Why Image Sensors Matter

Image Sensor cropping

Ever wonder why the lens of a camera is round but the pictures it takes are rectangular? Pictures are rectangular because the image sensor inside the camera is rectangular. The image sensor is almost literally what is looking at the image you point the camera at. It determines what the camera is going to record each time you press the button.

Depending on what camera you use your image sensor will be a different size. As a Nikon photographer, it was important to understand the difference between an FX and DX camera or lens. FX is Nikon’s full frame camera. In comparison to DX, and FX will have a larger image sensor and therefor capture a larger image. This is why a full frame camera takes in more of the same picture taken with the same focal length lens.

My Nikon D750 has a 36mm x 24mm image sensor giving me a ratio of 3:2 which is important to remember. When you go to print an image, do some math. The ratio of my image sensor, and therefore my picture, is 3:2. So anything I print that isn’t divisible by 3 on the long end AND 2 on the short end in relative increments will have a crop. In other words, I can print in 6×4 or 9×6 because either can be divided by 3 & 2 (basically) without cutting anything off. If I print in 10×6 then the long side of my image increased by more than the short side relative to one another and will result in cropping.

Essentially, the image sensor is the rectangle that reflects what your final product is going to look like. Different image sensors are capable of different things. This is why doing your research is important when buying a camera. Know what image sensor you are looking for to accomplish what you want to accomplish. The image sensor is at the core of the camera and the picture taking process.

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Photo Credit: Photo Seek