![]() ![]() While there are many ways to adjust the perceived brightness of an image, the gamma function has a uniquely valuable property - it enables you to manipulate the proportional brightness of midrange tones while leaving the exposure of the brightest and darkest shades unchanged. For optimal image quality, the camera's gamma curve should ideally be adjusted specifically for each scene. 709 gamma curve for television viewing under subdued room lighting - a standard that is not well-optimized for image capture, particularly not for high-contrast lighting situations. The core mathematical formula used in this conversion is known as the video gamma curve, and it determines the relative brightness of dark and midrange tones compared to the highlights. 709 video data and compress the scene's dynamic range into a format designed for viewing on consumer televisions. ![]() ![]() When recording video, Nikon cameras convert the RAW sensor data into Rec. What is actually needed in these cases are controls that enable the user to set not only the exposure level of the highlights, but to independently control exposure of darker areas as well. Unfortunately, the darkest areas in videos compressed with 8-bit H.264 encoders are recorded with noticeably degraded image quality, and this imposes a practical limit on the amount of enhancement that can be applied in post-production. This can result in starkly-lit video images that require significant grading to boost the visibility of shadow details. In these situations it is often necessary to deliberately underexpose the darker areas of a scene in order to preserve highlight details in the brightest areas. While modern DSLR's provide a variety of illumination meters and exposure adjustments, high-contrast scenes can easily exceed the camera's limited dynamic range. One of the first challenges that confront videographers is gauging the proper exposure for each shot. Gamma Control - Exposure's Hidden Dimension And since Nikon Gamma Controls are calibrated to industry-standard grading tools, the selected gamma curve can be freely and accurately fine-tuned in a wide range of video editors without loss of image detail. Unlike previous custom picture profiles such as Technicolor's Cinestyle, which provides a single, non-adjustable gamma curve that attempts to cover all types of shooting conditions, Nikon Gamma Controls enable the user to select a standardized gamma curve that best suits the illumination of each shot. It is comprised of a set of calibrated gamma curves applied to Nikon's built-in Picture Profiles: Neutral, Portrait, Standard, Landscape, Vivid, and Monochrome. Nikon Gamma Controls bring interactive adjustment of the camera's gamma curve to video filming on DSLR's that support Nikon's custom Picture Control profiles. ![]()
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