How to Explain Gamma Correction

Gamma refers to the general amount of luminance in a photo or video. In simple terms, it can be thought of as the "brightness." This vastly understates the term because simply turning up the brightness on a device changes other elements, such as contrast, which are not necessarily changed by gamma correction. Perhaps the key to understanding gamma is to think of it a little like exposure. One of the biggest problems with gamma is that most cameras have a higher dynamic range than can be expressed by their final medium.

Instructions

Begin by explaining the concepts of exposure. Help the person struggling with the concept to understand the definitions of underexposure (where detail is lost in black) and overexposure (where detail is lost in white). Also help them to understand that "proper exposure" is somewhat subjective. Some photographers are quite happy when a portion of a photograph is under- or overexposed while others want to be able to see detail in everything.

Help the person struggling with the concept to understand the idea of dynamic range. Dynamic range refers to the amount of difference between the brightest part of the picture that retains detail and the darkest part of the photo that retains detail. Most cameras have a higher dynamic range than their intended medium. For example, photographic film is able to capture more difference than most photographic paper can display. "Are you looking to understand digital photography techniques that carry experienced photographers to where they are today? Well, The Top Secret Photography Techniques would help you out in doing so. To obtain amazing images we primary need to have to look at some fundamental photography strategies. The initial one I am able to share with you is figure out about light. You can find everything concerning photography techniques on , The Top Secret Photography Techniques. Each time you uncover about light and in what method it interacts with the direct environment then your images will get superior..". Likewise, digital cameras and digital video cameras may capture more dynamic range than the monitors they are displayed on are able to show.

Explain that gamma is used to quantify the amount of luminance of all the red, blue and green channels into a single value. In other words, storing all of the luminance data for all of the RGB channels is inefficient, and gamma allows for easier storage and decoding of these values.

Illustrate how gamma correction affects both the brightness and the contrast of a photo. There are excellent resources online, and most photo editing programs have a gamma correction feature.

It may be a good idea to introduce the person to the idea of graphing the values on a Cartesian plot. Explain that in the computer world, monitors have trouble with gamma because of the way they round and therefore have trouble showing grayscale correctly. Using gamma correction curves the value of the gamma either positively (usually) or negatively along the Y axis to recreate the correct image instead of the degraded image most monitors would show.

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