The color grading in this tutorial is basically done using curves. It can be seen that the function of curves is very powerful. Pictures have multiple color modes such as RGB, Lab, etc. If you combine curves in various modes, you can create many beautiful effects.
Original picture
final effect
1. First get the grayscale image. There are many ways. Here I use the curve and the saturation mode to get the grayscale image. You must have a way to get a better grayscale image. The purpose of this is just to say that the curve can also be like this. Just for use.
2. The basic effect can be obtained by adjusting the light and shadow with fine curves. Of course, similar selections can also be obtained by calculation methods, but the selections obtained by fine control of curves are sometimes easier to control than the calculation method. In the article, I talked about the application of curve + blend mode and the use of curves to replace calculations and lab curves, which will be touched upon here.
3. Change the blending mode of the curve layer to color, and adjust the blue channel to color the entire image. The adjustment is completed in RGB mode. (Of course you can get the same effect without color mode, but using color mode makes it easier to adjust the color without being disturbed by brightness and saturation. If you get used to it, you will definitely like the layer blending mode. powerful functions).