Tracing and vectorization techniques in Adobe Illustrator

Vectorization is the process of converting images composed of pixels into graphics defined by mathematical curves and lines, and in the field of design with Illustrator it is a key skill. The truly powerful thing about going from bitmap to vector is that the image can be scaled without losing sharpness., opening the door to large-format printing, clean animations, and a more flexible workflow for designers.

Although there are online services today that promise fast results, when you are looking for fine control, good shadow management and a clean result, Adobe Illustrator offers a set of tools—manual and automatic—that make the differenceIn the following sections, you'll learn how to approach vectorization with proven methods and settings, when each approach is appropriate, and how to optimize the final file so it weighs less, is easier to edit, and looks perfect at any size.

What vectorization means and why it's worth it

In design, “vectorizing” means converting a raster image (JPG, PNG, TIFF, etc.), consisting of a grid of pixels, into a structure based on paths and nodes. The key advantage is lossless scalability: when scaling up, vectors recalculate their shapes. and maintain clean edges, while a bitmap photo or logo becomes pixelated when its resolution is exceeded.

In addition to sharpness, there are a number of other practical benefits: Vector graphics usually weigh less than a high-resolution photograph, they are much more easily modified (colors, shapes, thicknesses, blending of lines) and can be adapted to very different uses, from a tiny favicon to a billboard.

If you're wondering where they fit best, think about logos, icons, infographics, fonts, or illustrations with defined edges. For complex images with gradients and fine noise, Illustrator also helps with specific path settings., although the criteria and the refined manual remain decisive.

Difference between raster and vector images

A raster image stores information pixel by pixel and, therefore, When you enlarge it beyond its resolution, the “little squares” appear.. It's the natural format for photographs and scenes with smooth detail and tonal continuity, but it's not flexible when it comes to scaling.

A vector file, on the other hand, describes shapes with mathematics: segments, Bézier curves, fills, and strokes. Resizes without losing quality and retains clean linesIt is ideal for visual identities, pictograms, and technical elements that require precision.

The most common vector formats are AI (Illustrator native), EPS, SVG and PDF, compatible with most printing and digital publishing workflows. Having the logo in vector format allows it to be applied with confidence, from an email signature to an XXL banner.

Two ways: manual tracing with Pen and automatic tracing

Illustrator allows you to vectorize in two complementary ways: by drawing yourself with the Pen for surgical control, or by using the Trace/Image Trace engine to automate much of the process. The choice depends on the type of image, the level of detail and the result you are looking for..

Manual vectorization with the Pen tool

1. Preparation: Open Illustrator, create the table with the measurements you need, and place the sketch or image on a reference layer. Working with a separate layer for the original avoids confusion and helps you compare progress..
2. New working layer. Create a clean layer to draw your strokes. Activate the Pen tool and zoom in to follow the contours. Toggle between clicks and drags to open and close the curves according to the profile of the image.
3. Geometric shapes when appropriate. For eyes, glasses, or round objects, it's faster to start with an ellipse or rectangle than to draw everything by hand. Using basic shapes allows you to maintain proportions and save time.
4. Stroke contrast. With the stroke selected, change its color in the Color panel to make it stand out from the background. Note: change the color of the stroke, not the fill, to see where you are going..
5. Layers by element. For medium-sized or complex illustrations, divide the work into pieces: eyes, mouth, hair, clothing, background, etc. The more layers you organize, the easier it will be to edit without touching what you don't touch..
6. Make mistakes on the fly. If a curve isn't perfect, correct it right away with Direct Selection (A) or reposition nodes. Rectifying is part of the flow and saves you tedious fixes at the end..
7. Closing shapes. To fill with color, you need closed paths; return to your starting point and close them even if the outline won't be visible. Without closure, the filling is not applied as you expect.
8. From stroke to fill on specific elements. If you've drawn details like the pupils with a stroke, it's a good idea to convert them to shapes: Object > Path > Create Outline. This way you can color them and combine them with other figures..
9. Review without the reference. Occasionally, hide the sketch layer to evaluate the overall picture with fresh eyes. Viewing the vector “bare” helps you spot odd proportions or unnecessary lines.
10. When there are many small curves in a row. In small, random, curved streams, wisps, or swirls, the Pencil tool can speed things up. Then you smooth and clean to leave it fine.
11. Details and post-production. Add small touches that add character; if a subtle flaw persists, you can always retouch in Photoshop. The Illustrator + Photoshop combo remains a classic for a reason.
12. Color and save. Once drawn, move on to coloring with swatches and palettes. Save the project in .ai to maintain editing and create versions in the formats you need..

Automatic vectorization with Image Trace

1. Select the image and open the panel. With the photo or logo active, go to Window > Image Trace (or Image Trace, depending on the version). Without selecting the image, the command appears disabled; if it remains inactive, check that the layer is not locked.
2. Choose a preset. Some of the most useful ones include Logo/High Contrast, Black & White, High Fidelity Photo, Silhouette, or Technical. Each preset prioritizes a different type of detail and simplification, perfect for starting without starting from scratch.
3. Adjust the controls. Play with Threshold (defines what's considered "black" in B&W), Number of Colors (in color), Plot Areas, and Corner (precision around edges and corners). These sliders are the key to balancing detail and simplicity..
4. Expand to edit. When you're satisfied with the preview, press Expand to convert the tracing to real vectors. Ungroup if necessary to edit piece by piece and clean areas that do not contribute.
5. Manual refinement is essential. Even if the tracing is progressing well, it's often necessary to use Direct Selection (A), erase unnecessary points, and refine curves. The human touch leaves the file cleaner and lighter.
6. Save and export. Keep an editable AI version and export to SVG for web, PDF for compatibility, or EPS if you work with certain print workflows. Choose the format according to the destination of the graph.

Case studies: B/W, grayscale and color

Black and white (simple logos and graphics)The B&W logo preset is usually sufficient. The gently jagged edges of the original become crisp when vectorized, and there's often no need to touch advanced settings. After Expand, the number of nodes is reduced, which makes it easy to modify thicknesses or remove, for example, the stroke of the outer rectangle if it is not needed.

Grayscale (portraits and soft reliefs)With the default grayscale setting, you'll see layered areas (e.g., hair or forehead), and when you expand, you'll see a complex mesh with many points. To be useful it is advisable to simplify first: Reduce the number of grays (e.g., to 8), and lower the Path and Vertex percentages for less aggressive corners. This will give you larger, more manageable shapes.

Once expanded with that more restrained configuration, you can delete excess polygons to retain essential contours (such as outlining the face and “cutting” a hairstyle), and edit nodes as if you had drawn it with the Pen from scratch.

Color (scenes and illustrations with various shades). Set Mode: Color and a limited palette (30 colors is usually a balanced base). Adjust Strokes and Vertex to around 10% and increase Noise to 5 px if there are very fine details causing shakiness. You will get a result with many points, common in complex images; remove what's not needed, recolor pieces (changing hair tones, for example), and embed it in another composition if needed.

Optimization after tracing or tracing

Once vectorized, it's time to fine-tune. Fewer anchor points usually equals smoother curves and lighter files., which improves performance and makes editing more comfortable.

Smooth Tool. It's next to the Pencil tool and lets you smooth out a knotty path by simply brushing over it. You will see how unnecessary points disappear without losing the general shape.

Simplify: Object > Path > Simplify. Select the object and open the dialog box to adjust curve and angle precision with a preview. Parameters such as 94% accuracy and 111° angle can drastically cut the number of points maintaining the essential geometry, although each case requires its own balance.

Other useful tools: The Pathfinder tool for joining, subtracting, and dividing shapes; Expand Stroke tool for converting strokes into solid fills; and the Recolor Artwork tool for quickly exploring alternative palettes. Save libraries Symbols and AI parts accelerate future work.

Good practices that make a difference

• Organize by layers and groups From the very beginning: components separated by layers and groups will allow you to lock, hide and select precisely without touching what you don't.
• Converts details drawn as a stroke to an outline (Object > Path > Create Outline) when you need to fill, blend, or apply shape effects to them.
• Switch between viewing with and without the reference to detect errors in the curves' rhythm, inconsistent weights, or shapes that don't fit. This "close-up" look reveals things that aren't visible in the photo below.
• When there are tiny, consecutive curves, grab the Pencil, then soften/simplify. You'll save time on areas like splashes, highlights, and embellishments.
• Prepare the raster image beforeIf possible, clean up the contrast and reduce noise in the original to aid in the tracing. A sharpening point and well-placed levels greatly improve the result.
• Think about the end useIf you're printing large, aim for less banding and more smoothness; if you're printing on screen, prioritize low weights and clean SVGs. Context rules the configuration.
• Alternatives and resources: There are online solutions and vectorization programs such as Inkscape or Corel vectorizing tools, which are useful depending on the case. Even so, Illustrator stands out for its precision in shapes, shadow management and file control. when the quality bar is high.

Workflow and output formats

Save a master version in AI to maintain layers, appearances, and non-destructive editing. That file is your “source of truth” for lossless iteration..

Export according to your destination: SVG for the web (lightweight, editable, and scalable in interfaces), PDF for universal compatibility and prepress, EPS if you work with systems that require it. If the vector is going to be animated or responsive, SVG is usually the most versatile option..

If you need to quickly adapt the look, explore Recolor Artwork to remix palettes and generate color variations. It's a fast way to test builds without rebuilding anything..

When to choose each vectorization method

Manual with Pen: For logos, isotypes, icons, and silhouettes that require absolute control over every curve; even when the original is very dirty and you prefer to reconstruct it with millimeter-precise cleanliness.

Automatic with Image Trace/Trace: for scanned sketches, illustrations with light color masses, or stylized photographs when you're looking for a quick base that you'll then polish by hand. The key is to adjust and simplify before and after expanding..

Training and continuous improvement

If you want to accelerate your learning, consider Illustrator-specific courses focused on vectorization and professional workflow. From short, practical online training to advanced training courses in graphic arts, there are options for all levels and goals.

Mastering tracing and vectorization in Illustrator involves understanding when to draw by hand and when to let the trace do the first sweep, how to adjust Threshold, Colors, Path Areas, and Corner for each image type, and how to clean up afterward with Smooth and Simplify. With well-organized layers, closed strokes, details converted to outline, and proper export (AI, SVG, PDF, EPS), your graphics will maintain impeccable quality, contained weight and a flexibility that will save you more than one project.

Related article:

How to vectorize a PDF file: Complete step-by-step guide

Isaac

Passionate writer about the world of bytes and technology in general. I love sharing my knowledge through writing, and that's what I'll do on this blog, show you all the most interesting things about gadgets, software, hardware, tech trends, and more. My goal is to help you navigate the digital world in a simple and entertaining way.