Shulou(Shulou.com)11/24 Report--

The curve can be seen in many image editing software, whether it is the professional Photoshop or the picture editing function of the mobile photo album. In the final analysis, it is because it is easy to use and is one of the necessary painting techniques.

The use of the curve is also very simple, but many beginners think it is mysterious and complex. I think it must be because of the name-it must be very difficult for a curve to be combined with a picture because it is clearly a line.

Today, I will explain to you from the most basic principles of the curve to ensure that you can thoroughly learn how to use the curve after reading it.

Basic principles A photo in rgb mode is usually numbered with three numbers, representing the values of red, green and blue respectively.

For example, 0, 0, 0 means red, green and blue are all 0, which is black. 255, 0, 0 represents red 255, green and blue are all 0, which is red. 255,255,255 means red, green, and blue are all 255, which is white.

When you open the curve, you will look at these numbers. You can not only see, but also modify these numbers. When the number changes, so does the color of the photo. This is the principle of curve revision.

There is another option on it. When you select "RGB", the curve changes all color values. Selecting "R" will only change the red value, the same goes for others.

The curve has a horizontal axis and a vertical axis, the horizontal axis represents the original value of the photo, and the vertical axis represents the modified one. If you haven't modified it (it can be understood that the modified one is exactly the same as before), the curve is 45 °and 0 corresponds to 0255, which is easy to understand.

Now that we create a picture of 128, 128, 128, we select the R curve and drag up at about 128 on the horizontal axis, and then we find that the value of the photo changes to 200, 128, 128, and the photo turns red. If we choose the RGB curve to drag up, the photo becomes 200,200,200, and the brightness of the photo is improved.

The above are the principles and examples of curve revision. Let's take a look at some common operations.

02. Common operations 1. Change the brightness to drag the curve up to increase the brightness, and drag the curve down to decrease the brightness.

It is very natural to improve the brightness of the photo through the curve, and there will be no overall whitening, graying, lack of contrast and so on, so the photographer prefers to adjust the brightness with the curve rather than the traditional "brightness / contrast" and "brightness" functions.

Next, I will give you a demonstration. The left picture uses the curve to improve the brightness, and the right picture uses the brightness function to improve the brightness. Which do you think is more natural?

two。 Change the contrast by pulling down on the left and rising on the right to form an S-shape, which can increase the contrast.

This is easy to understand. It makes the dark place darker and the bright place brighter. This is the essence of increasing contrast. The greater the bending of S, the more obvious the increase in contrast.

Now that you have taught to increase the contrast, will you use the curve to reduce the contrast?

3. Film curve do not know if you have seen such a picture, there is a taste of retro film.

Their secret is that the darkest place is not black, and the brightest place is not white, which reduces the contrast appropriately.

Raise the leftmost end of the curve a little bit, lower the rightmost end a little bit, and then pull a small S shape to complete the film curve.

4. Select the red curve for a special color effect, and the highlight rises slightly. Select the blue curve, slightly lower the highlight, choose the green highlight to reduce, strengthen the sky color, and the revision is done.

Select the red curve and lower the rightmost end. Choose the green curve, lower the rightmost end, choose the blue curve, raise the leftmost curve slightly, and the melancholy blue adjustment is done.

This article is from the official account of Wechat: photography Research Society (ID:shoujiPhotography), by Zhang Xiaozhang.

Welcome to subscribe "Shulou Technology Information " to get latest news, interesting things and hot topics in the IT industry, and controls the hottest and latest Internet news, technology news and IT industry trends.