tailieunhanh - Sử dụng photoshop cs5 part 37

Sửa chữa màu bằng cách sử dụng Curves Bằng cách sử dụng một lớp điều chỉnh Curves, bạn có thể điều chỉnh các giá trị trong một phạm vi hẹp âm, chẳng hạn như những điểm nổi bật, âm quý, midtones, ba phần tư tấn, hay bóng tối. sửa chữa chính xác có thể được áp dụng cho các kênh composite (tất cả các kênh trong hình ảnh kết hợp) hoặc các kênh màu riêng lẻ. Trong các bước này, bạn sẽ sửa chữa âm đầu tiên, sau đó điều chỉnh màu sắc. | 222 Chapter 13 Correcting the color using Curves By using a Curves adjustment layer you can adjust the values in a narrow tonal range such as the highlights quarter tones midtones three-quarter tones or shadows. Precise corrections can be applied to the composite channel all the channels in the image combined or to individual color channels. In these steps you will make tonal corrections first then adjust the color. To correct color and tonal values using a Curves adjustment layer Part 1 Apply tonal adjustments 1. Open an RGB image that needs a color adjustment. A 2. On the Adjustments panel click the Curves button Choose Curves Display Options from the Adjustments panel menu check all four of the Show options described in the sidebar at right leave Show Amount Of on the default setting of Light 0-255 then click OK. 3. If the contrast in the image needs improvement do either of the following The Input sliders affect the lightest and darkest tonal values in the image. To increase the contrast darken the shadows and brighten the highlights drag the black shadow Input slider and white highlight Input slider inward so they align with the ends of the histogram. The steeper the curve the greater the contrast. To increase the contrast by establishing the lightest and darkest values in a high-contrast display of clipping called Threshold mode Alt-drag Option-drag the black slider until a few areas of black appear and the white slider until a mere smidgen of white appears. Note that this can also be done in Levels. 4. For more targeted adjustments do any of the following Drag part of the curve a point will appear on it. For example to lighten the midtones drag the middle of the curve upward or to darken the midtones drag the middle of the curve downward. When a tonal value is lightened its Output value after adjustment becomes higher than its Input value the original brightness value . When a tonal value is darkened its Output value becomes lower than its Input value. A .