Autodesk Smoke Essentials: Autodesk Official Press (2014)

Chapter 7. Using Axis Effects

In the last chapter, you experienced your first introduction to timeline effects through the use of the dissolve and timewarp effects. In this chapter, you’ll learn how to use the power of the Axis tool in your Autodesk^® Smoke^® installation to build some rough composites in order to determine how two sets of superimposed clips should cut together.

Topics in this chapter include the following:

· Editing superimposed clips

· Creating a picture-in-picture effect using Axis

· Tracking a superimposed clip to match a background

· Editing and keying a superimposed greenscreen clip

Creating a Picture-in-PictureEffect Using Axis

This scene has several multilayer composites. While the final shots will be extravaganzas of layered effects, as you initially edit the scene, you’ll often want to start by creating a simple placeholder composite so that you can figure out the timing of the different layers and see how well they’ll fit together before you start the really time-consuming part.

However, an advantage of Smoke is that your placeholder effects can actually be much nicer-looking representations of the eventual composites than a piece of text that reads “VFX HERE.” In particular, by learning how to use the timeline effects, including the versatile Axis effect, you’ll be able to create effects that will be convincing enough to give your first test viewers a clear idea of what is to come.

Editing Superimposed Clips with the Source-Destination Controls

Option-clicking Audio+ adds a stereo audio track, while Command-clicking the Track+ button adds a new track below the positioner’s focus point. You can also right-click the Version+, Track+, and Audio+ buttons to find additional commands in the context menu.

Before you get started, you need to lay the superimposed clips with which you’ll be working into multiple video and audio tracks.

1. Duplicate the Opening Scene sequence, and rename it Opening Scene C07.

2. Open this new sequence, click the Track+ button underneath the patch panel area to add a new video track, and then click the Audio+ button twice to add two new mono audio tracks (see Figure 7.1).

FIGURE 7.1 The Add Track buttons under the timeline patch panel

3. Whenever you add a new track, the focus of the positioner automatically moves to that track. In this case, you don’t want the focus to be on audio track A4, so press Page Up four times to move it to track V1.1. (Page Down moves the focus of the positioner down.)

4. Press Option+2 to set the viewer to Source/Sequence mode, and then find and click the clip noted as 13_A_03 in the Media Library to open it into the source viewer.

5. Play through the man’s clip, and set an in point where his two fingers are first extended (01:03:10+05). Then set an out point at the frame where he finishes swiping with two fingers the second time (01:03:23+12).

In the movie, the character’s finger swiping corresponds to a heads-up display that needs to be composited to be seen.

6. Play through the fifth clip in the timeline to the frame where the woman’s two-finger swipe is almost finished (19:54:32+11 relative to the source timecode). This is where you want the man’s videoconference clip to appear.

Up to now, you’ve only edited clips into video track V1.1 and audio tracks A1 and A2. This is a common way to work, given the plethora of trimming options available to you. However, once you start getting into compositing and the assembly of complex layered montages, you’ll need to start editing clips into multiple timeline tracks. The green source-destination controls in the patch panel area let you control into which tracks clips are edited.

The sequence viewer shows the source timecode of any clip on the same track as the focus of the positioner. If the focus is on a video track with no clip at that location, no source timecode will be visible.

7. Press Page Up to move the focus of the positioner to video track V1.2, and notice how both the green V1.1 source control and the red P (for Primary) button move up (see Figure 7.2). Moving the positioner up and down also reassigns the source-destination controls that determine into which video track an incoming edited clip is placed.

FIGURE 7.2 Reassigning the positioner and video source control to track V1.2 (timeline shown zoomed in)

Before you make this edit, however, take a quick look at the timeline and notice that the green A1 source control is connected to the destination control of track A1. Every time you open a clip into the source viewer, the tracks within that clip create an equal number of green source controls, and you need to reassign source A1 to another destination audio track if you don’t want to overwrite whatever is currently in timeline track A1.

8. Click within the source control of track A3, and drag to the right until it shows the green A1 source (see Figure 7.3). If the source clip had more than one audio track, then dragging to the right would cycle among all of the available sources. (Most of the clips provided for this book have six audio tracks.)

FIGURE 7.3 Reassigning audio source control A1 to timeline track A3

9. Now, with source V1.1 assigned to V1.2 and A1 assigned to A3, press F10 to overwrite edit the marked portion of the clip in the source viewer so that the in point aligns with the playhead’s focus (see Figure 7.4).

FIGURE 7.4 Editing a superimposed clip into the sequence

Now that this clip is in place, it’s time to turn it into a floating video window.

Using the Axis Effect

As you’ll see, the Axis effect is a multipurpose timeline effects tool that has options for 3D transforms, keying, rotoscoping using the Gmask tool, tracking, and stabilizing. In the following exercises, you’ll use the Axis effect to resize and reposition the clip of the man to appear as a video window.

1. Move the positioner so that it intersects the clip you edited into track V1.2, and then click the FX Axis button in the FX Ribbon.

The FX Ribbon immediately updates with a subset of the Axis parameters that are useful for adding a matte; altering the position, scale, or rotation of the clip; and compositing it against other clips using transparency and blend modes. You’ll start with these.

2. Using the FX Ribbon controls, drag the Scale X parameter to the left to shrink the clip to a value of approximately 60. (The Scale Y parameter is automatically locked to the same value.) Then drag the Pos (position) X parameter to move the clip to the left (around −280), and drag the Pos Y parameter to move the clip up (around 100).

As you make this adjustment, you can see the underlying clip in track V1.1 showing through, automatically composited. However, you can make this composite a bit more integrated by playing with transparency.

3. Choose Screen from the Blend Mode pop-up menu, and drag the Trans (transparency) parameter to the right so that it’s about 20 percent.

At this point, the image should appear something like Figure 7.5. Play through the clip and see how it looks.

FIGURE 7.5 The repositioned and rescaled superimposition

The transform and compositing bring the clip of the man into the scene by making room for the woman’s over-the-shoulder position, but while the result is acceptable for a very rough cut, you can do better using the Axis editor.

4. Click the Editor button on the FX Ribbon to enter the Axis editor, and then choose Fit from the Zoom pop-up menu to fit the entire available area of the frame into the viewer. Unfortunately, the Axis editor’s viewer is showing the low-contrast look of the log media.

5. Click View (see Figure 7.6) to display the View controls, and then choose Logarithmic from the Image Data Type menu to set the viewer to display the clip in Log mode. When that’s done, click View again to return to the main Axis editor controls.

FIGURE 7.6 The viewer controls in the Axis editor contain the Zoom control, the Tool pop-up, and access to the Grid, View, and Pan/Tilt controls.

There are several sets of parameters in the Axis viewer that you view by clicking a button and dismiss by clicking the same button again to turn them off. These include Grid, View, Setup, and Animation.

Now that you can see what you’re doing, it’s time to make a few more adjustments to marry this clip more convincingly into the scene. In particular, the Axis editor gives you full access to the full 3D compositing environment that’s available in Smoke.

6. Drag the Y rotation control to the right to tilt the image in about 12 degrees. Once the Y rotation control has been altered, you can see an onscreen rotation control in the viewer that exposes all three axes of rotation (see Figure 7.7). Try adjusting the clip’s rotation with this control so that X rotation is about 5 degrees and Y rotation is about 15 degrees.

FIGURE 7.7 The transformed picture-in-picture effect

7. With the screen tilted in, it now seems a bit close to the left edge, so drag the X position parameter to the right so that the X position is about −191. Notice that adjusting the position exposes the onscreen position control, which you can also use to reposition this layer.

Just pressing the up- or down-arrow key moves the positioner to the next edit point on the track at the position of the focus. Pressing Control+up- or down-arrow key jumps the positioner among all edit points on all tracks.

8. Play through what you’ve done so far to see how much more integrated this clip is to the rest of the scene.

There’s more to be done, but when you get to the end of the clip you’re compositing over at present, the next clip appears, for which the current Axis effect is completely unsuited. You need to fix this before moving on.

9. Click EXIT to go back to the timeline.

10. Press Control+down-arrow key to move the positioner to the next transition in the timeline, which includes all edit points on all tracks.

11. With the positioner at the in point of the next clip in the sequence and the focus over the superimposed clip, press Control+V to add an edit to the superimposed clip. This automatically adds a cut to both the video and audio when the Link button is enabled (see Figure 7.8).

FIGURE 7.8 Adding an edit to a clip using Control+V

12. Now click the vertical scroll bar and drag to the left to make every track in the timeline taller. Keep dragging until the tracks are tall enough for you to see the dark gray AX proxies attached to the superimposed clips (see Figure 7.9).

FIGURE 7.9 Taller timeline tracks reveal the Axis effect proxy that lets you copy and delete timeline effects.

13. Drag the Axis proxy from the second superimposed clip down to the bottom of the display until you see a little trash can cursor (see Figure 7.10) to delete it.

FIGURE 7.10 Deleting an effects proxy from the timeline

Alternately, you can click the Delete button at the far right of the FX Ribbon to delete the currently selected timeline effect, or you can Option-click a timeline effect’s button in the FX Ribbon to delete that effect.

Stabilization and Motion Tracking

At this point, the clip looks like a video window, but it doesn’t move along with the camera motion of the scene. This is easily fixed using the Axis Stabilizer.

1. Double-click the Axis proxy on the first superimposed clip to reenter the Axis editor in order to continue working.

2. Check that the pop-up menu underneath the Stabilizer button is set to Track, and click the Stabilizer button to open the stabilization controls (see Figure 7.11).

FIGURE 7.11 The Stabilizer button

3. Choose Fit from the Zoom pop-up menu so that you can see the entire frame.

The entire bottom of the interface contains the stabilization controls, which you can use either to track a feature for match moving or to motion-stabilize the current clip to eliminate unwanted motion, depending on the setting of the pop-up menu underneath the Stabilizer button that you checked in step 2.

In this case, you’ll be match-moving the current clip of the man to follow along with the dynamic camera motion of the background clip. When you’re using the Axis stabilization controls, whichever clip is in the next lower track of the timeline is what you’ll be tracking. This makes sense in most compositing situations.

4. Drag the tracking box in the viewer down so that it’s over the left corner of the middle chair against the far wall (see Figure 7.12). This feature is out of focus. When tracking, you typically want to choose a clear, high-contrast feature. In this case, however, beggars can’t be choosers, since camera and subject movement obscure the only other possible tracking features in this clip.

FIGURE 7.12 Positioning the tracking box

In this example, you’re using only a single tracker, but it’s possible to use two trackers to track rotation as well as position by clicking the Tracker 2 button to reveal the second tracker and its controls.

5. After you’ve positioned the tracking box, check that the Direction pop-up menu to the right of the Analyze button reads Forward, and click the Analyze button.

6. Watch as the box tracks the out-of-focus chair back, but as soon as the tracker loses its way and starts wandering across the screen (and it will), click the mouse to stop the track.

Tracking went well for a while, but the focus must have gone just a little too soft and the tracker lost the feature.

7. Click the Reset button at the bottom right, and then click Confirm when prompted.

Sometimes, starting from the beginning of a clip makes it hard to find a feature that will track accurately. Fortunately, you have the option to track in reverse.

8. Click the Direction button so that it reads Reverse; then move the positioner all the way to the end of the scrubber bar and drag the tracking box to the left corner of the right-most chair against the wall, which is now in slightly better focus (see Figure 7.13). Click Analyze.

FIGURE 7.13 Positioning the tracking box for tracking in reverse

9. Watch the track carefully, because one of two things will happen depending on exactly how you positioned the tracker in the viewer. Either (a) the track will lose its way just before the woman’s arm comes up, or (b) the woman’s arm will come up and occlude the tracked feature, knocking the tracker off to one side. In any event, as soon as this happens, click the mouse to stop the track.

In either case, this is not an altogether uncommon problem to have, and there’s an easy method for switching features mid-track that you can use to rescue the situation.

10. Move the positioner back to the last frame where the track was accurate, and then click the Snap button. The outer red tracker crosshairs snap back to the inner white tracker box. Click in the very center of the white tracker box to drag the tracker to the original feature you wanted to track, the left corner of the middle chair back (see Figure 7.14). You may need to zoom into the viewer in order to drag the whole box accurately; if you don’t drag the entire tracking box, this won’t work and you’ll need to do it over again.

FIGURE 7.14 Using the Snap control to change the feature you’re tracking mid-track when a feature becomes obscured

11. Click Analyze, and you should notice that while the red tracker is following the new feature you chose, the motion path being constructed by all of the tracking points in the viewer continues from where it left off, with the result being a smooth, continuous motion track following the motion of the camera.

12. Click the RETURN button, and play through the clip to see what you’ve done.

Now that you’ve returned to the main Axis controls, playing through the clip shows that while the man in the video window is now moving along with the underlying clip, the position has been changed to match the tracker so that it’s now at the bottom of the screen. You’ll need to adjust this, but there’s a dedicated set of transform controls for doing so.

13. Click the Offset button (see Figure 7.15), and use the Position X and Y parameters or the onscreen position control to move the clip back up into the woman’s field of view.

FIGURE 7.15 The almost-final floating window effect

14. Click the EXIT button to return to the timeline, and play through the clip.

The floating window in which the man’s message plays should now follow along with the camera’s motion perfectly, providing a convincing temporary composite that will work until the final composite is created later.

Editing and Keying a Superimposed Greenscreen Clip

In the next exercise, you’ll use the Master Keyer in the Axis editor to do a temporary greenscreen composite in order to determine the range of media in a background plate that you want to accompany this clip in the final composite. After all, you can’t really start compositing until you know which parts of what clips you want to use together.

1. Make sure the Link button is turned on, press R to choose Trim mode, and drag the end of the very last clip to the right until the woman pauses what she’s doing and starts to turn to her right, camera left (see Figure 7.16). Cut the clip midway through her head turn (around 18:30:33+20). Press A to choose Select mode when you’re finished.

FIGURE 7.16 The new out point of the last clip

2. Press Option+2 to put the viewer into Source-Sequence mode, and open the clip noted 01_G_01 into the source viewer. Then play through this clip until you find a frame that matches the action of the woman in the previous clip (17:19:58+00), and mark an in point. Then play forward until you hear the director read the line “Surprised?” and mark an out point just afterward (frame 17:20:04+23).

3. Click the Timeline Layout button at the bottom-right corner of the timeline to reset the height of every track, and notice that there are now four source controls in the patch panel area.

The source audio clip has six audio tracks, of which tracks 1 and 2 are a mixdown, track 3 is a boom microphone, and track 4 is a lavaliere microphone. For simplicity, you’ll be using the mixdown tracks, although you could elect to use one or the other microphone tracks if a particular microphone had better quality. The only reason you’re seeing the additional source controls now is that there are more audio tracks in this sequence, and you’ll have to deal with patching the audio source-destination controls to get the audio you want.

4. Click and drag the source controls (in green) of audio tracks A1 and A2 so that source A1 corresponds to destination track A1 and source A2 corresponds to destination track A2. Then click the destination controls (in gray) of audio tracks A3 and A4 to disconnect them from the source, as shown in Figure 7.17. Now you’re set up to edit only audio into the first two tracks of the timeline.

FIGURE 7.17 Patching the source-destination controls for multiple audio tracks

5. Move the focus point of the positioner to track V1.2, and press F10 (or click the Overwrite button) to edit the source clip you’ve just set up into the timeline on a superimposed track. Having the greenscreen clip on track V1.2 creates a gap on track V1.1 that you’ll use to place the clip that’ll be showing through underneath.

If you look at the FX Ribbon, you may notice that a Resize effect has automatically been added to this clip. This happens when the clip you’re editing into a sequence either (a) has a larger frame size than that of the sequence or (b) has a different bit-depth than the sequence. In this case, the sequence was set to 10-bit processing, but the clip you’ve edited (encoded using Apple ProRes 4444) is a 12-bit clip, so the Resize effect was added to convert the bit-depth.

6. Select the clip noted 01_B_03 in the Media Library to open it in the source viewer, and play forward to just after the point where the woman holding the air gun says “Surprised?” (10:46:33+15).

Press F6 to select the source viewer so that the keyboard shortcuts control the source transport controls. Press F7 to select the record source viewer.

At this point, it’s difficult to set proper in and out points because you don’t know quite how the background clip will play along with the foreground clip. Fortunately, there’s a keyboard modifier that you can use to sync the source and sequence positioners together while scrubbing playback using the mouse. Having both the source clip and sequence scrub together lets you easily see how they line up.

7. Press F7 to switch to the record viewer, and then press the down-arrow key to jump the record positioner to the end of the clip in the sequence.

8. Now press and hold Shift+Control while dragging the source positioner to the left, watching both the source and record viewers, and stopping when you reach the beginning of the greenscreen clip in the timeline. At this point, press I to set an in point in the source clip.

9. Press F7 to switch to the record viewer again, and then press Page Down to move the focus point of the positioner to track V1.1. You may be wondering why you didn’t just move the focus point to this track right away, so play forward through the sequence (see Figure 7.18), and notice that now the record viewer shows only black.

FIGURE 7.18 No video clips above the focus of the positioner are shown during playback.

The focus point does more than just determine into which track incoming clips are edited. It also lets you exclude superimposed video clips from the currently rendered composite.

10. Press the X key to mark timeline in and out points to fit the gap that intersects the positioner on track V1.1, and then press F10 (or click the Overwrite Edit button) to edit the clip of the woman in the mirror onto the timeline using a three-point edit.

Pulling a Greenscreen Key

At this point, the two main clips necessary for creating the effect of the woman’s counterpart from another dimension appearing to her are roughly in place, and you can begin creating a preliminary greenscreen key so that you can actually see both clips sandwiched together in order to better align the action in one with the action in the other.

1. Move the positioner to track V1.2 so that you can see the greenscreen clip in the record viewer, and then click the FX Axis button to add an Axis effect to it. Then click the Editor button or double-click the clip in the timeline to open the Axis editor.

2. If necessary, choose Fit from the Zoom pop-up menu. Then click the View button, choose Logarithmic from the Image Data Type pop-up menu, and click the View button again to go back to the main controls.

With the viewer in the Axis editor set up, it’s time to open the Keyer controls in order to turn the green portion of the image into a transparent hole.

3. Click the Keyer button. The modal Keyer controls now occupy the editor. If necessary, change the Zoom pop-up menu to Fit. (The viewer of each editor in Smoke has independent settings.)

The first thing you see is a confusing blend of both images, because the default key selection is the Luminance key, which by default lets a little of both tracks come through. (This may seem strange, but it’s to allow for proper keying of matte containers when a matte clip is added in Axis.) To the left is a vertical stack of buttons that let you choose what type of keyer you want to use (see Figure 7.19).

FIGURE 7.19 Buttons for choosing which keyer to use, turning on the Master Keyer

4. Click the MasterK button (short for Master Keyer). The editor updates to display the Master Keyer controls.

The Master Keyer is the most powerful and flexible keyer in Smoke. Unlike some channel keyers, which are specifically engineered for keying out blue or green, the Master Keyer is useful for keying any hue to turn it into a region of image transparency. To get started, you’ll use the two color pots shown in Figure 7.20.

FIGURE 7.20 The primary and secondary color pots

5. Click the primary color pot; then position the sample cursor over the greenscreen to the right of the hair at the woman’s shoulder and drag over a small portion of green to sample the greenscreen (see Figure 7.21). The color pots both turn green to show which color you’ve sampled, and the Spill control also turns green to show which color is automatically being suppressed in the image in order to eliminate any possible fringing.

FIGURE 7.21 Sampling the first region of the greenscreen

The green portion of the background immediately turns black (representing transparency), but the initial key is so broad that parts of the woman’s face and the background of the image are being affected, so this result needs to be refined.

Holding the Option key down while moving the pointer over an image being keyed with the Master Keyer dynamically shows whichever matte adjustment sliders are available to manipulate that region of the key.

6. Move the positioner to the beginning of the clip, if necessary, and click the highlight of the woman’s right cheek (camera left)—three sliders appear (see Figure 7.22). If only two sliders appear, then click in the gray area outside the viewer to dismiss them and try sampling a different area of her left cheek.

FIGURE 7.22 Sample adjustment sliders for fine-tuning the matte

These are matte adjustment sliders, and which sliders appear depends on the part of the key you clicked. The Master Keyer is smart enough to display contextually only the sliders that will help you to refine the region of the key that you clicked, so clicking on the woman’s cheek shows you the three sliders that will adjust that area of the matte—Matte Overall, Matte Highlights, and Range D.

The topmost sliders are always the ones that have the greatest effect on the matte, while sliders closer to the bottom have decreasing influence and are typically used to refine small details. The Matte sliders (Overall, Highlights, and Shadow) adjust the entire matte, whereas the Range sliders (A, B, C, D, and E) adjust very specific areas of the matte. The best way to get the hang of these controls is to play with them.

7. Drag the Matte Overall slider to the left until the woman’s face and the wall behind her are opaque, but there is still plenty of transparency among her strands of hair. There will be unwanted transparency in the hair on top of her head, and you’ll start to lose transparency in the greenscreen, but that’s okay. You can’t do everything with one slider. A solid wall is the most important part of this adjustment.

8. Drag the Matte Highlights slider to the left until the hair on the top of the woman’s head is completely opaque. You’ll lose some more transparency in the greenscreen area, but again, that’s okay. These sliders work one step at a time.

9. Drag the Range D slider to the left until the lightest strands of the woman’s hair over the greenscreen become a bit more solid. The end result of the last three adjustments should resemble Figure 7.23.

FIGURE 7.23 First refinements of the greenscreen key

Each of the matte adjustment sliders works similarly: pulling the slider to the left makes that region more opaque, while pulling the slider to the right makes that region more transparent. At this point, it’s probably a good idea to have a look at the matte itself to see how things appear.

10. Choose Matte from the pop-up menu that’s all the way at bottom left. Alternately, you can press F3. You should be able to see that the solid regions of the matte look pretty good, but the transparent area is looking a little ragged, lacking a clean, continuous black area of transparency.

Because this scene was shot in a hurry, the lighting crew wasn’t given enough time to hang and light a truly seamless greenscreen. As a result, the values of green are all over the place, so a single sample is unlikely to do the job. Since this is the reality more often than not, there are Patch controls that let you sample additional areas of the image to improve the matte. A good place to start adding patch samples is any area of the matte where adding a garbage mask would be inconvenient; examples include areas close to her hair or around her moving arm and hand. After all, there’s no point killing yourself to fine-tune an area of a matte that you can easily crop out with a simple shape.

11. Press F4 to view the result again, choose Patch1 from the Sampling pop-up menu at the bottom of the editor, and then click and drag over the gray opaque area within the crook of her elbow. The Patch1 button underneath the color pots should light up, and if the pop-up menu to the right says “Analysis,” click it and choose Black instead to make sure that the Patch1 sample is being used to add transparency (see Figure 7.24).

FIGURE 7.24 Adding to the matte using the Patch controls

12. While Patch1 is selected, you can continue sampling more parts of the greenscreen; drag two or three times just above her arm and within the gray opaque areas just at the upper-camera left corner of the doorway. Eventually, you should be left with only a minimum of solid fringing on the greenscreen immediately surrounding her head and arm, as shown in Figure 7.25.

FIGURE 7.25 The matte after refinement using the Patch1 controls

13. There’s still a gray area corresponding to a portion of the greenscreen on the back wall around her hand, and it appears to have a distinct range of color, so choose Patch2 from the Sampling pop-up menu, and drag around the light gray area (not the tape, which turned yellow in the light and so is now hard to key). It will take several drags to eliminate this light-gray area of the matte.

Each set of patch samples can be individually adjusted and turned on and off, so organizing additional refinements that you’re not sure will work into a separate patch is a good idea, because you can always resample or turn the patch off if it doesn’t work out.

14. At this point, there’s just that tape on the wall. Choose Patch3 from the Sampling pop-up menu, and drag right on top of the tape to sample it. It’ll likely take several drags, but once there are just a few bits of tape left on the wall, drag the Patch3 Range parameter (to the right of the Patch3 button) to the right until you strike a good balance between eliminating the tape and retaining the edge detail of the woman’s hair. If necessary, drag the Soft parameter to the left to eliminate any last bits of the tape intruding into the matte.

Each patch control has range and softness sliders that let you adjust their influence on the overall matte.

15. Now it’s time for one last bit of refinement. Choose Matte from the Sampling pop-up menu, and then hold down the Option key and hover the mouse just above where the woman’s arm crosses the wall until you expose the Matte Overall and Matte Shadows sliders. Drag Matte Shadows to the right to increase transparency within the last, fringed areas of the greenscreen.

While refining a matte using the Matte and Range sliders, it’s always a good idea to press F3 to take a look at the matte itself. It can be easier to spot and fix holes using the Matte and Range sliders in Matte view. Press F4 to go back to viewing the result.

16. When that’s finished, click anywhere in the viewer to dismiss those sliders. Then hold down the Option key again, and hover the mouse over where her hair passes in front of the greenscreen until you see the Matte Overall, Matte Shadows, Range B, and Range D sliders. Adjust these sliders to either the left or right until you feel that you’ve struck a good balance between the translucence beside each lock of hair and the solidity of the individual strands.

Feel free to continue experimenting with and refining this matte, but at this point you should have a really good key. It’s worth noting that there’s also a set of Matte controls that let you adjust the contrast of the overall matte with Gain and Lift controls, and Shrink and Erode controls to eat away at the matte in different ways (see Figure 7.26). However, for most adequately lit and shot greenscreen clips, these manual controls will yield far coarser results than the sample and adjustment slider controls.

FIGURE 7.26 The Matte adjustment controls

At the end of this process, you’ll still have some holes on the desk, but don’t worry about those now. It’s time to get rid of the tape on the wall. The Keyer controls in Axis provide access to Gmask controls, which can be used as a garbage matte to get rid of anything that wouldn’t key.

17. Click the RETURN button to get back to the main Axis controls, and then click the EXIT button to go back to the timeline. Now you can see the clip in track V1.1 showing through, but it’s completely misaligned and will require some adjustment to fit correctly.

18. Select the background clip in the timeline, and click the FX Axis button to add an Axis control. You’ll be able to make all of the adjustments you need from the FX Ribbon above the timeline.

One of the reasons the background clip is so puzzlingly off is that a mirror was used to extend the distance of the actor from the camera on a relatively small stage. This was done in order to match the distance that an actual duplicate of the actress standing in the next room would be from the camera in order to make the composite simpler. However, you need to reverse the image because of the mirror’s reflection.

19. Move the positioner near the end of the background clip, and click the lock button next to the two scale parameters. Then click the Scale X parameter, use the Calculator to enter -100, and click Enter. The image should be reversed, with the duplicate holding a dart gun aimed at the seated woman.

20. In the final shot, you’ll want to see more of the lab showing through the dimensional doorway, so drag the Position X slider to the right to slide the background over until the podium is just peeking through. Then drag the Position Y control to the right to raise the background plate a bit, cheating the shot to make the alternate more visible. At this point, the result should look something like Figure 7.27.

FIGURE 7.27 The finished temporary composite

21. The resulting composite in the timeline is likely too processor-intensive to play in real time on your computer. So, with the background clip selected, click the Render button in the FX Ribbon, and when the progress bar finishes, play through the clip to enjoy your hard work.

Clearly this isn’t the final effect; the “doorway” effect hasn’t yet been built, the foreground plate has a magenta tinge because of the aggressive spill suppression, and the desk needs some work, but you and your test viewers will certainly know what’s going on, and if the result needs trimming, you can use the Slip tool to change the timing of the duplicate with the dart gun in relation to the seated woman’s reaction. On the other hand, you’ve pulled a really good key that you’ll be able to use later in the final composite.

The Essentials and Beyond

As you’ve seen, the Axis timeline effect encompasses a wide range of sophisticated compositing tools, many of which are shared with the more in-depth ConnectFX compositing environment you’ll see in the next chapter. For this reason, although you’ve used Axis in this chapter to create temporary effects while you edit, there are many situations where you can create finished effects right in the timeline.

Additional Exercises

· In this chapter, you created a picture-in-picture effect for the first portion of the superimposed video chat clip that corresponds to the fifth clip in the timeline. Now use the same techniques to integrate the last portion of the superimposed clip (in which the man concludes his message) with the sixth clip.

· The beginning and ending of the superimposed picture-in-picture effect come up abruptly, so add transitions to the beginning of the first superimposed clip and the end of the last superimposed clip in order to bring the “floating video window” into and out of the frame.

· In the fifth clip, the woman raises her fingers to play the video on the floating window, but the superimposed clip appears to be in front, rather than behind where it’s supposed to be. Edit a duplicate of the fifth clip into a new track on top of the superimposed clip of the man, add an Axis effect to it, and use the Master Keyer to turn the wall in the distance transparent, while leaving the woman’s hand and arm solid, so that her hand appears to pass in front of the floating window.