With analog photography, the film you choose is the recording medium. With digital photography, a digital sensor captures and records the light. Your choice of sensor will determine the quality and resolution of the resulting digital image.
Better sensors come at a bigger price, but what makes any one sensor better than the others? Do you need the biggest sensor possible? We have the answers to your questions below.
What is a Digital Photography Sensor?
A digital photography sensor is how a digital camera records any given scene. Unlike 35 mm film photography, you aren’t able to change the sensor your camera uses, which makes your choice in camera very important.
The sensor is a chip that records the light in the scene you are capturing. The chip contains millions of photosites/pixels (photodiode with light sensitive crystal silicon) that converts the light into an electrical charge. This recorded light (saved as an analog electric signal) is then amplified and sent to an Analog to Digital Converter, recorded as a number. These numbers let our computers know the location and brightness of each pixel.
Only a certain size of the chip is light sensitive. Around 30 to 40% of the chip contains the photodiode that records the light. The rest of the chip holds circuits for noise reduction and amplification. To increase the light hitting these diodes, manufacturers use Micro-lenses. These redirect the light that would otherwise fall on areas that are not light sensitive.
Do Digital Cameras only Have one Sensor?
Some have more - SLRs and DSLRs can have a sensor for focusing alongside the sensor for capturing. A Phase Detect autofocus sensor allows the camera to use both autofocus models (phase detect and contrast detect).
Are there Different Types of Digital Sensors?
There are two different digital sensors; CCD (Charged-Coupled Device) and CMOS (complementary metal–oxide–semiconductor). Both capture light and convert them into electrical signals. What makes them different is the fabrication and cost. CMOS sensors are more expensive and found in high-end digital cameras.
What Makes a Digital Sensor Better than Others?
A digital sensor is how a digital camera records any given scene. Unlike 35 mm film photography, you aren’t able to change the sensor your camera uses, which makes your choice in camera very important.
The sensor is a chip that records the light in the scene you are capturing. The chip contains millions of photosites/pixels (photodiode with light sensitive crystal silicon) that converts the light into an electrical charge. This recorded light (saved as an analog electric signal) is then amplified and sent to an Analog to Digital Converter, recorded as a number. These numbers let our computers know the location and brightness of each pixel.
Only a certain size of the chip is light sensitive. Around 30 to 40% of the chip contains the photodiode that records the light. The rest of the chip holds circuits for noise reduction and amplification. To increase the light hitting these diodes, manufacturers use Micro-lenses. These redirect the light that would otherwise fall on areas that are not light sensitive.
How is Sensor Quality Recorded?
When the first digital sensor in 1975, held 0.01 megapixels (1000 photosites). Currently, you can buy a medium format digital camera that holds a sensor of 100 megapixels (100,000,000 photosites). The amount of megapixels does denote the quality and detail you can take from each scene, but they are not the be-all-and-end-all.
Sensor size plays a big role, for example, a full frame 35mm DSLR camera will outperform a smaller sensor (APC-S) when both hold the same megapixels.