to as full-frame.

Equivalent Focal Lengths

Another question that most photographers ask is whether crop sensors affect the focal length of the lens. The lens crop factor and the size of the sensor affect the focal length, so we get a new equivalent focal length for different cameras and lenses. However, the point to understand here is that the focal length of the lens itself, cannot be changed as it is a physical value. The difference that comes in the focal length is due to the reason that the sensor is cropping into the image rather than changing the focal length
Photographing sunset - What is Crop Factor?

Photo edited in Lightroom.

Now, let us see how the lens crop factor brought a change in the lens sizes and camera systems. When the smaller cameras were made, the manufacturers noted that the edges of the image circle were not in use. So, it would be a better choice to make smaller lenses. It would not only reduce the weight of the lens by reducing the glass but would also decrease the price of the lens. This also gave rise to mirrorless cameras which use crop sensors and smaller lenses.

Full-Frame Lenses

Now that you know what is crop factor, you should also know if buying a full-frame lens would benefit you. The first thing to understand here is that most of the professional cameras, even the APS-C bodies, are compatible with full-frame lenses. It alone gives you more reason to buy a full-frame lens because you can easily shift between APS-C and a full-frame sensor. It would also be better to get a full-frame lens if you were planning to shift from APS-C to full-frame. Many lenses are made specifically for crop sensors. However, unless they have a compatible mount, they cannot work with a full-frame camera. Therefore, the simple idea is that full-frame lenses are wider and more future-friendly than crop sensor lenses.
Photographer on a lake - What is crop sensor?

Crop Sensor Cameras

The last topic of discussion is knowing the value of crop sensor cameras. The first advantage of these cameras is that you can use both full-frame lenses and crop lenses. The second thing is that the reduced size results in a reduced price. The point that these cameras are compatible with a whole range of lenses makes them more beginner-friendly. If you are thinking about buying a crop sensor camera, it would be better if you paired it with full-frame lenses. This way you would have a safe path if you were ever to shift to a full-frame camera. The only drawback to these cameras is that their ability to handle low-light is slightly inferior. However, you can find some exceptions to this as well.

Conclusion - What is Crop Factor?

Knowing what is crop factor and understanding all its implications will help you choose your cameras and lenses. However, do not let all these technicalities stop you from taking action. Choosing your camera and lens will ultimately depend on your preference and style of photography.

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Have a nice photoshoot! 

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