This post is a part of the series of posts on Photography Basics.
I like to share what I learn. And, photography is one topic that I talk about quite often, these days. Here’s the answer to one question I researched for, recently…
As this skilful artistry of photography evolved after the invention of the camera, for some unknown reason, the 35mm became the standard size for all film cameras. All the film cameras, like the Yashica I used when I was a kid, contained film rolls that sized a picture at 35mm (width) and 24mm (height). And, this trend continued as we moved over from the film cameras to the digital cameras.
Based on the timeline, it is somewhere back in 2002 that the first digital “full frame” cameras were introduced. And, because the Canon’s marketing guys needed everyone to get attracted with a larger sensor on a camera, they chose to refer to it as “full frame.” Although, “full frame” is not technically correct, because there may be a time when a new sensor develops with larger dimensions.
There are different sensor sizes available on different cameras. Some of the commonly used ones, in the descending order of the sizes, are (in WIDTH by HEIGHT):
- 35mm “full frame” format, which contains a 36mm X 24mm sensor
- The “cropped sensor” APS-C size, which contains approximately a 23.5mm X 15.7mm sensor
- Micro Four Thirds, which contain approximately 17mm X 13 mm sensor
What difference does the sensor size make?
The simple answer is: The bigger the sensor, the more light it captures. And, the more light a sensor captures, the better your photograph looks; even in low light. But, just having a bigger sensor does not make either your photographs better or you a better photographer. There will still be the other elements and the skilful artistry that unique to only you.
A full frame sensor gives you about 84° angle of view on a 24mm lens. But, an APS-C sensor will give you about 1.5 times of the same image, and consequently about 63° angle of view on the same lens. This means an additional zoom-in into the subject. Such image sensor sizes are popular amongst the wildlife photographers, who would like to zoom closer to their subjects.
On a micro four third sensor, if the lens is compatible, a 24mm lens will deliver almost twice the zoom. Consequently, the 84° angle of view will look like 42° angle of view, and will produce an output of about 48mm.
Does the sensor size impact Depth of Field?
Yes, it does. The simple rule is: Depth of Field (DOF) is in an inverse proportion to the image sensor size. So, you get a shallower DOF for a larger image sensor.
What are the advantages of a “full frame” sensor?
From what I’ve read, there aren’t any advantages other than the following:
- In comparison to the other, smaller sensor sizes, such as the APS-C, a bigger sensor captures more light. And, more light means more details. However, the image quality is a combination of the sensor size, the pixel count, and the sensor circuitry and image read-out mechanisms.
- We read that DOF is inversely proportional to the sensor size. This means that for a 24mm lens, the DOF will be different for APS-C and full frame cameras.