Some of the most frequently asked questions from our readers are around DX and FX format sensors. What is DX and FX? What are their differences? Which one is better and why? If you have similar questions and want to get a clear understanding about these formats and their differences, along with seeing actual image samples from both, this article is for you.
Before diving into sensor formats, it is first important to understand what a sensor is and what it does in a Digital SLR camera. It is easier to understand how sensors work by comparing them with the human eye. The lens in front of the camera essentially functions as the cornea of your eyes, gathering ambient light and passing it to the iris. The iris then expands or shrinks, controlling the amount of light that enters the retina, which functions almost exactly like a camera sensor. The retina is light-sensitive, meaning it can adjust its sensitivity based on the available light. If there is too much light, it decreases its sensitivity, while automatically increasing the sensitivity in a dim environment, so that you could see in both extremely bright and extremely dark conditions. Remember what happens when you come out of a dark place to a very bright, sunny environment and vice-versa? Either your eyes will hurt and everything will seem too bright, or you will have a hard time seeing at all – due to sensitivity of the eyes that have not yet adjusted for the new environment. The sensitivity of your eyes is just like the sensitivity of the sensor, also known as “ISO” in photography. But sensitivity comes at a price – high sensitivity levels ultimately decrease image quality, similar to when you have a hard time seeing in a very dark environment. This degradation of image quality is first visible as “grain” or “noise” in the pictures, followed by loss of detail, sharpness and color in extreme levels of sensitivity. When I say “extreme”, I mean extreme to the digital camera, not human eye. Even with all of the latest advancements in sensor technology, cameras are not even close to seeing the range of light the human eye can see in various environments.


