The use of light and shadow in the synthesis of PS

The first is a theory that helps you understand how light and shadow work, and then teaches you exactly how to deal with shadows in practical applications.

　　Light source and shadow angle

Before you do any image processing, first determine if you need a shadow, and then determine the direction of the main light source.

As shown above, you will find that the light source in the original photo is in the upper left of the heroine, so you should follow the direction of the light source, and in the final synthesis of the photo the source of the light is in the top left of the heroine. Some of the elements in the photo can be used to find the direction of the light source to guide the process of lighting in the synthesis. Here's a similar example. But this time the light source direction on the right, the designer uses the same processing method, in the synthesis although changed the scene, but still follows the light source from the right, the shadow on the left.

However, sometimes there is no obvious light source as a reference, at this time can use the object in the scene projection to determine the direction of the light source. Here's an example:

The road sign in the original photo has no shadow, it doesn't feel real, so we're going to add a projection to make it look real, there is no obvious light source in the picture, but you can see the man and the girl in the picture in the right rear of the character, so that the projection of the Signpost should be in its own right rear, as shown below:

The above is just the foundation of the theory, below I will teach you some of my skills to deal with light and shadow, for the convenience of understanding I give different shades of different names.

　　One: Contact Shadow

I call this shadow "contact Shadow" or "Touch Shadow" because I don't know what name it is. Haha, this is a very important shadow that can tell us that the object is placed on the ground or close to a surface, and that the position of the statue in contact with the ground is such a shadow, This shade is darker, but not pure, and has a certain degree of transparency and edge softness.

It's easy to make this kind of shadow in Photoshop as long as you practice, as in the following example I put the model from the original photo into a new synthetic scene, you can obviously feel the picture is very dull, no shadow model looks like floating in the air.

Let's give him a little bit of shadow to try, as shown in the following figure, set a medium size brush (depending on the size of the picture), hardness of about 30%, transparent about 25%, front color black, and then at the edge of the object to draw, from inside to outside of the drawing.

Now look at the picture below, is not feeling the model is standing on the ground:

　　Two: Soft shadows

This kind of shadow is a particularly important shadow that can make your synthetic reality a notch. And you have a greater degree of freedom in drawing this shadow, just set a softer brush, 25%-40% intensity, and draw around the object. Remember that the opacity of the shadow gradually fades from object to distance.

As shown below, I use a large soft, low transparent base (around 20%) to draw a shadow around the object, you can see that you can't tell the shape of the girl's shadow, because it's too blurry, but it definitely adds to the reality of the scene, and notice how the shadow fades away from the body part to the distance.

　　Three: Projecting shadows

This if you want to create a more authentic effect, you're going to have to learn another shadow, projecting a shadow that is projected onto the ground or other surfaces as a result of an object blocking the light, so the shadow is greatly influenced by the shape of the object, and in Photoshop we generally use the shape of the object directly to make this shadow.

Creating the same effect in Photoshop can be accomplished in a number of different ways, depending on which method you are accustomed to or like, and simply introduce several ways to quickly create a cast shadow:

Method One:

As shown in the following illustration, copy the tower layer and then use the hue/saturation command to reduce the visibility to zero. Then change the command to flip position adjustment and deformation, add a bit of Gauss blur, appropriate adjustment of transparency, and based on the principle of fade from near to far shadow, with a mask or eraser to make appropriate adjustments on the OK.

Method Two:

This method is particularly fast, and many people do not know that you can use layer style separation to quickly make projections. Open the Layer style panel, add a projection, adjust the parameters to get a soft edge projection, where you can adjust the transparency of the projection, you can also control the opacity of the layer after the separation of its transparency. When you are sure to right-click on the layer style symbol on the right side of the layer, select Create layer to separate the projection you just set on the separate layer, and then you can change the position and transparency like method one to achieve projection production.

There are a lot of ways to make projection projections, and there's not too many examples here, and you're doing it the way you're best at it. Now let's talk about the technique of light processing. Category:

• PS Composite Picture Tutorial