What does the sensor in a digital camera do? The camera sensor in a digital camera determines the image size, low-light performance, resolution, dynamic range, depth of field, and even the camera’s physical size. An image sensor is a hardware component in the camera that receives light and converts the subject into an image. Professional photographers choose the best digital cameras with an understanding of the type of electronic sensor they need.
KEY TAKEAWAYS:
- A camera sensor is a photosensitive component that generates electrical charges.
- Different photosites collect different electrical charges. Once there is a complete exposure of the photosites, each charge turns into a digital value.
- CMOS sensors can change in light conditions because it alters individual pixels separately, an aspect that is not present in CCD sensors.
How a Camera Sensor Affects Image Size
The camera sensor determines the way your images appear. It also helps you to know how large you can print your image. If you want to record good image quality, look at the pixel size and the number of available light-sensitive photosites. You should also have a clear understanding of what does digital slr camera mean.
Additionally, sensor sizes affect what you see when you look through the viewfinder. Smaller sensors use a crop factor to lenses, recording on a smaller percentage of the scene than what full-frame cameras can do. A good example of a full-frame camera is the traditional 35mm film.
Another way to ensure you take quality photos is knowing what factors affect digital camera photo quality.
Sensor Types
The most popular sensor types are CMOS (Complementary Metal-Oxide-Semiconductor) and CCD (Charged Coupled Device).
CMOS
The current upgrade of CMOS sensors transcends the standard CCD. As a result, a CMOS sensor has more functionalities than a CCD sensor. CMOS sensors need less power, are more efficient, and are high performers in high-speed burst modes.
CCD
For decades, CCDs have been providing superior image quality than CMOS sensors. Other benefits of CCDs include noise control and better dynamic range. Now, because CMOS sensors are available in budget camera models, its simplicity has caused camera manufacturers to go for CMOS options.
Sensor Sizes
Below is a list of camera sensors, beginning with the smallest to the largest sensors.
CX-format (1 inch)
Nikon announced its CX format in 2011, and it is available on the Nikon 1 camera system. In 2012, Sony’s small Cyber-shot DSC-RX100 had a 1-inch sensor with a 2.7x crop factor.
Insider Tip
The camera sensor in a digital camera determines the image size, low-light performance, resolution, dynamic range, depth of field, and even the camera’s physical size. An image sensor is a hardware component in the camera that receives light and converts the subject into an image.
Four Thirds (17.3mm x 13mm)
The approximate size of this sensor is a quarter of a full-frame sensor’s size. In addition, the sensor has a 2x crop factor that doubles the focal length of an attached lens. The Olympus Pen E-PL5 and the new Olympus OM-D-EM1 are examples of cameras with this lens.
APS-C (23.6mm x 15.8mm)
Most DSLR enthusiasts from Pentax, Sony, Nikon, and Canon, use an APS-C sensor. However, it is also important to note that there are different types of APS-C sensors.
APS-H(28.7mm x 19 mm)
Photographers use this type for both high-quality fixed-lens and interchangeable-lens cameras. The APS-H sensor has a large sensor with a good pixel count to boost ISO performance and speed. The sensor also has a 1.3x crop factor.
Full-frame (36mm x 24mm)
A full-frame is the name for the largest sensor size. Full frame sensors are close to twice the size of an APS-C sensor. Pro-level gear like the Nikon D800 and the Nikon D4 use full-frame sensors that do not have a crop factor. That means that what you see is what you shoot. When you pair large sensors with wide aperture lenses, you can have a super shallow depth of field that is great for macro photography. In summary, a large sensor will translate to a larger camera body and a large lens.
Small Sensors
1/1.7 inch (7.6mm x 5.7mm)
These are among the largest sensors in compact sizes. In addition, they provide larger pixels for better noise control over the point-to-shoot standard options.
1/2.5 inch (5.76mm by 4.29mm)
This small sensor is common in affordable point-and-shoot camera models. Although these sensors are cheap to manufacture, they are noisy. Additionally, you get a low dynamic range. However, the results are still OK in comparison to smartphone cameras. Other variations in this category include the are 1/3.2, 1/2.3, and others. With tiny sensors (1/2.7-inch), it explains why smartphones are competing heavily in this space.
Insider Tip
The current upgrade of CMOS sensors transcends the standard CCD.
F.A.Q.
Can I rely ONLY on self-cleaning sensors?
Technology is not always the best if you want to get a clear camera sensor. For example, current interchangeable lens camera MICLs and DSLRs have self-cleaning sensors that use ultrasonic vibration speeds to clean the sensor when the camera is ON or OFF. Although this feature helps shake off the dust, it is not a complete substitute for manually cleaning the sensor. It is not easy to determine whether a self-cleaning sensor is clean. So, you have to clean it manually once in a while to ensure no dust is present. Some manufacturers usually send their sensors to a service cleaning center, but that is a time-consuming option.
What is a mirrorless camera?
A mirrorless camera is a digital camera without a reflex mirror. Instead, light passes through the lens into the digital sensor, and the image is projected on the camera’s LCD screen. This feature allows you to adjust the settings of the image before taking a shot.
Why should there be no dust on the sensor?
If the sensor is dusty, you will have to edit out the sensor dust in each photo. So, if you are a paid photographer, you always have to keep your camera sensors clean.
Can an FX lens fit on a DX camera body?
Yes. The FX and DX lenses are interchangeable.
STAT: The standard quantum efficiency values for solid-state imagers range between 30% – 60% (source)
REFERENCES:
- https://en.wikipedia.org/wiki/Image_sensor
- https://illumin.usc.edu/the-digital-image-sensor/
- https://www.nrcan.gc.ca/maps-tools-publications/satellite-imagery-air-photos/remote-sensing-tutorials/satellites-sensors/cameras-and-aerial-photography/9351r
- https://www.visiononline.org/userassets/aiauploads/file/cvp_the-fundamentals-of-camera-and-image-sensor-technology_jon-chouinard.pdf
- https://www.dmi.unict.it/battiato/download/DSC1.pdf
