The acronym HDR comes from the English expression High Dynamic Range , which translates into Spanish as High Dynamic Range . The concept, used in the field of photography , refers to a series of techniques that enable an improvement in the dynamic range of luminance between the darkest and lightest sectors of an image, compared to what can be achieved with standard methods.
No less significant is knowing that HDR has its origins in the 1930s and was created and developed by the American Charles Wales Wyckoff. Specifically, this was a photochemist who carried it out with the clear purpose of ensuring that his photographs had a greater dynamic range than what existed at that time within that area of the image.
An HDR photograph, in this way, displays an image similar to what the human eye can capture, since it achieves a more accentuated difference in lighting per area than that offered by other formats. In the case of the human eye, the adaptation of the iris and other procedures make vision constantly adapt to the range of light seen in the environment, information that the brain processes so that the person sees the multiple variants of the conditions of light. light.
HDR, by displaying a wide dynamic range, can represent the different light intensities of the real world more faithfully . There are several techniques that make this particularity possible.
The measurement of dynamic range is carried out through the different exposure values ( EV ) between the lightest and darkest areas of the image that exhibit some detail: each increase in EV causes an increase in the amount of light. An HDR image is usually obtained by recording several traditional photos and then combining them into a new document using a technique known as bracketing .
Nowadays we cannot ignore the fact that HDR has become an essential element in many televisions. In this case, it must be emphasized that the quality of this technology in those will depend on both the contrast ratio and the brightness delivery capacity they have, as well as the color space that it can reproduce.
Within the field of televisions we also have to add another interesting fact and it is none other than the fact that two different HDR standards have been established: one for what are called OLED televisions and others for televisions. LED LCD, which are identified by being brighter than the previous ones.
Likewise, we must not overlook the fact that it is currently established that there are a series of HDR standards that are already consolidated. In this case, we would have to talk about Dolby Vision, HDR10, HDR10+, HLG or Advanced HDR, among others.