Noise reduction is one of the most crucial aspects of professional picture editing. This technique is widely employed in postproduction for eliminating any traces of digital noise from the image.
Noise is an unavoidable aspect of digital photography and is present even in the output of most modern cameras available in the market. Noises are slight abnormalities seen in the image particularly in the area of high or low brightness. They are generated due to many of the slight faults that occur while capturing the image such as exposure, aperture, ISO, and shutter speed.
Most of the cameras allow the photographer to adjust the ISO settings up to certain limits. However, in low-lit conditions, the need of adjusting the ISO settings to larger values will compromise the set limits, thereby allowing digital noise to form in various portions of the image.
Modern cameras also come equipped with many inbuilt tools to reduce noise in the images during capture. However, these are not effective in fully eliminating noise from the image and require advanced post processing techniques in completely removing them.
Luminance And Chromatic Noise
In digital photography, there are two types of noise: luminance and chromatic. Luminance noise is directly linked to the lighting conditions and the lack of proper illumination during the capture of the image. Luminance noise is colorless in appearance and differs according to the pixel size of the image sensor, the size of the sensor and the ISO value used. Higher ISO values generally mean that the individual pixels are enhanced thereby increasing the intensity of the signal generated by each pixel.
Chromatic or color noise is variations in the color tones among the individual pixels. This noise usually occurs in dark or light portions of the images and causes the introduction of additional color information in the image. Chromatic noise can cause more disruptions to the image than luminance noise and can affect the appearance of the whole image.
Noise reduction is widely employed by most photo editing services for virtually eliminating any traces of both luminance and chromatic noise from the image. The advanced imaging software used in professional picture editing can decolorize the individual pixels that can effectively help in tackling noise in the image. Photo editing is the effective way to deal with digital noise in the image, as the in-camera settings available in the camera are not capable of handling them.