Ok, so we’ve output our pIllusion footage and are ready to bring the 5 image sequences into our After Effects rocket project. From this point on, we are going to be working in AE, so unless I indicate otherwise, all actions from here on in will be don in AE, not pIllusion. Let’s get started:
1. Go to the File menu and click “Import Multiple Files.” This will bring a dialog to import your files.
2. Navigate to your “Smoke_Mask” folder and highlight the first file, “Smoke_Mask0001.jpg.”
3. Select the “JPEG Sequence” option box.
4. Click Open – the first file will now be imported, and the dialog will blink for a moment indicating that you should pick your next file. Notice that the “Cancel” button has now become the “Done” button.
Do the same for the 2 other JPEG sequences – “Flame” and “Smoke.” For the TIFF Sequences (The Asteroids), we’ll need to do something slightly different. With the import dialog still open (or reopen it if you accidentally clicked done):
1. Navigate to your “Asteroids_Front” folder and highlight the first file, “Asteroids_Front0001.tif.”
2. Select the “TIFF Sequence” option box.
3. Click Open - An “Interpret Footage” Dialog will now open – After Effects has detected the Alpha Channel, but is not sure what to do with it.
4. Choose the “Straight” option. (If you recall, we chose to remove black background from our RGB channels when we exported these files.)
5. Click OK.
6. Repeat the process for the “Asteroids_Back” sequence.
7. When you have imported all 5 sequences, click “Done.”
In the Project Window, your new footage should look like a series of cards placed on top of the other. If all they show is one card, that means that AE only imported the first frame, instead of the entire series of images. This probably happened because you forgot to click on “JPEG Sequence” or “TIFF Sequence” while in the import dialog. You’ll have to delete the footage, and re-import it correctly.
OK, I need to be upfront with you about this. When we were importing position data, we made a mistake in calculating where our emitters needed to be. We didn’t take certain things into consideration, and now we have to fix a few things. You see, in After Effects, an object’s position (as well as rotation) is based on its anchor point (or center/pivot point). That means that the emitter’s we set up are following the center of the rocket image, not the back of it where all of that smoke and fire would be shooting out of. Fortunately, all of this was taken into consideration before this was written, and it will be easy to fix by starting the animations of our exhaust particles a little late (so that they will be behind the rocket by a few frames, and therefore coming out of the tale engine, instead of the middle).
Before we jump into the solution we will be using, I just want to mention that you can avoid this sort of thing by moving the image’s anchor point to wherever you would want to set up your emitter. The downside of that solution is that it effects the rest of the objects transformations so that it would pivot on the engine (back), instead of the center. Another solution is to create a dummy object for the emitter to follow. It may be your best bet in some cases, but in this project, we don’t need to do that.
We’re now going to set up our layers in After Effects. This is the order they should be in when we are done is (from top to bottom):
1. Asteroids_Front
2. Rocket
3. Flame
4. Smoke_Mask
5. Smoke
6. Asteroids_Back
7. Space_BG
Rocket and Space_BG are already in there, and we are going to have to add layers in front of and behind the rocket. Lets start dropping our layers in.
1. Make sure your project is at the first frame. Use the time slider (Timeline window) or the Time Controls to do this.
Above: Time Slider in Timeline window
Below: Time Controls
2. In the Project Window grab hold of the footage called “Asteroids_Front” with your mouse by Left+Clicking on it – Don’t let go!
2. Drag “Asteroids_Front” into the Timeline Window – again, don’t let go yet!
3. Notice that in the Timeline Window a black line appears where your footage will be placed. Drop this footage at the very top of the layers, so that it is now the top layer. All you have to do is let go of the left mouse button, and the footage will be inserted.
Just so you know, you can always reorder your layers by grabbing them with the mouse and moving them up or down. Just make sure you grab them by their name, and NOT by the colored line which indicated their time position.
4. Do the same thing for “Asteroids_Back” but this time, put it between the layers called “Rocket” and “Space_BG.”
Next we are going to drop in the Flame:
1. Move to Frame #1 (That’s the second frame – in AE, the first frame is Frame #0).
2. Using the method described above, drop the flame footage right behind the rocket, and above “Asteroids_Back.”
Wait a sec! What just happened? The background image
and the “Asteroid_Back” layer just disappeared. This is what you probably
see:
That’s exactly what you should see, because we haven’t told AE how to use this layer – right now, it is reading it as a normal layer, but we want to set it up so that only the light parts of this image (flame) show through while the dark parts (Black BG) are not seen. To make this happen, we need to change our layer transfer mode from “Normal” to “Screen.”
1. In your timeline window, you should have a section called “Switches/Modes.” The “Modes” section may be hidden because It shares the same space as the “Switches” section.
2.
Just click on the words Switches/Modes below the section to jump between the 2
views. Once you are in the “Modes” view click on the word “Normal” and
from the pop-up select “Screen.” If you use Photoshop, chances are
that the concept of layer transfer modes aren’t new to you.
You should now be able to through the layer. If you move through your animation, you’ll see that your flame is visible, even though the black background is not.
Next we are going to add in the smoke, and the smoke mask:
1. Go to Frame #3 in the timeline.
2. Bring both “Smoke_Mask” and “Smoke” into the timeline window, so that “Smoke_Mask” is above “Smoke,” and both are below the layer called “Flame.” If it is starting to get confusing, just refer back to the order of layers I mentioned at the beginning of this section.
Again you’ll see that the BG footage has been blocked out by your new layers. This time however, we are not going to use Layer Transfer Modes. Instead, we are going to set up a mask for the smoke.
3. Select the layer called “Smoke.” You can do this by clicking on the layer name.
4. In the Modes section, next to the layer
transfer mode pull-down is the Track Matte pull-down. Click on it and choose
“Luma Matte” – Actually it will say something like “Luma
Matte[Smoke_Mask0001-0100.jpg]” – but Luma Matte is what is important.
Now, the black BG is gone, and if you jump through your animation, you’ll see that there is both smoke and fire coming out of your rocket ship, and that some of the asteroids are behind the smoke, and some are in front of the ship.
If you have your timeline window selected and hit the “0” key on the number pad, After Effects will start making a Ram Preview – it may take a while for it to cue it up, so be patient. Also, it may not be able to show the whole animation since the RAM preview is dependant on how much memory you have available. Since it’s not a long animation, so chances are you have enough, but depending on what you have running in the BG, you might not. There are ways to set up your projects so that RAM previews take up less RAM (such as lowering the resolution and size of the preview), but that is outside the scope of this tutorial. There is plenty of info on this in the AE help files.
Well, that’s pretty much it for parts 1 and 2. Save your work, and then go ahead and render your final movie. Feel free to go back and play with the different layer transfer modes to see how your particles are effected. Just remember, there’s no exact way to do this – For example, you don’t always have to use smoke the way we did in the tutorial. You can also use “Screen” or “Lighten” or any of several other Layer Transfer modes depending on the look you want. What we did here was demonstrate several different ways in which you can effectively use particleIllusion footage in After Effects. While pIllusion may be external to After Effects (as opposed to some AE plug-ins), as you can see, it is still going to be your fastest 2D particle solution, hands down.
But wait! There's more! As we mentioned earlier, for the last part of the PI AE tutorial, we are going to give you the opportunity to blow up a planet, and learn something in the process - and it's not nuclear fusion. In the next (and last) section, we're going to make soft-edged particles with an alpha channel work in After Effects. We've separated this section from the rest of the tutorial because soft-edged particles with an Alpha Channel only work in certain cases.
We highly recommend you continue on to the next part - it will almost definitely come in handy, and save you a lot of trouble later. Also, YOU GET TO BLOW UP A PLANET!!!!!!!!!
Click here for the next part...