Image Trace in Adobe Illustrator is handy for many reasons. If you use the program for illustrations mostly, it's one of the tools usually avoided as you can easily recognize images that have been traced in Adobe Illustrator and because it has it's own "style", it often clashes with whatever style you're working with.
I personally wouldn't recommend using it on an element in an illustration that has a lot of focus, as the viewer's eye will be attracted there instantly. But using Image Trace in background elements to help enhance an illustration or even to create texture and add depth to, for example, a character's clothing (or if you happen to be in a rush), this tool can be really great!
The following assets were used in this tutorial:
I drew this illustration for another tutorial where I explain how I create the painted effect you can see in the screenshot with vector; How to Create a Vector Painted Effect in Adobe Illustrator. I will be using this illustration again for this tutorial to show you how I used Image Trace to create the sky background behind the desert and palm trees.
Before placing the stock photo of the desert behind the illustration, I decided to place a white layer underneath first, setting the Opacity of the layer at 30%. I didn't want the background to be too dark and obvious, keeping the focus on the foreground.
I initially had purchased the Desert Stock Photo to use as a reference for the sand hills when painting them, but then realized the sky was really great as well and since I couldn't come up with anything else, I decided to use it in the background. Vectoring clouds and skies can be a bit tricky sometimes, to me anyway, so after attempting to paint them but not liking the end result, I gave Image Trace a try!
To do this, Create New Layer underneath all the others that hold the foreground, lock all layers with exception of the one we intend to place the stock photo in and then continue to place the Desert Stock Photo in that new layer.
Go to File > Place > Desert Stock Photo. Once it's in the file, size it using the Selection Tool (V) by dragging out the corner (doesn't matter which one). Hold down Shift on your keyboard at the same time to make sure the photo doesn't lose it's proportions.
To turn it into an Image Trace, keep the stock photo selected and then turn it into an Image Trace. You can do this by either clicking on the button titled 'Image Trace' in your navigation bar at the top of Adobe Illustrator (appears when a raster file is selected), or by going to Object > Image Trace > Make.
You can see that the stock photo has now turned into black and white shapes, lacking in a lot of detail. We're going to adjust this by bringing forth the Image Trace options; Window > Image Trace.
In this case we want to bring back the colors the stock photo originally had. To make that happen, you'll see the option Mode in the Image Trace options with a drop down menu beside it. Click on the drop down menu and choose the option Color.
As you can see the shapes are still quite rough and not like the stock photo at all. We're going to bring back the detail and smooth out the shapes by changing the setting beside the Palette option. Before it was set to Limited and now we are going to change it to Full Tone. You can see that the shapes have smoothed out and more colors have been added.
The shapes are still very easy to distinguish though, and we want to smooth the color blends in the clouds further so it doesn't look as choppy. To do this, we are going to change some settings in the Advanced section of the Image Trace panel. If they aren't open already, click on the small arrow on the left of Advanced and the options will appear. Usually the arrows on the bars of Paths, Corners and Noise will be set somewhere in the middle. We're going to change them so the as much detail as possible from the stock photo returns in our image trace.
First we'll lower the Noise to 1px. The more Noise you add, the rougher the edges of the shapes will be. Since that is not what we want for this illustration, we're bringing it all the way down to smooth the shapes out as much as possible.
For Paths and Corners we're setting them both at a 100%. It will make the file heavier, but the shapes will follow the stock photo's appearance as closely as possible.
The shapes are still not as smooth as they are in the stock photo of course, it is very close though and since I never intended for the sky to be quite that dark, it's the result I was looking for. The background is very obvious at a 100% Opacity, so we're going to lower it, which will also give the illustration more of a day time atmosphere rather than a sunset atmosphere.
Select the Image Trace layer and lower the Opacity to 20%.
Finally, you can create a new layer on top of all the others and create a shape over the illustration, filling it with a gradient of your choice and playing around with the Blending Mode and Opacity to add more light moods to the scene, atmosphere or to unify the overall coloring of the drawing.
I was quite pleased with the result where it concerned the background and how it faded into the painted sand hills and palm trees, so I created a gradient layer on top of all the other layers, using the most prominent colors in the overall illustration; Blue, purple and orange. I set the Blending Mode to Soft Light so it would be very subtly, and lessened the effect further by lowering the Opacity to 40%.
Congratulations! You're Done
And that's it! Image Trace can really help finish the look of an illustration, as shown in this Quick Tip. I think the main thing to keep in mind is to use it subtly so it doesn't overwhelm your drawing or become more prominent than what you drew by hand. I hope some found this useful and that it'll help you in your future illustrations!
If you're interested in finding out more about the painted effect used on the character and the tank, be sure to check out the other tutorial; How to Create a Vector Painted Effect in Adobe Illustrator. Alternatively, if you're wanting to find out more about Image Trace, check out this awesome screencast tutorial on how to use Image Trace.