https://www.youtube.com/watch?v=kLyQY_gK42g
Crop Factor
Crop factor is one of the most important factors to think about, especially when buying a lens. Here are the following reasons why it’s important:
Understanding Crop Factor
Crop factor is common is SLR cameras, which use smaller sensors than less-expensive cameras. Most professional cameras have a sensor that is the same size as that of 35 mm film. However, creating this technology is expensive. To fix the problem of price, camera makers started producing small sensors that could use the old and new lenses.
When this happens, it leads to a crop factor. The reason for this is that you will be cropping the image. It is like printing a photo but on a smaller piece of paper. That means you have to cut out bits to make the image fit.
How much is cropped?
When you use a 50 mm lens that is meant for a full frame camera on a crop sensor, the focal length changes to 80 mm instead of 75 mm. This should not make a big difference. However, you have to know which sensor is on your camera so that you can work out the crop factor.
How to tell if you are using a Crop Sensor
The answer to that question is quite simple. If you buy a camera body brand for less than $2000, you are using a crop sensor. Full frame cameras cost way above that. Besides that, you can check the kit lens that comes with your camera. The focal length will be at 18mm rather than 24mm as with a full frame sensor.
Why Go for a Full Frame Lens
The lenses designed for full frame lenses are usually of a better quality. You can still find nice lenses for crop sensor cameras but they do not come close to the quality of full frame lenses.
Choosing the Right Lens
If you plan to replace the kit lens and you do not plan to upgrade the body for some years, always purchase a crop sensor lens.