Camera & Lens Experiments: Crop Factor

ILLUSTRATING THE CROP FACTOR ON A CROP SENSOR CAMERA VS. A FULL-FRAME CAMERA

When using a crop sensor camera such as the Rebel T2i, the crop factor forces the photographer to crop off a significant amount of the subject when photographing the subject from the same distance, OR to back up in order to get the same amount of the subject in the image frame. (For those new to this, the physical size of the camera sensor is smaller in a crop sensor camera than the 35mm-diagonal size of the sensor in a full-frame camera.) In this case, I had to physically back up 23″ to get the same amount of the model ship in the image frame. A common misconception is that due to the crop factor the image is “zoomed” in which would produce a shallower depth of field (blurred background), but this comparison debunks that theory, because when the photographer has to back up the image will have less compression and therefore a less shallow depth of field/more of the background in focus. You can see in the top and bottom examples that the objects behind the subject are not as blurred in the image shot with the T2i (crop sensor camera) as they are in the image shot with the 5D Mark III (full frame camera). [Click image for larger view]