Setting keyframes for particle birth rate

- Now that we have our animated steam effect working,…now what we're gonna do is create some keyframes…to control the Birth Rate…so that we have a constant Birth Rate…over a certain amount of time.…This way, we can create an animation…that loops in the next movie.…So, with our solid selected in the timeline,…and in our Effect Controls panel,…let's come over here and open up the Particle System.…Let's come down here, let's close all these items up,…and up here next to Birth Rate, we'll see a stop watch.…This will allow us to add a keyframe…specifically for the Birth Rate property.…Now, before we click on this,…let's come down to the timeline.…

Let's bring the playhead back to zero.…With the playhead at the zero marker,…now let's come up here and click on the stopwatch.…The stopwatch will record a keyframe property,…and now, in the timeline panel,…you'll see the Effects properties in addition to Transform.…Let's close up Transform, let's open up Effects,…and here we'll see Particle Systems…and the Directional Blur.…