Camera Sensors: Crop vs Full Frame

For photographers looking to upgrade their camera gear, one of the most important decisions is whether to choose a camera with a crop sensor or a full frame sensor. The sensor size has a significant impact on factors like image quality, depth of field control, low light performance, and more. Here’s a breakdown of the key differences:

Sensor Size

The main distinction lies in the physical dimensions of the image sensor. A full frame sensor is approximately the same size as a single 35mm film frame, measuring 36mm x 24mm. Crop sensors, also known as APS-C sensors, are smaller, with dimensions around 23.6mm x 15.7mm for most brands. The smaller size “crops” or trims the image from what a full frame would capture.

Field of View

Because of the smaller sensor area, crop sensor cameras effectively multiply the lens focal length by a “crop factor.” For most brands this is around 1.5x-1.6x. So a 50mm lens on a crop sensor provides a field of view similar to a 75-80mm lens on a full frame camera. This can be an advantage for subjects like wildlife where you may want more reach. But it also makes it harder to achieve ultra-wide angle perspectives.  

Image Quality

Full frame sensors generally produce better image quality, especially at higher ISOs. Their larger photosites can capture more light, resulting in less noise and greater dynamic range. However, newer crop sensors have significantly narrowed this gap in recent years.

Depth of Field Control

A full frame sensor provides shallower depth of field compared to the same aperture and focal length on a crop sensor. This allows easier separation of subjects from backgrounds with attractively blurred “bokeh” highlights. Crop sensors require wider apertures to achieve an equivalent depth of field.  

Size and Weight 

As a tradeoff for their improved imaging capabilities, full frame cameras and lenses tend to be significantly larger and heavier than crop sensor models. This makes full frame systems less portable and more cumbersome for extended carrying.  

Price

Full frame cameras and compatible lenses demand a premium price due to their enhanced performance and more complex manufacturing. Entry-level and enthusiast photographers often start with more affordable crop sensor options before potentially moving to full frame.

In the end, the choice depends on shooting requirements and budget. Professionals and serious enthusiasts often prefer full frame for the versatility and uncompromised image quality. But crop sensors provide an excellent combination of performance and value, especially as the technology continues advancing.