Sensors: Which One is Right for You?
Sensors can be confusing. Certainly the names don’t help. While knowing the acronyms might not be terribly important if you’re looking to buy, you should keep in mind that in terms camera tech, bigger isn’t always better. Here are some guides that you might find useful when considering your first camera, or an upgrade.
Individually, sensor size is often dictated by camera size. The Micro Four Thirds System found in mirrorless interchangeable lens digital cameras is the same size as the Four Thirds System found in some DSLRs, establishing it at the lower end of the larger sensors. Smaller sensors can then be generally found in compact point and shoot cameras, or even most bridge cameras.
Individual sensor sizes.
Comparison of Sizes and Applications
Sensors in relation to one another.
Not everyone is going to need (or want) a full frame. Many photographers swear by the performance of the Fourth Thirds sensor. But does that mean that a smaller sensor is better? In general, smaller means noisier. If your sensor is 1/3.2″, it’s going to have more noise at ISO 800 than if it was full frame. However, smaller areas are easier to keep cool, so if you shoot a burst of images, there will be less noise from sensor heat if you’re using Four Thirds instead of the APS-C. Smaller sensors also require smaller (and usually lighter) lenses, making portability much easier. If you’re hiking around taking photographs of wildlife or landscapes, and don’t have much need for high ISO or shooting in high bursts, small is okay.
If you’re shooting street photography at night, odds are you would be better off going with a camera that won’t show as much noise at higher ISO.
Another thing to keep in mind when considering sensor sizes is your intended medium for showing your photography. The larger you want your finished image to be – whether it’s a 18×36″ print or a profile picture for Facebook – the larger you want your sensor to be. For years I worked with Nikon’s APS-C sensor and loved it. I have printed my photos at anywhere from 4×6″ to 24×36″ for shows and personal use, and everything looked hunky-dory, even at the larger size, with no pixelation whatsoever. If you simply want to show some photos online, you don’t need a full frame camera. Heck, you don’t even need a ton of megapixels (but that’s another story).
Angle of View and Crop Factor
Brackets showing effective crop factors.
So what then is the oft-mentioned Crop Factor? Crop Factor is a number arrived at by comparing the diagonal of a sensor to the 35 mm (or full frame) standard. Smaller sensors mean higher crop factors, and higher crop factors in turn mean greater image loss. Loss occurs at the outer edges of the image, and effectively cuts down on field of view. From this decreased field of view comes the idea of a comparative focal length, e.g. a smaller sensor with a 1.5x crop factor paired with a 50mm has a comparative focal length of 75mm. So, if you use a lot of telephoto lenses, a cropped sensor is good, but if you have more wide angle lenses in your arsenal, consider the full frame.
Want to know more? Check out this article.