Making Shadows with Layers

In this tutorial we're going to simulate a shadow cast by an object. Now this is only one of the many ways to make a shadow, but it works well.

We're going to start with two images - a cow in a field and an empty parking lot. Yep - cow's going in the parking lot. Here are the images:

Click to enlarge

Use this image if you want, or put the cow someplace better (McDonald's?)

Here's a larger version of the cow image to play with.

Alright, open up that Photoshop and off we go:

Step 1: With the cow image open, use your favorite selection tool to outline it. I used the magnetic lasso, and then touched up with the polygonal and regular lasso tools at the end. (You can add to a selection by holding the "Shift" key, and you can subtract from the selection by holding the "Alt" key).

Here I've started selecting the top edge of the cow.

Click to enlarge

After you've finished your selection (which might take a while to get just right) be sure to save it by going to SELECT > SAVE SELECTION. Give it a good name and then save your image as a PSD file just in case you need it later. Your selection should look something like this:

Step 2: Now that you have the cow selected, open up the background image you're going to place it in. In our case, we're using the parking lot image. Give the selection a slight feather (1 or 2 pixels should be enough) by clicking SELECT > FEATHER. This will blur the edges a bit and make the cow fit more realistically into the target pic. Hit CTRL-C or EDIT > COPY to copy the cow image, and then hit CT RL+V or EDIT > PASTE to paste the cow into your target background image.

Step 3: If your cow image is too big or too small for the target image, hit CTRL-T to load the "Free Transform" tool. Then, "grab" one of the corners of the selection that appears with the mouse, and while holding the left mouse button PLUS the shift key, drag in or out to change the cow's size. Holding the shift key makes Photoshop change the width at the same time as the height to keep the proportions of your image the same.

Step 4: Once you've got the cow to a reasonable size, open the Layers palette (WINDOW > LAYERS) and CTRL-click the cow layer. This should add a selection around the guy. Pretty sweet, eh? Believe it or not, it gets better.

Step 5: With the cow selected, create a new layer and select it. ClickEDIT > FILL, then fill the selection on its own layer with a solid black. We can adjust the opacity of this layer later.

Your image should look something like this:

Step 6: Now we've got our shadow, so let's make it look like one. Drag the shadow layer below the cow layer but above the background image. Click EDIT > TRANSFORM > DISTORT and click-drag the center "handle" point of the selection box until the shadow appears to be on the same plane as the ground.

Click to enlarge

Use the corners of the distort selection box to add a little perspective if you want. The most import thing is to try and match the direction of the light in the source and target photos. At least if you're going for realism, that is.

Step 7: We're almost there. We have the shadow, it's on the ground, but it doesn't quite look real yet. Keep this in mind: the farther the object is from the light source or the ground, the more dispersed the light is going to be. This means that the shadow will be crisp and dark where the object is close to the ground, and fuzzier and lighter where the object is farther away. In this case, the top of the cow is farther from the ground than the legs, so the corresponding areas on the shadow will act accordingly.

Basically, we want to give the shadow a gradient that is dark at the base/foot area, and a bit lighter at the top/spine area.

Step 8: Double-click the shadow layer to access the "Layer Style" menu. Click the "Gradient Overlay" checkbox, then click the "Gradient" box, as shown below.

Instead of the default black to white gradient, we're going to use black to VERY dark gray. Click the white tab on the gradient bar, then the white block next to the word "Color" at the bottom. I used a dark gray with the hexadecimal number 131313, but use whatever looks good to you.

You should be able to see the gradient in the image above. It's slight, but it will make the shadow more realistic. I used a shadow angle of 103 degrees.

Step 9: Almost done, don't have a........fit. Anyway, change the opacity of the shadow layer to 87% (or whatever looks good to you). Select the "Blur" tool, shown below.

Set the strength to something low, like 20%, and blur the shadow, starting from the legs and going toward the top. Then, start farther from the legs and repeat until the blur on the top of the shadow is more than the blur on the legs. Make sure the "All Layers" checkbox is not checked.

Here's the final photo:

Click to enlarge

And there you have it! Now you can put this cow any old place. Readjust the shadow if need be. Hopefully you can use this one. Show me the results if you do.