eli5 Why are some cameras able to capture color while others are just B&W?



Please explain both film and digital

In: Technology

The camera doesn’t matter with film. If you put in B/W film, you get B/W pictures. If you put in color film, you get color pictures.

For digital cameras, you need 3 times more sensor elements to capture color. That means that if you need things to be super small or work at super low light levels, B/W might be a better solution. Lots of security cameras do this to reduce the storage space needed.

With film, you just put black and white film, or color film into the camera. the physical film is the difference, and the chemicals applied to the film determine what the film is able to capture.

For digital, all digital sensors are black and white sensors. What designers do is they take a black and white pixel, and put a green color filter on top of it. Then, the black and white image it receives has the light frequencies shifted by the filter. Then they take the pixel next to it, and put a blue filter on it. And the next pixel gets a red filter. [They scatter the red, blue, and green color filters out over the whole sensor in a sort of checker-board looking arrangement.](https://upload.wikimedia.org/wikipedia/commons/thumb/3/37/Bayer_pattern_on_sensor.svg/1200px-Bayer_pattern_on_sensor.svg.png)

Then, once you take a photo, the camera groups all the red filtered pixels together, all the blue, and all the green together as well, and you have 3 different black and white images, as each is filtered through a different color of light. They then use complex math to add those images together in a way that converts from black and white data into color data, but knowing how much red, how much blue, and how much green is present in a specific area of the image.

[Here is a Petapixel article about the process that may help to understand](https://petapixel.com/2015/11/23/how-to-make-color-photos-using-only-bw-shots/)