Start learning with our library of video tutorials taught by experts. Get started
Viewers: in countries Watching now:
In After Effects CS5 Essential Training, author Chad Perkins discusses the basic tools, effects, and need-to-know techniques in Adobe After Effects CS5, the professional standard for motion graphics, compositing, and visual effects for video. The course provides an overview of the entire workflow, from import to export, as well as detailed coverage of each stage, including animating text and artwork, adding effects to compositions, working in 3D, and rendering and compressing footage. Exercise files are included with the course.
Now we're continuing where we left off here. So, I want to show you this little quick tip that you can actually modify expressions to suit your needs. So, we have this expression already where the right wheel is connected to the left wheel via this expression. But let's say, for example, that we want the right wheel to spin twice as fast as the layer on the left. So, what I'm going to do is actually take this to 0, click the stopwatch for Rotation, and we'll go out in time about 3 seconds, and we'll rotate this a certain amount.
We'll go ahead and press the letter N to set the end of the work area because it's over 8 seconds long. We really don't need that much extra time. So, what I'm going to do is click inside of the expression. As you can see, they're both rotating now. I'm going to click inside this expression and I'm going to click on the end of the expression and put our cursor there and I'm going to type *2. And what that's going to do is it's going to say okay, take this value, whatever the left wheel rotation value is, and multiply that by 2. So, if we click outside to accept that, we'll now see that the wheel on the right is spinning twice as fast as the wheel on the left is and to prove that, you can see when we stop it that the initial value is 166.4, and the right wheel is double of that, 332.7. And actually, if we were to click in here, we see that this is actually a little bit more descriptive, four decimal places, 166.3556, and then we have basically 0 here, but it's rounding up to 332.7.
The reason why this right wheel rotation shows 0 when we click on it is because it didn't have a value of its own before we create the expression. So, what we're seeing right now is the expression, but it really has a value of 0 on its own. But anyways, this is where I wanted to get to is that we can adjust expressions by just putting a little mathematical equation at the end. If we wanted this to rotate in the opposite direction, we can multiply this times -1, and then as we rotate, you can see that they are rotating in different directions now. And all of the mathematical functions, add, subtract, multiply, and divide, all work and you can access those via numeric keypad, so I can divide by 2.
Now when I preview this, the right one goes half as fast as the one on the left. So, if you need to do some light modifications to an expression, it's just that easy.
Find answers to the most frequently asked questions about After Effects CS5 Essential Training.
Here are the FAQs that matched your search "":
Sorry, there are no matches for your search ""—to search again, type in another word or phrase and click search.
Access exercise files from a button right under the course name.
Search within course videos and transcripts, and jump right to the results.
Remove icons showing you already watched videos if you want to start over.
Make the video wide, narrow, full-screen, or pop the player out of the page into its own window.
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.