Illustrator CS4 One-on-One: Fundamentals
Illustration by Don Barnett

Trapping an object with an overprint stroke


From:

Illustrator CS4 One-on-One: Fundamentals

with Deke McClelland

Video: Trapping an object with an overprint stroke

In this exercise, I'm going to show you how to create a trap in Illustrator using an overprinting stroke. Now the technique itself is very easy. You create a stroke and overprint it. That's all there is to it. However, conceptually it's difficult because you need to know when and why you need a trap in the first place. Most folks, even those folks who have been working in the business for years who know what trapping is, most of them don't know when you actually need a trap. So I want you to be one of the people who does know this, because it's very important. Most of the time, you don't need to worry about trapping, but sometimes you do and when you do, you really do. So I'm going to demonstrate that in this document. I have gone ahead and saved my progress so far as Overprint document.ai found inside the 11_ printing folder and I'm going to move my Separations Preview palette down here.
Expand all | Collapse all
  1. 42m 8s
    1. Welcome to One-on-One
      1m 58s
    2. The Welcome screen
      3m 3s
    3. Creating a new document
      5m 6s
    4. Advanced document controls
      4m 43s
    5. Saving a custom New Document Profile
      8m 46s
    6. Changing the document setup
      4m 21s
    7. Special artboard controls
      4m 58s
    8. Accepting artboard changes
      2m 19s
    9. Saving a document
      4m 33s
    10. Closing a document
      2m 21s
  2. 1h 0m
    1. Adobe Bridge
      56s
    2. Opening an illustration
      4m 45s
    3. Modifying an illustration
      6m 27s
    4. Saving changes
      4m 58s
    5. Introducing Adobe Bridge
      8m 41s
    6. The all-important file type associations
      3m 20s
    7. Navigating inside Bridge
      4m 23s
    8. Previewing and collecting
      5m 55s
    9. Using workspaces
      6m 41s
    10. Customizing a workspace
      6m 14s
    11. Cool Bridge tricks
      8m 17s
  3. 1h 4m
    1. Preferences, color settings, and workspaces
      35s
    2. Keyboard increments
      5m 12s
    3. Scratch disks
      3m 48s
    4. Changing the user interface and setting Appearance of Black
      4m 14s
    5. Best workflow color settings
      9m 17s
    6. Synchronizing settings across CS4
      3m 2s
    7. Working inside tabbed windows
      7m 6s
    8. Organizing palettes
      5m 4s
    9. Saving a custom workspace
      4m 12s
    10. Zooming and panning
      4m 19s
    11. Using the Zoom tool
      3m 3s
    12. Navigating the artboards
      5m 5s
    13. Nudging the screen image
      3m 3s
    14. Scroll-wheel tricks
      2m 8s
    15. Cycling between screen modes
      4m 35s
  4. 1h 22m
    1. The Wedjat (or Eye of Horus)
      55s
    2. The line tools
      2m 57s
    3. Introducing layers
      5m 10s
    4. Creating ruler guides
      6m 18s
    5. Creating custom guides
      5m 16s
    6. Snap-to points
      5m 25s
    7. Organizing guides
      5m 44s
    8. Making a tracing template
      3m 42s
    9. Drawing a line segment
      4m 29s
    10. Drawing a continuous arc
      5m 28s
    11. Drawing a looping spiral
      6m 5s
    12. Cutting lines with the Scissors tool
      6m 20s
    13. Joining open paths
      7m 31s
    14. Aligning and joining points
      6m 34s
    15. Drawing concentric circles
      4m 41s
    16. Cleaning up overlapping segments
      5m 34s
  5. 1h 4m
    1. The anatomy of a shape
      1m 1s
    2. Meet the shape tools
      3m 5s
    3. The traceable Tonalpohualli
      2m 52s
    4. Drawing circles
      4m 38s
    5. Enhanced Smart Guides
      4m 1s
    6. Aligning to a key object
      4m 29s
    7. Creating polygons and stars
      5m 4s
    8. Using the Measure tool
      3m 47s
    9. The Select Similar and Arrange commands
      3m 56s
    10. Rectangles and rounded rectangles
      6m 8s
    11. The amazing constraint axes
      5m 26s
    12. Grouping and ungrouping
      3m 35s
    13. Flipping and duplicating
      4m 12s
    14. Combining simple shapes into complex ones
      5m 24s
    15. Cutting and connecting with Scissors and Join
      3m 31s
    16. Tilde-key goofiness
      2m 53s
  6. 1h 41m
    1. The ingredients of life
      54s
    2. Fill and Stroke settings
      4m 22s
    3. Transparency grid and paper color
      5m 47s
    4. The None attribute
      5m 4s
    5. Color libraries and sliders
      3m 39s
    6. Industry-standard colors
      4m 38s
    7. Using CMYK for commercial output
      6m 39s
    8. Using RGB for the web
      7m 23s
    9. Color palette tips and tricks
      7m 18s
    10. Creating and saving color swatches
      4m 35s
    11. Trapping gaps with rich blacks
      6m 46s
    12. Filling and stacking shapes
      5m 39s
    13. Dragging and dropping swatches
      5m 0s
    14. Paste in Front, Paste in Back
      4m 54s
    15. Filling shapes inside groups
      5m 28s
    16. Pasting between layers
      4m 41s
    17. Joins, caps, and dashes
      6m 50s
    18. Fixing strokes and isolating edits
      7m 12s
    19. Creating a pattern fill
      4m 57s
  7. 1h 50m
    1. The power of transformations
      1m 20s
    2. From primitive to polished art
      2m 42s
    3. Using the Blob brush
      5m 46s
    4. Resizing the brush and erasing
      4m 15s
    5. Selection limits and methods of merging
      6m 39s
    6. Cloning and auto-duplicating
      6m 45s
    7. Customizing keyboard shortcuts
      3m 7s
    8. Moving by the numbers
      5m 15s
    9. Using the Reshape tool
      7m 47s
    10. Modifying, aligning, and uniting paths
      7m 14s
    11. Using the Offset Path command
      4m 43s
    12. Styling and eyedropping
      5m 29s
    13. Making a black-and-white template
      2m 27s
    14. Scale and clone
      4m 57s
    15. Enlarge and stack
      5m 46s
    16. Positioning the origin point
      6m 59s
    17. Using the Rotate tool
      3m 55s
    18. Using the Reflect tool
      4m 15s
    19. Series rotation (aka power duplication)
      6m 48s
    20. Rotating by the numbers
      6m 12s
    21. Transforming the tile patterns
      7m 52s
  8. 2h 4m
    1. Next-generation text wrangling
      55s
    2. Placing a text document
      5m 38s
    3. Creating a new text block
      6m 1s
    4. Working with point text
      3m 57s
    5. Selecting the perfect typeface
      5m 44s
    6. Scaling and positioning type
      8m 57s
    7. Leading, tracking, and lots of shortcuts
      5m 54s
    8. Adjusting pair kerning
      6m 55s
    9. Eyedropping formatting attributes
      3m 54s
    10. Flowing text from one block to another
      8m 28s
    11. Creating and applying a paragraph style
      7m 39s
    12. Rendering the text in graphite
      5m 55s
    13. Creating a scribbly drop shadow
      5m 17s
    14. Advanced formatting and bullets
      7m 43s
    15. Setting Area Type options
      4m 57s
    16. Justification and the Every-line Composer
      5m 52s
    17. OpenType and ligatures
      7m 19s
    18. Fractions, numerals, and ordinals
      9m 7s
    19. Swashes and small caps
      5m 40s
    20. The amazing Glyphs palette
      8m 12s
  9. 1h 18m
    1. Points are boys, handles are girls
      1m 20s
    2. Placing an image as a tracing template
      6m 56s
    3. Drawing a straight-sided path
      6m 8s
    4. Moving, adding, and deleting points
      6m 50s
    5. Drawing spline curves with Round Corners
      9m 7s
    6. Smooth points and Bézier curves
      8m 29s
    7. Defining a cusp between two curves
      6m 59s
    8. Replicating and reshaping segments
      8m 31s
    9. Converting anchor points
      7m 55s
    10. Deleting stray anchor points
      5m 1s
    11. Separating and closing paths
      5m 43s
    12. Eyedropping template colors
      5m 55s
  10. 1h 40m
    1. Paths never rest
      1m 34s
    2. Exploring the Appearance palette
      9m 54s
    3. Snip and Spin
      8m 3s
    4. Adding a center point
      4m 12s
    5. Keeping shape intersections
      3m 42s
    6. Lifting fills and selecting through shapes
      5m 54s
    7. Saving and recalling selections
      6m 20s
    8. Rotating is a circular operation
      8m 32s
    9. Lassoing and scaling points
      5m 28s
    10. Using the Transform Each command
      4m 11s
    11. Using the Magic Wand tool
      8m 1s
    12. Eyedropping live effects
      9m 58s
    13. Merging strokes with a compound path
      6m 50s
    14. Selecting and scaling independent segments
      7m 59s
    15. Scalloped edges with Pucker & Bloat
      5m 16s
    16. Expand before you merge
      4m 17s
  11. 1h 26m
    1. The new pleasures of printing
      44s
    2. Outlines and artboards in CS4
      7m 35s
    3. Setting trim size and bleed
      7m 17s
    4. Creating custom dynamic crop marks
      3m 41s
    5. Working with the Separations Preview palette
      7m 42s
    6. Trapping an object with an overprint stroke
      8m 20s
    7. Placing multiple artboards into InDesign
      5m 17s
    8. Working with the Print Tiling tool
      4m 56s
    9. Setting the General Print options
      6m 9s
    10. Setting printer marks
      5m 16s
    11. PostScript-only output and graphics
      9m 10s
    12. The Color Management options
      6m 56s
    13. Adjusting the Flattener settings
      7m 32s
    14. Setting the Raster Effects resolution
      5m 33s
  12. 1h 32m
    1. Illustrator does pixels
      51s
    2. Illustrator, PDF, and Save As formats
      8m 15s
    3. Saving an illustration for the web
      6m 13s
    4. Saving a continuous-tone JPEG image
      10m 2s
    5. Saving a high-contrast GIF graphic
      6m 27s
    6. The versatile PNG format
      4m 45s
    7. Saving a scaleable Flash (SWF) graphic
      11m 0s
    8. Opening and placing an Illustrator file in Photoshop
      12m 44s
    9. Exporting a layered PSD from Illustrator
      12m 57s
    10. Exporting to Microsoft Office and PowerPoint
      7m 24s
    11. Sharing with InDesign, Flash, and Photoshop
      12m 12s
  13. 1m 4s
    1. Until next time
      1m 4s

Start your free trial now, and begin learning software, business and creative skills—anytime, anywhere—with video instruction from recognized industry experts.

Start Your Free Trial Now
please wait ...
Watch the Online Video Course Illustrator CS4 One-on-One: Fundamentals
16h 48m Beginner Feb 06, 2009

Viewers: in countries Watching now:

Adobe Illustrator has long been a popular vector–based drawing program, but for many the learning curve is steep. In Illustrator CS4 One-on-One: Fundamentals, author and leading industry expert Deke McClelland shows users how to get in to the Illustrator mindset and overcome this learning curve. He covers the application's key features in a new way, making it simple and easy to master Illustrator. Deke teaches viewers how to use the core drawing and shape tools, the transformation and reshaping features, text, and the Pen tool. He also explains how to export and print. Even if learning Illustrator has been a struggle in the past, this training can help make sense of it. Exercise files accompany the course.

Topics include:
  • Creating continuous arcs and looping spirals
  • Building with geometric shapes
  • Selecting, placing, and scaling type
  • Creating spine curves with round corners
  • Using the new Blob brush to quickly draw and merge paths
  • Working with flattener and raster effects
  • Saving illustrations for the web
Subject:
Design
Software:
Illustrator
Author:
Deke McClelland

Trapping an object with an overprint stroke

In this exercise, I'm going to show you how to create a trap in Illustrator using an overprinting stroke. Now the technique itself is very easy. You create a stroke and overprint it. That's all there is to it. However, conceptually it's difficult because you need to know when and why you need a trap in the first place. Most folks, even those folks who have been working in the business for years who know what trapping is, most of them don't know when you actually need a trap. So I want you to be one of the people who does know this, because it's very important. Most of the time, you don't need to worry about trapping, but sometimes you do and when you do, you really do. So I'm going to demonstrate that in this document. I have gone ahead and saved my progress so far as Overprint document.ai found inside the 11_ printing folder and I'm going to move my Separations Preview palette down here.

Now you may recall this text right here, set in this spot color Pantone 200 C at this point of time. It has this big thick white stroke and let's say we don't want to have any white strokes. Now if we do have a big white stroke, we don't need to worry about trapping at all, because what we are trying to account for with trapping is a misregistration of plates that results in a little bit of a white gap, a paper colored gap, between different inks. We are asking for a big thick paper colored gap, so we wouldn't have anything to worry about in this case. It's only if that stroke were to go away that we would have problems. So I'll go ahead and click on this text to select it and then I'll go up to the Control panel and change the Stroke to None.

Now if we were to have a little bit of misregistration between the spot color plate and the other inks, the Cyan, Magenta, Yellow and Black plates, then we would end up with these tiny little hairline white gaps that would be complete giveaways of our bad printing job. And that's not something we want. So I'm going to press Ctrl+Shift+A, Command+ Shift+A on the Mac to deselect that text. Now let's start with a scenario that does not require trapping. When you are working with process color inks and you are doing a lot of sharing, in other words, two neighboring objects share some Magenta or they share some Yellow or they share some Black or they share some Cyan, what have you, then you don't need to worry about trapping, it's when they don't share inks in common that you have problem.

So let's look at the first scenario where you don't have a problem. I'm going to go over here to the Swatches palette and I'm going to take this color right here, this Pantone 200 C that we just got done converting to a spot color, I'm going to convert it back to a process color by double-clicking on it and I'm going to change the color type from Spot Color to Process Color, like so and notice what it's made up of here 0, 100, 63, 12. So we are not going to have anything going on in Cyan, but we are going to have a lot going on in Magenta, Yellow, and a little bit going on in Black. Click OK. Now it shouldn't change on screen. It should look exactly the same on screen, except for Separations Preview palette, which just lost the color. So our Pantone 200 C color went away because we don't have it anymore, we are not coloring for it inside of this document any longer.

All right, let's take a look at the various plates however. I'm going to start by Alt clicking or Option clicking on the eyeball, in front of the Cyan ink. Now in this case we have got a big knock -out, right. We have got a solid color background essentially, a solid Cyan with a white knock-out right here. Which means that where the Cyan ink is concerned, where the Cyan plate is concerned, we would definitely need some kind of trapping because we have no coverage here, something could go wrong. All right, but that's just one plate. We have got four plates to work with here.

So go ahead and turn on Magenta and turn off Cyan and now we have got ink sharing, we have full coverage inside the letters in the Magenta plate and we have got light coverage in the background. This is enough to prevent us from having to worry about trapping. Just this one plate by itself is enough. So let's see what we have going on in yellow as well. Turn on Yellow, turn off Magenta. They are getting to be identical, they are not almost identical but we have solid coverage of Yellow In the background and we have 63%coverage of Yellow inside the letters. So they are only 40%off from each other. That's perfectly fine. That eliminates the need for any trapping as well. Turn on Black and turn off Yellow, it's almost uniform. Those are almost identical colors, there in Black.

So in other words, between Black, Yellow and Magenta, we have all the ink sharing that we need. We do not need to worry about gaps. We are not going to get them. We are not going to get white gaps there, because everything is getting filled in and we do not need to worry about trapping around these letters. The fact that's Cyan in the mix, who cares? It's not going to cause any problems for us whatsoever. All right, so let's compare this to working with a spot color. Spot colors almost always demand traps, because they are always knocking things out. I'm going to go back to the Swatches palette, double-click on that Pantone 200 C guy. Let's just change it back to spot color and then click OK. Now let's see where the difference is noticed. That the Separations Preview palette went ahead and added back in Pantone 200 C. Let's go ahead and see the difference.

Now, if I turn off just Pantone 200 C, just turn off that one by clicking on that eyeball. Big massive knockout. I'm knocking out the Cyan plate, I'm knocking out the Magenta plate, I'm knocking out the Yellow plate and I'm knocking out the black plate. So solid knockouts across the board, this guy is quite the boxer, he however is leaving the opportunity for gaps around the letters that's a bad thing so we need to do some trapping and here is how it works. Go ahead and turn back on Pantone 200 C so that you can see that text. Once again click on it to select it. And then I want you to go up to the Stroke item here in the Control palette once again and click on it and set it to that spot color.

You can see that's the spot color because it has a little dot in its white triangle. That's our guy, go ahead and click on it, in order to assign the same color that we are using for the Fill to the Stroke. And in my case, the stroke is set to one point, which is fine, I'm going to raise it really high to four point for a second, which is completely insane, where trapping is concerned but I want you to see what's going on. All right, now this by itself doesn't solve our problem at all. All we are doing is shifting the red outward and we are shifting the knockout outward as well. So if I were to turn off Pantone 200 C, you can see that we have just got a bigger knockout. So we haven't accomplished anything. Turn it back on, then you want to bring up that Attributes palette again, it's this guy right there and you could also choose Attributes from the Window menu and then turn on Overprint Stroke.

Now because Overprint Preview is turned on, we can see the effects of overprinting. Let's go ahead and put the Attribute palettes away because we are done with it. We do not, by the way, want to overprint the Fill that will create this effect here. That would just fill in the letters. We don't want that. Just the Stroke. All right, go ahead and put that guy away and notice what we have got is a smaller knockout. So this is what the knock-out looks like now, it looks like original letters without the stroke and this is what the Pantone 200 C plate adds, it adds a thicker bunch of letters right here and then it's definitely going to fill in the gap. So if we have any misregistration between the plates, this extra trap here, which is the Stroke itself, is going to fill in the gaps quite nicely. Now the only thing is that also looks terrible.

We have got this big ginormous strokes around all of our texts. We don't want that. So we want to make the stroke as thin as it can be. And here is what I'm going to tell you, by way of advice. If you are working with a cheap consumer print house, then you might want the stroke to be as high as one point in order to make sure to fill in the gaps. Now you shouldn't see such a pronounced tracing affect as this when you actually up with the document but you will see a little bit of tracing when you have such a high stroke value. If you are working with the real top-of-the-line, commercial print house, you know a big one that really takes their job seriously, then you can take this value down to 0.5 points as a Stroke or you can even talk to your print house and see what they recommend.

They may say no, ma'am. You know we can do a Hairline stroke, we can do a 0.3 ,no problem, and we will hold that for you, we guarantee it. That kind of thing. So just check with your people, talk to them. Anyway, this is how you make a trap and bear in mind, I just want to make this clear in case it's not, you never need to trap when you are printing a local composite job. In other words, when you are printing it to your personal ink-jet printer, trapping is never required. Because you can't really do a spot color. hat's not an issue. So you are always mixing inks together; it's only when you are preparing a job for commercial reproduction.

In the next exercise, I'm going to show you how to take one of these illustrations here and print it from inside a page layout program such as InDesign. Stay tuned.

Find answers to the most frequently asked questions about Illustrator CS4 One-on-One: Fundamentals .


Expand all | Collapse all
please wait ...
Q: Adobe Bridge CS4 is not previewing files in the same way for me as it is in the tutorial. All I am seeing is a low-quality thumbnail of the image, not previews of each artboard.  Why is there a difference between the tutorial and what I am seeing?
A: There is a different view in the tutorial because the author used a beta version of Bridge during the recording. The final release of Bridge CS4 displays thumbnails as you describe.
 
Share a link to this course

What are exercise files?

Exercise files are the same files the author uses in the course. Save time by downloading the author's files instead of setting up your own files, and learn by following along with the instructor.

Can I take this course without the exercise files?

Yes! If you decide you would like the exercise files later, you can upgrade to a premium account any time.

Become a member Download sample files See plans and pricing

Please wait... please wait ...
Upgrade to get access to exercise files.

Exercise files video

How to use exercise files.

Learn by watching, listening, and doing, Exercise files are the same files the author uses in the course, so you can download them and follow along Premium memberships include access to all exercise files in the library.


Exercise files

Exercise files video

How to use exercise files.

For additional information on downloading and using exercise files, watch our instructional video or read the instructions in the FAQ .

This course includes free exercise files, so you can practice while you watch the course. To access all the exercise files in our library, become a Premium Member.

Join now Already a member? Log in

* Estimated file size

Are you sure you want to mark all the videos in this course as unwatched?

This will not affect your course history, your reports, or your certificates of completion for this course.


Mark all as unwatched Cancel

Congratulations

You have completed Illustrator CS4 One-on-One: Fundamentals.

Return to your organization's learning portal to continue training, or close this page.


OK
Become a member to add this course to a playlist

Join today and get unlimited access to the entire library of video courses—and create as many playlists as you like.

Get started

Already a member ?

Exercise files

Learn by watching, listening, and doing! Exercise files are the same files the author uses in the course, so you can download them and follow along. Exercise files are available with all Premium memberships. Learn more

Get started

Already a Premium member?

Exercise files video

How to use exercise files.

Ask a question

Thanks for contacting us.
You’ll hear from our Customer Service team within 24 hours.

Please enter the text shown below:

The classic layout automatically defaults to the latest Flash Player.

To choose a different player, hold the cursor over your name at the top right of any lynda.com page and choose Site preferences from the dropdown menu.

Continue to classic layout Stay on new layout
Exercise files

Access exercise files from a button right under the course name.

Mark videos as unwatched

Remove icons showing you already watched videos if you want to start over.

Control your viewing experience

Make the video wide, narrow, full-screen, or pop the player out of the page into its own window.

Interactive transcripts

Click on text in the transcript to jump to that spot in the video. As the video plays, the relevant spot in the transcript will be highlighted.

Learn more, save more. Upgrade today!

Get our Annual Premium Membership at our best savings yet.

Upgrade to our Annual Premium Membership today and get even more value from your lynda.com subscription:

“In a way, I feel like you are rooting for me. Like you are really invested in my experience, and want me to get as much out of these courses as possible this is the best place to start on your journey to learning new material.”— Nadine H.

Thanks for signing up.

We’ll send you a confirmation email shortly.


Sign up and receive emails about lynda.com and our online training library:

Here’s our privacy policy with more details about how we handle your information.

Keep up with news, tips, and latest courses with emails from lynda.com.

Sign up and receive emails about lynda.com and our online training library:

Here’s our privacy policy with more details about how we handle your information.

   
submit Lightbox submit clicked
Terms and conditions of use

We've updated our terms and conditions (now called terms of service).Go
Review and accept our updated terms of service.