AETOONS: CARTOON ANIMATION IN AFTER EFFECTS

INTRODUCTION
SOFTWARE CHOICES
LEARNING FROM BURBANK
DIGITIZING DRAWINGS
SCANNING
CAPTURING WITH A CAMERA
STOP MOTION CAPTURE IN PREMIERE
STOP MOTION CAPTURE WITH FRAME THIEF
EQUIPMENT
FOLDERS
PHOTOSHOP RENDERING/LINES
PHOTOSHOP RENDERING/COLOR
DIGITAL COLOR
SETTING UP AFTER EFFECTS
PIXEL SHAPE?
PROJECT WINDOW
IMPORTING SEQUENCES
INTERPRET FOOTAGE
FILE TYPES
PS COMP
TIMELINE WINDOW
TIMELINE AS EXPOSURE SHEET
TIME REMAP
PENCIL TESTING
RAM PREVIEW
COMPOSITIONS
PRE-COMPING
LAYER WINDOW
COMP WINDOW
LAYER STRATEGIES
KEYFRAME : CUTOUT : COLLAGE
KF ACCELERATION
MOTION BLUR
MORE TO COME


INTRODUCTION
Using After Effects to produce cel animation is a specialized focus often overlooked in user manuals and other guides. These notes are an effort to fill that gap. They are for animation students who already grasp the basics of sequence drawing on paper and are familiar with After Effects (AE), Photoshop (PS) and Quicktime. Animators have always had to blend technology with artistic skills; now, as film is evolving (indeed “film” or “movie” here describe any time-based program on various media), we must learn to graft new technologies into our workflow.

These notes grew out of my experience as an independent animator making cartoons, experimental films and commercials. Migrating from analog to digital production methods has been liberating, tedious, and oddly circular: I started with a little movie camera on a homemade copystand, advanced to ever larger and heavier 35mm camera stands, until now, 30 years later, I am back to a little video camera on a copystand. The one constant has been the technique of sequence drawing on paper, often combined with collaged graphic and photo elements, and the imperative to try, test, mess with anything that might work. The most important change has been the replacement of the cinema apparatus -- film, camera, optical printer,
laboratory, mechanical projection -- by the digital apparatus--relatively cheap, rapidly evolving software and computers connected to digital video media.

“Cartoon” here implies a graphic look, intrinsically flat, related to drawing and painting (I do not discuss 3D or CGI animation); “cel” derives from transparent cellulose acetate sheets and implies a methodology based on 2D layering. Cartoons can be made in a wide diversity of innovative styles, not just “traditional” outline drawing with color fill. Except for FrameThief and Final Cut Pro, all the SW discussed is available on Mac and Windows, but the keyboard commands noted below are only for Mac.

SOFTWARE CHOICES
There are numerous omnibus applications (Retas, Toonz, Animo) in use today which handle all the functions of cel animation, from testing, scanning, painting, to compositing. They are organized for team productions which break down tasks for specialized workers, and many of the tools seem to be limited to conventional cartoon design concepts such as filling linear shapes. AETOONS is a flexible alternative to these expensive, turnkey systems because it is based on a medley of applications which are cheap, popular and constantly being upgraded. AE and PS are industry standards, supported by third party software, tutorials and user-forums.

A word of caution: AETOONS may just be my own elaborate rationalization for using popular programs which often aren’t always the perfect choice for a particular process. Once I learned a workaround it came to feel natural even though another program may have solved the problem more elegantly. For years Painter has had a superior set of brushes and media tools but I could never get used to its layering system, while PS has had, until now, mediocre brushes but a sophisticated and facile layering system. The former still offers enormous potential for creating straight-ahead, animation directly painted in the window and exported as a Quicktime--something PS still can’t do. It’s important to realize that files can be ported among paint programs for rendering, then layered and sequenced in AE.

If you feel comfortable drawing sequences directly on a digitizing tablet, not on paper, you can stop reading now and consider using Flash, ToonBoomStudio or Moho. They are vector-based paint/animation apps which can create very streamlined designs that play easily on the Web.

LEARNING FROM BURBANK
The most important precedent for understanding the process of digital cartoon production is traditional cel animation. The animator prepared sequences of drawings (cels) which comprised a scene. The drawings and cels were organized into layers to separate figure from ground, static from dynamic elements, then they were scripted with an exposure sheet to indicate a precise schedule of timing, leaving virtually nothing to chance in the camerawork. The animator needed to understand both drawing and camera processes

Today, AE animators control layering (compositing) and timing (sequencing) by using the Timeline Window, a temporal spreadsheet. Unlike film, video, and cel production AE is resolution and timeframe independent. You can set the size, format, and the frame rate of your animation to match your final medium. You can even mix and match these settings within a project, or change them in midstream.

Before the advent of computers animators were forced to reconcile the differences between film and video, each running at different playback speeds (24 and 30 fps), with different resolutions and having differing esthetics based on their respective media. AE now offers the proverbial third choice, the synthesis which absorbs previous technologies while allowing compatibility with whatever the future holds.


DIGITIZING DRAWINGS
There are three methods of digitizing drawings: scanning with a flatbed scanner, shooting with a video camera or shooting with a digital still camera (DSC). The first method can result in a higher resolution image but is slow; the second method, very similar to down-shooting on an animation stand, is fast but limited to video resolution; the third can yield high resolutions but the software for shooting is not yet sophisticated. If the final medium is film, requiring a resolution of 2000 pixels in width (2K), one and three are the preferred option; if video is the final medium option two may be ideal (see EQUIPMENT). Some animators scan at a higher resolution to retain a delicate line quality, then scale down in the composition. For those interested in retaining a textured, rough, or heavy line video rez may prove to be ideal. It is important to test and compare methodology on your presentation device.

For our purposes drawing quality has nothing to do with design or skill. It refers to the contrast between line and paper. If you use a wispy, thin, or gray line it will be difficult to separate the line from the paper. Try animating with ink (using brush or marker) or soft pencil; very light roughs in blue can be inked over and the blue can be erased or dropped out digitally. But if paper quality is part of the design, don’t worry about separation.

SCANNING
To save time, use stand-alone scanning software that allows you to scan directly to a folder, without having to reopen within PS. I usually scan at 720 X 540, 24 bit RGB, 72 DPI, and save using a traditional naming convention such as A.01, A.02 (letters representing layers). Of course you may also use a single word to identify the sequence but the numbering must be progressive and consistent. If you plan to zoom into the file sequence you will need to scale up proportionately (e.g. zooming from 12F to 6F would require a scanning resolution of 1440 X 1080 to avoid pixel chunks). You can set the scanning specs to achieve optimum contrast or adjust later in PS. If the scanning SW won’t let you set the actual size, only a percentage, do a test to make sure you won’t need to scale up in AE.

When you scan and paint in PS you will be working in a square pixel environment. That’s why you should use 720 X 540 or larger. When you import the file to AE, which recognizes both square and oblong pixels, you may notice a slight squeezing of the image, but it will expand on an NTSC monitor.

To preserve a particular quality of line you may scan and paint at higher resolution, then scale down in AE. But watch out! This strategy will result larger files and slower AE operations. There may be unintended artifacting in the scale-down, and the desired qualities may not even be noticed in the final composite NTSC video. When in doubt, test.

CAPTURING WITH A CAMERA
In the old days, Pencil Tests were shot on film with back lighting to make all levels of paper visible. Early video line testers used surveillance VCRs to record frame by frame. Today, the Video Lunchbox can record frames into memory for playback to videotape. But the hardware is expensive and the video quality is sufficient only for testing because it captures only one, not both fields of video. So, my advice is use it at school, but don’t buy it.

Capture with software usually offers a variety of choices which you should decide before you start. Most important, are you capturing for a test or for your final production? Is your sequencing being fixed at capture, or will it be ordered later in AE? If your sequence is a cycle you can just capture it once, then loop it on playback. The rate can be programmed during sequencing so it will automatically capture one, two or more frames at every keystroke. If you have an inconsistent rate, perhaps with holds, and you are NOT recording final design art, you may elect to record your sequence exactly like your exposure sheet, capturing your whole scene of various sequences and holds as one shot. You can even play the scene back in sync with a soundtrack.

For final captures you must capture only one file per drawing, then using AE to create the desired timing. This establishes a naming link which will be used throughout the project. It reduces the amount of storage space because you won’t have multiple copies of drawings, and it allows you to experiment with timing the sequences in the SW, where multiple variations are relatively easy.

THE ESTHETICS OF DOWN-SHOOTING
When you use a scanner to digitize drawings the process actually occurs under the hood, hidden away from your scrutiny, like baking a cake in an oven. So, there may be little problems like dirt and mistakes that you wouldn’t notice until later. Using a DV camera does limit your resolution but it allows you to witness each drawing as it enters the production stream. You may want to alter your concept and shoot the drawings in macro focus to accentuate the paper grain and stroke irregularities, alter lighting effects or just catch mistakes. And you may want to combine sequence techniques with more direct methods like collage and material manipulation.

STOP MOTION CAPTURE IN PREMIERE
(applies to Premiere 6, the last version released for Mac)
Make sure your Project settings are compatible with your capture settings. Go to File>Capture>Stop Motion to bring up the SMC window. Consider making this a Command which can be evoked with a function key. The Stop Motion Menu lets you set Recording Settings (make sure it matches the video source size) and Video Input. If you see no image in the SMC window go Video Input>Source to make sure you have chosen the right source. Remember, a DV signal looks a little chunky on the desktop but will look sharp on an analog monitor. When you capture in Premiere the files are stored on the Scratch Disk which you set in Preferences. Make sure you save to a specific folder.

SMC will let you play back as a clip immediately after capture, thus making it good for testing. If the sequence is animating at a consistent rate you could capture only one frame for each drawing and slow down the speed of the clip to achieve the proper speed. If your sequencing is irregular and you want to see a test immediately you could simply shoot the scene one to one, as shooting on a linear medium, but remember this is just for testing and you will have to recapture for final.

Once the files for a particular layer have been captured and played as a test from the clip window import into a capture project which you save, then place on the timeline, preview, and render as a PICT sequence. Premiere adds its own numbering convention. You can also export as a Quicktime or as a Filmstrip (one super long segmented file that can be painted in PS, then animated in AE)

Final Cut Pro does not capture single frames.

STOP MOTION CAPTURE WITH FRAME THIEF
Frame Thief, a well-designed $40 shareware(www.framethief.com), captures individual frames to a folder and lets you customize naming and numbering conventions. It assumes that the files will then be imported into AE to be interpreted for sequencing. A low rez playback is possible in the preview window. When you pay for the shareware you can unlock many extras such as onion-skinning to see the last frame shot, a real plus for tabletop and direct shooting. The Preferences window allows for wide range of shooting and input options. Version 2.1 is a major upgrade with a useful PDF manual and a plug-in for DSC (but it still needs work).

Another option is iStopMotion. Windows users can go to stopmotionpro.com.

EQUIPMENT
You need: a Hi-8 or DV camcorder mounted on a copystand with flat incandescent lighting on both sides and a peg bar; a lightbox would also be nice. Each camera has a different pixel shape and resolution (640 X 480 square pixels, 720 X 480 rectangular pixels), and a different interface with the computer (s-video, firewire). For testing even the lowly composite video camcorder will work. But for the best quality the extra $ spent on a 3 chip DV camera are worth it. I use a Sony TRV900.

The camcorder can also be used to record the final animation. DV can be dubbed to the more robust medium Digital Betacam, without a loss in quality. But I generally layoff the finished film directly to Digi-Beta or film by using a service bureau, the equivalent of a digital lab.

The Canon G3 DSC can capture directly to the computer HD (i.e. NOT to the memory chip and then downloaded) using the included software, Remote Capture. It’s quite fast even though it uses a USB interface. The settings for white balance, exposure, and focus can be set manually and locked, and resolution can be 640 X 480 up to 2K thus making making it an attractive digitizer for video or film resolution. The current price is about $500, about 1/4 that of a 3 chip DV camcorder, but with a much larger CCD, and similar quality optics. There are other DSCs from Nikon, Canon, Kodak, starting at $2000, which have reflex viewing, Firewire interface and interchangeable lenses. But for me the G3 works fine.


FOLDERS
Following traditional conventions each sequence must be kept within its own layer folder and each layer folder must be kept within its scene folder. Keep these folders in a folder called Scans. As you render them for animation you can make another folder called Final Art. Or, better yet, keep the original scan as an invisible PS layer. You should always back-up your source files and once these files have been imported into AE do not try to move them around to other drives or directories; you run the risk of breaking the link to the AE Project. Organization is essential.

PHOTOSHOP RENDERING/LINES
This sense of render means to make useful for animating, specifically by clearing the paper opacity, isolating and styling the line and adding color. You can save time importing by dragging all files from their layer folder onto the PS icon. The files will be opened as PS files and stack up neatly, ready to be cleared. The conventional order of tasks would then be:
1. Copy background layer; this becomes your work layer
2. Hide background and rename it orig scan
3. Select line with wand
4. Select similar
5. Reverse your selection to select the paper background
6. Clear selection
7. Clean up as needed
8. Save by overwriting original file
You can script 1-8 by recording it as an action thus automating the process. Consider variations, such as uniformly enlarging or reducing the selection, filling the selection with black or a color, softening the selection with a slight blur, adding filters to the selection, playing with tolerance options of the wand tool (to get higher discrimination between line and paper). You may want to adjust contrast and brightness before clearing. Beginning with inked, contrasty drawings will be a major asset.

Another clearing strategy can result in a much cleaner separation:
1. Dupe BG layer then hide it
2. Adjust Curves for optimum contrast
3. In the Channel column Select only one of the channels (R, G, or B)
4. Dupe and name it Alpha.1
5. Make a new layer in the Layer Column; name it New Line
6. Load Selection Alpha.1
7. Fill selection with desired color or black.

These steps allow you to preserve the transparency of edge pixels, thus avoiding remnants of white background. And you can script the action using Actions.

With either approach you want to tune the file for highest contrast without losing detail BEFORE clearing the background tone. And if saving as a PS file (to be imported as a sequence later into AE) you preserve all layers, and they can be edited at a later date.

PHOTOSHOP RENDERING/COLOR
Coloring can be done directly on the line layer by painting behind (see options for brush, bucket, or fill), but it is more prudent to use a separate layer for each color. These would normally be stacked below the line layer.
You select the area to be filled in the line layer then switch to the color layer to fill; you can enlarge the selection to ensure the color edges are covered by the line. Don’t discard the original scanned layer; you may need it later.

If you have broken lines you may need to do some hand brushing to fill the leaks. Playing with option adjustments for selecting may automate this task. You will find drawing with a Wacom pen in one hand and performing keyboard shortcuts with the other hand will be the fastest way to work.

The main beauty of using Photoshop is that it can be customized to a higher degree than any of the current digital ink and paint programs which also tend to be expensive and have limited I/O capabilities. Photoshop can import files from virtually any other SW, such as Illustrator or Painter with its diverse brushes (PS 7 has beefed up its own brush arsenal), color can be applied in a dazzling variety of ways (e.g. why stay within the boundary lines?), with textures, shading, opacity controls. Consider testing the wide array of effects that come with PS, but be careful and test the effects when they animate in AE. Many of the effects in PS are available in AE where they have dynamic variables, so don’t lock down the design before experimenting later (e.g. Noise will be a random boil in AE, but static in PS).

As a creative option consider importing line and color as separate sequences into AE then applying different effects to each layer.

DIGITAL COLOR
Because color standards vary between platforms and monitors you should pay attention to Color Setup in PS. Set this preference along with other prefs and make sure all computers you may work on are set to the same color profile (I prefer Apple RGB rather than the default sRGB). When choosing colors for your animation you should test them on a composite NTSC video monitor, their ultimate showcase. This should be a professional monitor which can be adjusted for hue, contrast, and brightness. A TV will do in a pinch. In general, colors which look good in RGB color space will look too saturated in NTSC, a YUV color space. Reds are particular offenders. Also keep your blacks and whites within a 15-235 RGB value. These esthetic issues relate to technical broadcast standards and may lead to a tape being judged unacceptable for television transmission.
Preview on a TV monitor may also reveal nettlesome buzzy artifacts, often caused by too much color saturation, which can be fixed in the original file in PS before importing to AE, or even after it has been imported by Replacing the File (Com+H). Horizontal lines 1 pixel or less than will tend to vibrate. To fix, increase the thickness or soften with a gaussian blur.

SETTING UP AFTER EFFECTS
First, you should get in the habit of saving your work every five minutes (Com+S) because AE doesn’t do it automatically. Com+Z will undo and if you need to go back further you can Revert to the last saved version of your project.

AE has a deep range of tools and controls for video compositing and sequencing but most of the work is performed in 4 specific windows: the Project Window, the Timeline, the Comp Window, and the Layer Window. You will need to keep the first 3 windows visible all the time.
When you first start up AE, an untitled Project Window appears; you make a new Comp (Com+N). The Comp settings window automatically appears; chose the size and frame rate and name it, then save the Project to your data volume. You can reset Comp specs later by going Com+K.

Give your Comp a name. Use Scene numbers or sizes, or Main if you want to hold several scene comps. Notice the drop-down menu of size presets or type in your own custom size. Frame rate should conform to your final medium. Set duration and start with frame number 1. Resolution can be set later in the Comp Window where you may be changing the size and rez quite often.

Remember that these settings can be changed but if the comp is nested with another comp changing the frame rate will affect the length of comp and synchronization points. The Advanced tab lets you set the shutter angle which affects the amount of possible motion blur.

At File>Project Settings specify the time display as Frames and set first frame as 1. Color Depth defaults to 8 bit; 16 bit is for 35mm film work.

Next go Edit>Preferences.
General: Synchronize Time of layers and accept the defaults, though you may want to limit the undos to speed up work.
Previews: establish proper audio length and specs.
Display: Lets you limit data display which may speed up operations.
Import: Set sequence rate for output medium (30 fps for video is the default). I change to 29.97, same as the Frame Rate for Comps designed for video.
Label Defaults: I like Composition to be red.
Cache: affects speed of RAM preview compiling.
Video Preview allows you to play out desktop to via a video capture card or firewire.
All other prefs work well for me at default settings but you may want to customize the interface even further.

PIXEL SHAPE?
A Comp can be any size, measured in pixels, but pixels come in two shapes: square or rectangular. All graphics programs operate in and display square pixels but all standard video (DV, D1,and Beta) is based on a rectangular pixel shape. The standard video size of 720 X 486 (non-square) is equivalent to 720 X 540 (square); both are 4:3 aspect ratio. A perfect circle will look like an oval on the RGB monitor, but the video card or coding box will compensate and draw a perfect circle on the NTSC monitor.

When you are creating files in Photoshop to be animated in AE you should use 720 X 540. When you drag those files to your video rez AE Comp they will be taller than the Comp. While the file is selected go Com-Opt+F to squash it to fit. Another strategy is to work in a square pixel Comp until ready to see it on video, then drag that Comp into non square pixel Comp.

Remember, the pixel shape issue only affects video, not film or web animation.


PROJECT WINDOW
Just as you organize your original file storage directory with hierarchical folders you should maintain a clean, logical Project Window; it acts as an index of all imported data and all nested Comps. It is your portal. Create scene folders containing sub-folders for each layer element, a folder for Comps, another for audio files, another for movie clips, another for stills, or reused elements, etc. Rename all icons here by selecting, hitting return, and typing. If you open this window wide enough you can discover a file path back to the original data. Remember certain tasks (like Interpretation) are performed in this window which will affect files in all comps. This is where you replace footage and perform other actions which affect files globally.

IMPORTING SEQUENCES
AE does not capture images directly, so it’s very important to follow the rules when importing files as a sequence.
1. One folder for each sequence. As covered in SCANNING, pick a letter or a word to identify the sequence and a sequential numerical run with lead-zeroes so that the order is maintained in the folder. Keep it simple.
2. Each sequence will occupy one layer. Do not try to combine more than one element in a sequence.

The sequence is imported by one of two methods. From within AE go File>Import>File (Com+I), navigate to and open the folder, select the first file, click the import as footage box, make sure the sequence box is chosen, and click Open. The files will appear as a stacked file icon in the Project Window. The other method, from the desktop, is to simply drag the folder icon onto the Project Window.

INTERPRET FOOTAGE
When you import a sequence of files, AE treats it as a movie running at a 30 fps (set this in Preferences>Import). You must change this by using one of two methods. The simplest is called Interpretation. To make a sequence animate at a uniform speed (e.g. 2s) select it in the Project Window and go File>Interpret Footage>Main (Com+F). If a sequence has been imported at 30 fps an interpretation of 6 fps for the layer will yield a sequence on 5s. Interpretation will also let you loop the sequence and spec the alpha channel, which is important for PS files which use the Alpha channel to create a clear Cel. If the footage really were a captured movie it would already have a frame rate which you could alter by using this window.

FILE TYPES
Because Adobe publishes Photoshop, Illustrator, and Premiere there is an interface similarity with AE . With enough RAM you can keep AE and PS open simultaneously and go from one to the other in a seamless workflow. Do yourself a big favor and memorize certain keyboard shortcuts (depending on your platform) for Edit Externally (Com+E), and Replace Footage(Com+H). Dont forget to save your change in the other app. The update may occur automatically without having to replace footage. PS and AI Comps import with all layers, even the invisibles. Its important to name your layers clearly so if you need to go back and change and reimport a layer you'll know which one.

Adobe Illustrator files are vector-based, hence scalable prior to rasterizing (which fixes them as bitmaps), and commonly used as a source of type files for animation in AE, or for any precisionist design. Special consideration must be paid to registration of sequence files (use crop marks), and the particular version of Illustrator may have to be tested, but otherwise they work the same as bit map files in AE, either individually or as a seq. You can copy and paste a path from AI to a layer in AE thereby creating a new mask which can be animated, adding yet another realm of plasticity.

AE can also import Photoshop files, PICTs, TIFFs, JPGs, Targas (and a host of others formats) as a sequence. The MacOS doesn't require the file extension for identification so you can set PS saving prefs to leave it off. If you expect to be using Windows in your production (maybe at a service bureau or lab), leave the extension in the file name.

PS COMP
PhotoShop files imported as a composition (not as footage) is the most important format for those planning to do collage animation. All alpha channels are imported intact so masking effects (but not quick masks) are preserved. This permits the animator to work up a design in PS into a multitude of options in as many layers before applying timing and other geometrics in AE. Character animation using a PS Comp would not be as exacting as sequence drawing, yet could yield results similar to cutout animation, particularly when animating the anchor point as well as the position. You could even draw a sequence in a PS comp using the layer opacity sliders as a lightbox, then save the layers into another folder for importing to AE as a sequence. Be sure to identify your layers.

When import a PS Comp, AE automatically makes an AE Comp with all the PS layers, and a folder containing the layers; both saved in the Project Window. If you find that a layer needs to be edited, select it in the Project Window and go Com+E which will open the PS file; make the changes and save; the file will update when you return to AE.

TIMELINE WINDOW
This window is as close as AE comes to an exposure sheet. It certainly could be a lot better for cartoon animators, but it does offer many options unavailable to conventional animation. When a file is dragged to the Timeline it can be positioned at any level, and it will automatically plop down at the current time marker unless you force it to a particular position on the timeline. An identity tab at the top of the window lets you shuffle and arrange all your Comps. Into the layer lines of each Scene Comp you will drag in the necessary files to build your scene--backgrounds, foregrounds, sequences, sound files.

TIMELINE AS EXPOSURE SHEET
Like a traditional exposure sheet the Timeline is organized on 2 indices: Time (running left to right, like a score) and Space, or more accurately Depth (running top to bottom, representing the stacking order of the Layers). Its time scale can be adjusted by going + or - on the letter keys or using the slider at the bottom of the window.

A crucial concept for understanding how AE works is that it runs and calculates in real time: frames of film and video which occupy real physical space are, in AE, merely concepts reflecting decimal fractions of “real” seconds during which an image is displayed. The “frame’ space in the Timeline is represented by a scalable horizontal line, not a fixed-sized box as in Flash, and when you play back animation in a preview the Time Controller will indicate the exact playback rate, compared to the Frame Rate you have chosen for the Comp.

Layer stacking order determines foreground and background element placement which of course is the key to building your composition. You need to select a layer to work with it (shift select for multiple selections), or use the numeric pad numbers. Memorize the Keyboard Shortcuts for Layer Properties to minimize your work space. I find these very useful:

S: Scale
P: Position
R: Rotation
T: Transparency
A: Anchor Point
RR: Time Remap
LL: Audio Waveform

TIME REMAP
Unlike Interpretation of sequences which you do in the Project Window and affect the sequence globally, Time Remap is done in the Timeline, affecting only the that particular Comp. If the sequence has an inconsistent speed, with random holds and reusage, as with much character animation, particularly mouth actions, don’t use Interpretation for sequencing; use Time Remap. These two methods can be both used together but it will lead to many headaches, so if you have interpreted a sequence just to test it, and now you want to TR it, go back and make sure the interpretation conforms to the Comp’s Frame Rate. They are really mutually exclusive.

When you drag a sequence to the Timeline Window it will be raw data, just like your stack of drawings, and TR will let you sequence them just like an animation camera. In the Timeline Window select the layer, go Layer>Enable Time Remap (Com Opt+T). You will note that the layer automatically expands to fill the comp and when you twirl the triangle open there will be 2 default linear keyframes at the beginning and end of the sequence. First, select all keyframes (by simply selecting time remap, then Toggle Hold (Com Opt+H) them, then delete the second keyframe; you will be adding your own KFs. Now, set about adding all the necessary KFs to translate the sequencing from you exposure sheet to the Timeline. I do this by using the keyboard exclusively:

1. Advance frame by frame on the Timeline (Com+Right Arrow or Page Down).
2. Park your cursor on the window for the file number and select it.
3. Type in the proper file number.
4. Hit return.
5. Advance again.
6. Tap your mouse to select the file number box.
7. Type in next file number.
8. Etc.

Use cut and paste to add repetitive sequencing, like cycles. Once you have a mini-sequence plotted you can select KFs by drawing a marquee then going Com+C, advance to the frame you want and Com+V (basic Apple commands). It isn't as elegant as a true exposure sheet but it does work. You will find it easy to expand or contract the timeline resolution by hitting the plus or minus keys (those above the letter keys). And navigating to the next (K) or the previous (J) KF will make your task easier.

Treating every keyframe as a Hold is analogous to holding down the expose button on an animation stand. If you carefully track frames to files you can toggle back to Linear interpolation for long runs in ascending or descending order. Notice that Interpolation is similar to Interpretation in that it is a kind of setting, but don’t confuse the two. Interpolation affects space and timing, hence acceleration, of all keyframes, including those which govern the geometrical properties (e.g. position, rotation, scale ) of specific layers in the Time Layout Window. The KBS for accessing interpolation for selected keyframes is Com Opt+K. For TR you need only consider Hold (shaped like a box) and Linear (shaped like a diamond) because the Interpolations like Bezier will vary the speed by adding or subtracting frames which may produce unintended results.

To access a layer’s TR properties alone, select the layer then hit RR.

PENCIL TESTING
If you have just captured and imported your sequences and want to time them and see the animation even before clearing and coloring the files you can do a temporary clearance of the paper color by using Layer Modes. F4 will toggle from Switches to Modes (where you choose Darken which will make the white paper background transparent). Experimenting with Modes effects on finished layers will reveal unexpected and quite stunning visual textures, particularly when applied to a duplicated directly above the original layer.

RAM PREVIEW
Animation is tedious and time-consuming. After drawing all day it is so gratifying to grasp the drawings by the scruff of their wrinkled necks and flip them for a little kinetic thrill. When shooting onto film (an even more tedious process involving lights, cels, finicky gears, sprockets, bad coffee, short tempers, and lower back stress) one had to wait 24 hours for a lab to process and print the results which were then displayed on a clattering moviola. In AE you simply push the numeric 0 to load the work area into RAM, then watch it play back on your desktop. The work area can be easily defined by placing the current time, blue triangle at your beginning (B) and then at your end (N). It’s a good idea to load only what you need into RAM, and select loop. Hitting the SpaceBar will stop the loading and play whatever is in RAM.

To save time you can limit the comp size (always keep scale and rez the same: e.g. 1/2 size at 50%). When it plays back in the Comp Window the actual speed is noted in the Time Control window. To extend the length of preview with limited RAM you can Shift-0 to load every other frame which then plays back at a kind of cut rate real time. Ram preview can be used to check mouth actions with a sync audio track; Com+Opt scrub timeline for close analysis. Obviously it pays to have as much RAM devoted to AE as possible (if you are running OS9). If you aren’t able to preview as much as you think you should, try purging all your RAM at Edit>Purge>All. AE knows what parts of the comp have been changed so subsequent previews render only the new material.

In the Time Control Window you can twirl down the arrow in the upper right corner to show more options for Ram Preview. The main purpose of RP is to playback at full rez on your desktop to see how comp will look in the final. In Preferences you can have AE also play out via firewire or a video capture card. This would provide an even more faithful preview because the superior desktop image may have some redraw artifacting even as it runs at full speed.

COMPOSITIONS
The primary organizing stage is the Comp. I generally create a Comp for each Scene, a Main Comp containing all the Scene Comps, and several Render Comps which contain the Main Comp. Even the Scene Comp may contain secondary Comps. This method of nesting Comps helps organization and workflow by separating completed tasks from current tasks; a schematic diagram of this workflow can be pulled down from the Windows menu. To synchronize all Scene Comps in the Main Comp make sure they are the same length as the parent Comp and placed at the beginning of the Main Comp (hit the Home key). Adjust the Comp’s visibility markers for time needed. You want to be able to navigate easily from Main Comp to Scene Comp, and remain at the same point in time.

PRE-COMPING
When you build a composite object (character or mechanism) from several layers to which you have applied dynamics you benefit from pre-composing (Com-Shift+C) the selected layers to make a new Comp. This comp can be animated more easily as a single layer. For example, a character walking on a cycle and talking with TR’d mouth actions can be Pre-Comped and then panned across the background or scaled, or a car with rotating wheels can be Pre-Comped then panned.

A simpler method for linking layers is to use the parent/child switches in the Timeline to subordinate one or more layers to a guide layer to mimic its dynamics.

LAYER WINDOW
You can create a native layer from scratch in the Time Layout (Com+Y).
It might be for type, a visible solid layer, or a masking effect. In the Timeline Window any layer may be double clicked to bring up its Layer Window where you can use vector tools to create simple or complex, multiple masks which can be feathered for a blurred edge. The vectors are paths defined by points, each of which has an animatable handle. Get to know the tools (V=selection, G=pen, H=hand, W=wotate, Q=marquee) and their modifying keys (Shift and Com). Masks can be used to “draw” shapes which can be animated by keyframing the Mask Shape.

Consider animating a complex mask shape by clicking the Keyframe stopwatch symbol at frame one on the mask shape line, advancing 10 frames (Shift+page down), changing the shape by displacing the points, advancing 10 frames more, make other changes, etc, etc, and then copy/paste the first keyframe at the end for a cycle. The shapes can glide fluidly from one KF to the next, or use more Hold KFs to cut to a jerky rhythm for a more angular animation.

When you are in the Layer Window notice the little black arrow in the upper right corner: it can let you select the Anchor Point or work with masks. All imported files have a default Anchor Point at their center. By realigning the AP you may have more control of your KF animation, e.g. shift the AP of a character’s head to its neck area to do a more naturalistic rotation dynamic. Notice that changing the AP in the Layer Window will have an effect on the layer’s position in the Comp Window, requiring adjustment.

COMP WINDOW
This is, of course, where all your animation and design work is made viable and visible. To speed up your work keep all layers in Draft rez (jagged left-leaning bar) and, if necessary, keep the Comp Window small (hit period or comma to zoom). Changing the Comp Window rez must be done by mousing; I tend to keep it full size, full rez.

Remember, if you have applied just one KF to one of a layer’s Transform attributes and you alter it by dragging in the Comp Window a KF will automatically appear for the appropriate attribute line, and it will be interpolated just like the other KF. Conversely, if you have not set a KF, then if you drag a layer you are setting its attribute for the duration of the layer, not just that point in time. For this reason it is very helpful to open your Timeline up as wide as your screen will allow so you can read each line in its entirety. The visibility factor also affects navigating by stroking J and K.

LAYERING STRATEGIES
In the Comp Window you see the results of layer stacking order, which can be altered by dragging in the name column. In the ancient days of cel, painters had to follow match lines to imitate the appearance of layering. In AE you can simply duplicate a layer and sandwich a third element, then draw a subtractive mask (e.g. a bird in a nest, partially obscured by the foreground side of the nest). Remember all masks can be dynamic by adding KFs on the Mask Shape line.

Another technique for altering the layer structure is to split a layer to change its stacking order. As far as I can tell this just Duplicates the layer and automatically resets the visibility handles. This duping process is valuable for negotiating character movement through complexly-layered environments.

A traveling matte used to be a silhouette black and white film element sandwiched with a color element so as to black out or reveal a particular area. In AE you can create a layer over the layer to be matted, toggle open the Modes (F4) and call it a Track Matte. Chose from Alpha or Luma, normal or inverted, and the layer (with whatever masking you have created) will affect only the layer directly below it.

Many other layering strategies, imitating multiplane animation stands, or using variable pan speeds to mimic deep space dynamics, or altering focus by adding blur effects will readily come to mind when planning your cartoon.

KEYFRAME : CUTOUT : COLLAGE
We have already learned about Keyframes for sequencing, but more commonly Keyframes are used for controlling the dynamic properties of the Layers. A PS Comp with multiple layers can be animated by displacing layers through time and adding keyframes to control moth the path and speed of movement. This technique is quite similar to “cutout animation” in that the layers are animated through displacement rather than replacement. When a layer is a sequence of files animating via replacement you may combine it with other layers displaced or scaled with KFs.

A common example is a character moving on 2's or 3's interacting with background sliding on 1's, a default situation if you use 2 keyframes to define the beginning and end of a layer dynamic. The interaction may look a bit off. To overcome this slippery problem try inserting a hold keyframe every time the character sequence changes, i.e. animate all affected layers to the same rhythm. With the remapped hold KFs visible simply navigate through the sequence (K forward to next KF, J backward) and add a KF (by selecting the KF box) on the Position line. The path will remain the same but it will be filled with a bunch of diamonds. Finally, just re-interpolate the KFs by selecting all of them and hitting toggle-hold (Com-Opt+H).

This lesson is for a fairly conventional problem of figure/ground animation but the deeper implication is that cutting from one position to the next (this is what the Hold box does) will generally give you more control over the flow of movement. This is the old time religion, not really in tune with the computational sensibility realistic motion, but I believe it will serve the character animator as well as the experimentalist. If the word "animate" still means “bring to life” it does not mean merely guiding an object along a path, especially a perfectly executed "elegant" arc, at perfectly allotted intervals. Film animators worked out a choreography of necessity which gave their characters a distinctive snap and presence. This sense of timing is often lost in programs which usurp control from the user.

But, of course you do need smooth motion sometimes. And when you do, AE will provide it with ease. Layer Properties, can be orchestrated in time using bezier handles to graph the dynamics of Position, Rotation, Opacity, and Scale. Many manuals cover these techniques.

KF ACCELERATION
By selecting the start and stop KFs in your dynamic, then dropping down the detail layer you can spec the speed variables of the motion, what animators call easing, feathering, or tapering. If you're lazy just stick to Easy KFs (Animation>Keyframe Assistants). Remember AE reverses the cel animator's In and Out, e.g. instead of thinking about an action as easing Out at the end of the action, AE thinks of the path as easing Out away from the keyframe, or In to the keyframe. Just get used to it. But if you want to have fun with acceleration in extremis and woozy choreography use the bezier handles to pull your own timing arcs to shape velocity into instant, testable results. You will notice how motion conforms to naturalistic physical laws and how you can exaggerate or undercut them, both in motion paths, editable in the Comp Window, and in the layer properties in the Timeline, where you can expand the height of the work area for a better view.


MOTION BLUR
In the Project Settings you can set the Shutter Angle (default is 180 degrees, just like a movie camera) up to 720 degrees (a delicious impossibility in the real world). This setting bears on the motion blur effect which you enable by checking the M box in Timeline Switches. To see the effect in the Comp Window you need to select the M box at the top of the window. Motion blur will affect only those layers which you have animated using KFs. There is also a clever plug-in called Reelsmart Motion Blur available from revisionfx.com that lets you apply blur to any sequence or movie.

Using a motion blur to break up and soften hard-edged graphics in motion is an obvious complement to the numerous tools AE provides for randomly animating layers and forms within layers. In the old cel days animators used to confine themselves to such mundane issues as how to prevent pan strobing. The only way we could get a blur was to move an object under the camera while shooting. Now, we can experiment with a wide range of “motion un-control.” Consider:
THE WIGGLER
VECTOR PAINT WIGGLE
PATH TEXT JITTER
MOTION MATH



SOME REMINDERS:
SAVE: every minute
BACK-UP: every day
REVERT: when you’ve gone too far to salvage a task.
DUPLICATE PROJECTS: “Save As” to try alternate versions.
DUPLICATE LAYERS: to manage stacking order problems.



MORE TO COME IN LATER DRAFTS:
Traveling Mattes and Alpha Masks
Handling Nested Comps
Rendering strategies
Animating paths and masks
Path Text animation
Layer Modes
Vector Paint
Harnessing randomness: jitter, wiggle, flicker
Consolidation and backup strategies

George Griffin 8/04

Note:
I have tried to revise these notes to include working with OSX and AE 6, but there may be mistakes or oversights above. There were bugs in Time Remap and Vector Paint in early versions of OSX and AE 5.5; they seem to be fixed in the 6.0. Check web user-forums to find out if upgrades are OK to install on your system:

http://www.creativecow.net/
http://www.adobe.com/support/forums/main.html
http://www.media-motion.tv/thelists.html#Anchor_new1
http://msp.sfsu.edu/Instructors/rey/aepage/aeportal.html