CAP 151 -
Introduction to Computer Animation
Lesson 2 - Advanced Animation (part 1)
This lesson introduces more features of the After Effects interface. Objectives important to
- Adobe Bridge
- Graph Editor
- Value graphs and Speed graphs
- Motion paths
- Smoothing paths
- Auto-Orient and Motion Blur
We begin this lesson by clarifying some concepts.
- Keyframes hold values for their layers at a moment on the timeline.
- Keyframes also hold interpolation values: the rate at which a value changes before and after the keyframe (velocity), and the smoothness or abruptness of the change into and out of the keyframe (influence).
- Keyframes can be temporal, showing a value changing over time, and they can be spatial, showing a change in position over time.
The text introduces Adobe Bridge, a file browsing program program that seems to have little purpose. It used to give you access to Adobe Stock Photos, as the text explains, but that service no longer exists. It still gives you access to thumbnail images of your source files (stills, videos, etc.), and it provides a common interface for this service for all applications in Adobe's Creative Suite. It allows you to rate your source material with stars and with color codes. This may be useful for media that you are using for a particular project, but it seems like a lot of work, adding short lived notes to the source files that may be meaningless when you change projects. If you have a need for such things, great. Otherwise, that's what folders were invented for.
Tutorial Notes and Questions
Note: Exercises should be carried out in the classroom. You will not get very much out of them by just reading, nor will you learn what is required by just experimenting on your own. Each exercise is meant to cover specific content that you will be required to know.
Work through the exercises and turn in your answers to all questions below as part of the homework for this assignment.
Tutorial 1 (Adobe Bridge):
- Start After Effects. Start Adobe Bridge by clicking File, Browse. Examine the Adobe Bridge interface.
- As noted above, Adobe Stock Photos is no longer available.
- Use the Folders tab as instructed. Navigate to your copy of the lesson files.
- Note how you can preview still images and videos in the Adobe Bridge interface.
- A useful feature, the thumbnail views of the files can be sized.
Question 1: How big can you make the thumbnail file images?
- Note the Label menu features that let you tag the files with stars and colors.
- Explore the filtered display feature to show only files with specific labels or ranges of stars. The end of the tutorial tells you to import a file into After Effects.
Question 2: Which of the three described methods works in our classroom?
The next section of the lesson takes us to the Graph Editor, and introduces several useful commands.
Tutorial 2 (Graph Editor):
- Start After Effects. Click File, Browse Template Projects. Adobe Bridge will open and show you the templates. Note: the text tells us that the trial version of After Effects does not include the templates. If you are using the trial version at home, you do not have the templates for this tutorial.
- You should be able to browse several projects.
- Open the indicated project. Tell After Effects not to save the "current project".
- You are told to select the timeline, then select all layers of the current project.
Question 3: What is the keyboard command to select all layers? What is the command to show all properties that have animation?
You are also told to perform a RAM Preview of the current animation. You will use the command to do this several times in this lesson.
Question 4: What is the command to do a RAM Preview?
- Find and click the Graph Editor button. Continue following the instructions in this step,
- Step 6 tells you to click the time display and move to 1.10. This could use some explanation. 1.10 in this context means "1 second and 10 frames". Remember that we are running at 29.97 frames per second, so this means about 1 and a third seconds into the comp. This seems like an odd way to reference time, but it is kind of like using feet and inches to measure distance.
The rest of the paragraph uses semi-colon notation, such as 1;10 to mean 1 second and 10 frames. See page 56 for an explanation of the semi-colon (Drop Frame), colon (Non-Drop Frame), and other notations.
Non-Drop Frame notation numbers 30 frames per second, which gets out of synch with the actual rate after a significant number of frames. The text recommends using this system only if your production runs under a half hour.
Drop Frame notation starts out the same, but does not use frame numbers 00 or 01 for any second that ends a minute, unless the minute number is divisible by 10. (Starts to sound like how you calculate leap years, for similar reasons.) Note that this does not mean frames are lost, it only means that we do not use some frame numbers in most minutes.
The text also refers to a sidebar on page 40 in this step. You will learn that there are three ways to zoom and pan on the timeline. Use whichever is convenient when you want to do so.
- If you have followed the steps so far, you should see a screen similar to the picture on page 40. Note, as stated in the text, that you can see graph lines for the animation of different layers by selecting those layers. The lines are color coded for the kind of animation. In this step, you learn that turquoise stands for rotation. You are told to drag the yellow square at the end of the rotation graph line.
Question 5: Which directions can you drag the square to change its value?
Question 6: Which directions can you drag the square to change when the rotation ends?
- This step shows the use of the Easy Ease In button (by Susie Homemaker?) to adjust the velocity and influence of the keyframe. It changes the slope of the line leading into the keyframe, making the rotation slow down before it stops. The line does not taper, its slope does, making it a curve. The line becomes more like a parabola. The keyframe changes by having a Bezier handle added, which lets you manually adjust the slope of the curve.
- This step tells us that the red line on the layer's graph stands for scale. Practice editing the scale as indicated. Note the Undo command at the end of the step: the standard Windows shortcut, Ctrl-Z.
- Step 10 takes us to more smoothing. It explains that we don't want to use linear keyframes for our scale changes, because the changes are too abrupt. One way to change a frame to a smooth frame (Auto-Bezier frame) is to Alt-click it. Alt-clicking the frame again changes it back. When not in the Graph Editor, linear keyframes are diamonds, and Auto-Bezier keyframes are circles.
- Step 11 finishes the tutorial, suggesting that you change two other layers before you are done
The text continues with a tutorial about drawing and smoothing a motion path.
Tutorial 3 (Float Like a Butterfly, part 1):
- We will start this tutorial, and save it at the end of page 47. We will continue with it next week.
Open the file indicated for this tutorial.
- Select the butterfly layer and show its scale animation.
Question 7: What is the hot key to show scale for the selected layer?
- Change the Workspace as instructed.
- You should now have a Motion Sketch panel. This will let you draw motion with your mouse, while After Effects automatically saves keyframes for you.
- You are cautioned to practice drawing a motion path before actually drawing it, to get a timing for your motion that will fit in the desired timeline (5 seconds, in this case). Click the Start Capture button to begin capturing the motion path.
Question 8: What do you do after clicking the Start Capture button to actually begin the motion path?
Question 9: What actually ends the motion capture sequence?
RAM preview your path, and use Undo if necessary to begin the process again. Your path should not be identical to the one the author's chose. Try to make it better.
Save your project before continuing.
- No matter how well you drew your path, it will need to be smoothed. Access the Smoother Panel as instructed. It automates making the path smoother than your hand drawn motions made it. Use the Tolerance value to keep more or less of your detail for the path. Note: we may find the Smoother as part of the Motion Sketch panel, if we are using CS3 in the classroom.
- As noted in the text, the butterfly does not rotate on the path yet. This step reviews two ways to fix this:
Finally, use the Motion Blur feature as instructed. You may find that you like or dislike it.
- Use Ctrl-Alt-O to open Auto-Orientation, or
- Click Layer, Transform, Auto-Orient
In either case, edit the Bezier handles for the first and last frames as instructed, to avoid the twist the automated feature inserted.
Question 10: What is the procedure to change the the amount of blur in the effect?
Save the project at the end of page
47 as instructed.
Assignment 3b: From your Week 2 storyboard, create a simple animatic as demonstrated in class of your animated logo. Use some of the techniques from this week's lesson to refine the animation.