Sergei123
Member | Редактировать | Профиль | Сообщение | Цитировать | Сообщить модератору В новом Фотошопе (CS 2) реализован режим поддержки HDR - High Dynamic Range images. The dynamic range (ratio between dark and bright regions) in the visible world far exceeds the range of human vision and of images that are printed or displayed on a monitor. But whereas human eyes can adapt to very different brightness levels, most cameras and computer monitors can capture and reproduce only a fixed dynamic range. Photographers, motion picture artists, and others working with digital images must be selective about whats important in a scene because they are working with a limited dynamic range. High Dynamic Range (HDR) images open up a world of possibilities because they can represent the entire dynamic range of the visible world. Because all the luminance values in a real-world scene are represented proportionately and stored in an HDR image, adjusting the exposure of an HDR image is like adjusting the exposure when photographing a scene in the real world. This capability lets you create blurs and other real-world lighting effects that look realistic. Currently, HDR images are used mostly in motion pictures, special effects, 3D work, and some high-end photography. In Photoshop, the luminance values of an HDR image are stored using a floating-point numeric representation thats 32 bits long (32‑bits-per-channel). The luminance values in an HDR image are directly related to the amount of light in a scene. This is not so with (non-floating point) 16‑bits-per-channel and 8‑bits-per-channel image files, which can store luminance values only from black to paper white; this represents an extremely small segment of the dynamic range in the real world. You can create an HDR image using multiple photographs, each captured at a different exposure. In Photoshop, the Merge To HDR command lets you create HDR images from multiple photographs. Because an HDR image contains brightness levels that far exceed the display capabilities of a standard 24‑bit monitor or the range of tones in a printed image, Photoshop lets you adjust the preview of the HDR image so it can be viewed on a computer monitor. Some Photoshop tools, adjustments, and filters can be used with HDR images. If you need to print the image or use Photoshop tools and filters that dont work with HDR images, you can convert the HDR image to an 8‑ or 16‑bits-per-channel image. |