What is 18 percent grey in photography?
In photography, painting, and other visual arts, middle gray or middle grey is a tone that is perceptually about halfway between black and white on a lightness scale; in photography, and printing, it is typically defined as 18% reflectance in visible light.
What percentage is a grey card?
A gray card is exactly as it sounds: A card that is gray. More specifically, a gray card is middle gray, or 18% gray.
Why is it called 18% grey?
So, where does 18% come from? 18% grey comes from the world of print,m and is based on reflection. An 18% grey card reflects back 18% of the light that hits it. And it is actually the geometric mean between white paper (95% reflective) and black ink (3.5% reflective).
Why is 18% middle gray?
You are probably asking yourself why do we refer to it as 18% grey rather than 50%? The simple answer is that our visual perception of brightness is not linear. This is why the middle grey is referred to as 18% grey. At the midpoint between white and black that shade of grey only reflects 18% of light.
Why do you use a grey card to set white balance?
A grey card is designed to help photographers to adjust their exposure and white balance settings consistently by providing a reference point. The reference point will prompt your camera to compensate for any illuminant color in the space where you plan to shoot by adjusting the white balance and/or color profile.
What ire value should you set an 18% GREY card?
A Kodak Standard Grey Card has a reflectance of 18% which renders as a “normal” mid grey exposure density on film. In video terms this equates to 50% or 0.5 volts IRE.
Why do photographers use a GREY card?
Why is mid grey 18%?
18% grey comes from the world of print,m and is based on reflection. An 18% grey card reflects back 18% of the light that hits it. And it is actually the geometric mean between white paper (95% reflective) and black ink (3.5% reflective).
What is the use of a gray card in photography?
A primary use of gray cards is to provide a standard reference object for exposure determination in photography. A gray card is an (approximate) realization of a Lambertian scatterer; its apparent brightness (and exposure determination) therefore depends only on its orientation relative to the light source.
What is a photographic grey card?
A photo of the gray card is taken and used to set white balance for a sequence of photos. For post-processing white balance, a photo of the gray card in the scene is taken, and the image processing software uses the data from the pixels in the gray card area of the photo to set the white balance point for the whole image.
What is a camera gray card?
Gray Card (~) A gray card is a middle gray reference board, sheet or similar material, typically used together with a reflective light meter either in camera or hand held, as a way to produce consistent image exposure and/or color in film and digital photography. You can use a ~ for WB reference instead of white.