How a Camera Processes Light

The Importance of the Light Spectrum

It may be hard to comprehend, but the world has no color. Color is produced when light is reflected from objects; each color has a unique color spectrum. A camera’s processes these light spectrums creating what our eyes and brain perceive as color. If there is not enough light, then an image will seem dark, or simply lack visibility. Many factors, such as image processors and adequate lighting, influence a clear image with proper contrast and brightness. 

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- First, light is described as the natural agent that stimulates sight and makes things visible. 

- Light reflects off objects, and in return creates a visual spectrum of light.

Today’s Digital Cameras

-A digital camera has an image sensor that coverts light into electrical charges. 

-The image sensors utilized by most digital cameras are charge coupled devices (CCD), or a complementary metal oxide semiconductors (CMOS).

-Both CCD and CMOS image sensors convert light into electrons.

-Those electrons represent an accumulated charge which is converted by the image sensor into a pixel value.

-CCD sensors do this by transporting the charge across the senor chip, which converts the charge at one corner of the array. The charge is then turned into a digital value by measuring the amount of charge at each photosite(a specific number of tiny individual sensors), and then converts  that measurement to binary form.

-CMOS devices use several transistors at each pixel to amplify and move the charge using more traditional wires.

Shutter Speed

One major thing that makes video different from photography I shutter speed. For example, when shooting at 25fps, your shutter speed should be 1/50 of a second. If your camera can shoot at 50 or 60 fps, your shutter speed should be 1/100 or 1/125 of a second. This is important because of the 180-degree rule, which is standard practice when filming to achieve video that contains natural movement.

Main Factors that Influence a Camera’s Image Sensor

- Adequate Lighting

  - The amount of light that is produce by the image’s surrounding is going to influence how easy a camera will be able to process that information.

- F/Stops

  - Most lens are equipped with a f/stops. The f stands for focal length of the lens, the (/) means “divided by,” and the number represents the stop in use.

- ISO

  - ISO stands for the International Organization of Standardization, which standardizes sensitivity ratings for camera sensors.

Inadequate Lighting VS. Adequate Lighting

When a scene has Inadequate lighting, the light does not reflect off objects strong enough to produce enough of the appropriate light spectrum for the camera’s image sensor to process a clear image.

How a F/Stop Influences the Amount of Light Entering the Camera Sensor 

The f-stop setting determines how much light is coming through lens into the camera. The larger the f-stop number, the smaller your aperture will be. A smaller aperture means less light gets into the camera.

How Light is Influenced by a Camera’s ISO Sensitivity

ISO is the light sensitivity of either the film or imaging sensor. When you change the ISO on a digital camera, you’re the sensor is more or lesssensitive to light. 

Conclusion

Overall, digital media platforms are using videos more and more often. Cameras are becoming cheaper and the creative art of cinematography is finding a mainstream purpose. Companies, as well as anyone with an Instagram, Snapchat, or Facebook, use videos to help explain, reinforce, and market themselves. Understanding how a camera processes light and interprets that into images is a significant and essential building block to creating videos that look and feel professional.