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Shadows are a very important aspect of any photo manipulation. Just as it happens with lighting effects, if the shadows are used the right way, you can end up with a stunning image. In this tutorial I will show you a few techniques I use to create realistic shadows and lights with Photoshop.
The first step will be only theory to help you understand how lights and shadows work and on the following steps I will show you how to actually create the shadows.
1) Light source and shadow angles.
Before even starting to do anything on you image, you must decide whether you need shadows or not. To guide yourself you must first identify the main light source.
You can see that the light source on the original image is on the top left side. On the manipulated image, the sky and the clouds are also illuminated on the top left side. You should always respect the direction of the light. You have to establish which elements of the image will serve as your guide to make the lights and shadows.
Below you have a similar case. But this time the light source comes from the right side and again the artist used as guide the highlights of the model’s body highlights when he/she made the manipulation.
Sometimes there are no reference points to help you identify where the main light source is but the existing shadows on the image can help you. Here you have an example.
The original image didn’t have the road sign, I added it with photoshop. Assuming I had no reference points to help me decide where the main light source is (in this case the sun), I made the shadow of the road sign using the shadows of the man and the girl as guide. I made it using pretty much the same angle and the same opacity. If the original shadows that you use as guide are blurred, you should apply Gaussian Blur to your shadows to make them look as close as possible to the existing original shadow.
That’s the basic theory. For short, you have to identify the light source in order to know how to create the shadows. On the next steps I will show you how to create the actual shadows from scratch. I will show you my personal technique but you can adapt them to your own style. There are different kinds of shadows and to make things easier for me to explain and for you to understand, I will give them different names.
A) Contact shadow
I will call this kind of shadow “contact shadow” because I don’t know the real name of it. This is a very important kind of shadow because it actually tells you that the object is sitting on the ground or really close to the surface. On the image below you have an example of a real shadow where you can clearly see this type of shadow.
Replicating this kind of shadows in photoshop is not difficult but it requires some practice. As example I took an image used on another tutorial that I made. I subtracted the model from its original background I put it over a new one to start working on the manipulation. As you can see it looks a bit dull, it is obvious that the shadows are missing and it looks like the model it’s floating in the air.
The way I create the shadows that you can see on the image below is this: I take a medium size brush (depends on the size of your manipulation) I set the brush Hardness to about 30% and the brush opacity to about 25%. Then, I start brushing the edges of the object that’s in contact with the ground. I brush the edges from the inside out, so to speak. See the image below for more details.
This is a before and after the so called contact shadow as I named it, I don’t know the technical name of it.
B) Soft Shadow
This kind of shadows are probably more important than the contact shadow because these are more visible and if you do it right, maybe you don’t even need the “contact shadows” explained above.
Here you have a bit more of freedom because you don’t have to be very precise. Just take a soft brush, set the strength to 20-45% and brush around the object that you’re working with. Keep in mind that as you move away from the object, the shadow must be less opaque because it fades away.
Take a look at the image below. I painted the shadows using a big soft brush with low opacity (20% or something like that). As you see, you cannot distinguish the shape of the girl in the shadow because it’s too blurry but it definitely adds realism to the scene. Also notice how the shadow is less intense as you get away from the body. This was all made with the mouse, not a tablet.
C) Cast shadows
If you want to create more realistic shadows in Photoshop, than you have to use another technique. As almost always in Photoshop, there are multiple ways of achieving the same result. Briefly, this technique consists in using the shape of your object to create the shadow.
One way to do it is to duplicate the layer and then reduce the lightness to 0. Then, you move the duplicated layer below the original one and rename it to shadow if you want.
I already made a quick video demo of how to make this kind of shadows. You can watch the tutorial here. After that, you use the distort tool to arrange the shadow as you like. You can apply Gaussian Blur if you want a blurry shadow and also adjust the opacity of the layer.
Then I applied some Gaussian Blur, reduced the opacity and used a Layer Mask and the Gradient tool to make the shadow fade away. Then, with the Distort tool (Ctrl+T or from Edit>Transform>Distort) I tilted it a bit.
The second way of achieving the same result as on the picture above is by using layer styles. I think it’s easier and quicker. I’ll show you a REALLY COOOL TIP that not many people know.
Just open the layer styles window (in my example the TOWER layer) and add Drop Shadow. The most important setting here is the Shadow Size. With Size, you control the amount of blur you want on your shadow.
Increase Opacity to 100% because you can lower it later if you want using the Opacity slider on the layers palette. I used high Distance values in this example so that I could see the entire shadow better but the Distance is not important.
Now comes the cool part. You can turn this drop-down shadow effect into a layer. Right click over the Drop Shadow effect layer on the Layers Palette and choose Create Layer.
That will create a new layer with the same Blend Mode and Opacity settings. You can do this with any effect. After that, flip the layer, reduce opacity of needed. Repeat the same as explained above in order to tilt it.
I think that’s pretty much all I could say about shadows. Let’s go with the lighting now. I will just show you a few techniques that I use to create realistic lights.
D) Casting lights
I want to show you how I created the light effects shown in the image below. It’s from a manipulation that I’m working on. I will write a full tutorial about it.
Making this kind of light effects in Photoshop is not difficult but you have to think a bit if you want to cast the light realistically. Blend modes are very important here. Don’t be afraid of making each light effect on it’s own layer and using different blend modes for each of them.
The first thing I created was the light source. I took a fairly big soft brush with yellow color and I painted a big dot. Then I went through all the available Blend Modes to see which one works best.
Keep in mind that blend modes work with luminosity values. If the light don’t look as you want it with any of the available blend modes, try using a darker, less saturated color. In this example I used a dark yellow to make the light glow.
Next I created the final glow using the Lens Flare filter from the menu Filter>Render>Lens Flare. I created a square selection, filled it with black on a new layer and I added the flare centered on that black square. Then I changed its color to yellow with the Hue/Saturation adjustment and I changed the layer’s blend mode to Screen to hide the black area of the square.
When the light source is made, you will have to replicate the light that comes from it on the other objects such as the ground or walls. The most common way of doing that is by hand using a soft brush and in this case the yellow color.
I found out that the Color Dodge, Vivid Light or Linear Dodge (Add) are the best blend modes for light effects but as I said, it depends on the colors and luminosity levels on your background. The realism of the light depends on where you place it.
As you can see on the image above, adding a light on the ground gives this manipulation even more realism. It was made using a big soft brush, yellow color and Color Dodge blend mode, than I used the Distort Tool (Ctrl+T) and I squeezed it horizontally. Even so, by adding another light on the wall on the left can make this even more realistic. So, as I said above, it’s about where you place the light.
To make the light on the wall I just duplicated the ground light and flipped it.
E) Surface Lights
Another way of making a different kind of light is actually using layer styles. This technique can be used when you have the light coming from one side of the object or from behind.
The technique consists of adding some Inner Shadow and using a Blend Mode that works well. Using the same blend mode not always works, you’ll have to try. The objective is to recreate the light on the edges of the object.
The color of the light depends on if you’re working on a daylight manipulation or night scene. If you use the Dodge or Vivid Light blend modes, you must use dark colors because these blend modes will make them look bright. It’s a trial and error process until you find a color with the right illumination value that works ok with a particular blend mode. Also, the effect doesn’t necessarily have to be very strong. Even a soft effect will change the look of your object.
I made a quick setup to illustrate what I just explained. It’s just a rough setup but that’s fine. Take a look at the image below. I applied an Inner Shadow with the settings shown in the image above.
Here you have another example on a manipulation by VinternnV from deviantART.
This techniques has it’s flaws. When using the inner shadow settings, you will often create this light effect on areas that you don’t want.
I usually increase the Distance setting and Change the angle to match the light source direction but even then you can have unwanted results. Increasing the Size setting, you will get a smoother effect but but usually only a thin “line of light” is needed for a good look. See image below for more details. I made the effect really extreme so that you can see better.
As you can see on the picture above there are some unwanted effects as result of applying the Inner Shadow to create the light. In this particular example it doesn’t look that bad but let’s imagine you don’t want to have the light effect on the area that I circled on the image above.
How do you get rid of that without affecting the areas that are ok? You can’t use the eraser tool because this is a layer style. I had a really hard time with this but I eventually found a way around it.
The solution is to convert the style (the inner shadow in this case) into a layer on its own, just like I explained when I talked about the shadows. I bet not many people uses that feature in Photoshop but it’s really useful for example when you want to use an effect that you already used. For example if you want to use two different drop shadow effects.
So, extend the effects layers, right click on the effect you want and select Create Layer. Doing that will automatically create a new clipping mask layer with the opacity and blend mode settings you set on the layer style. After that, you can create a layer mask and mask the areas you don’t want.
F) Global light
The last type of light effects is the global light which I create using the Lighting Effect filter. I apply this filter on almost all my manipulations as a final step. It’s an effect that will make 99% of your manipulations look better. This is a destructive filter, in other words, once you apply it it changes your image permanently and it cannot be undone. You can find the Lighting Filter on the menu Filter>Render>Lighting Effects.
But there is a way of applying this filter non-destructively, if you convert the layer into a Smart Object. You can convert a normal layer into a smart object from the layers palette. Right click the layer and choose “Convert to Smart Object“. That’s all about shadows and lighting. I hope you learned something. It’s all about practicing these techniques and experimenting by yourself.