Harnessing Electricity
Transcription
Harnessing Electricity
Tips N Tricks More available at artbeats.com Harnessing Electricity Bending the new Artbeats electric effects collections to your will. by Chris & Trish Meyer, Crish Design Long-time users of Artbeats footage are probably familiar with their ReelExplosions and ReelFire collections, which were based on combustible themes. So after you’ve blown things up and set them on fire, what do you do for an encore? Apparently, electrocute them. Artbeats has now created a series of collections – Electric Arcs, Lightning Arcs, Lightning & Clouds, Lightning Strikes, and High Voltage Scenarios – in partnership with kVA Effects (www.teslacoil. com), who are in the business of creating high voltage and theatrical lightning effects (think 60-foot electric arcs shooting through the air) for video, film, and live presentations. Of course, the resulting clips are ready to be used as-is, full-frame. But you can really extend their usefulness with a few blending and distortion tricks, which we’ll outline here. Figure 1a Figure 1b Out of the Black Most of these clips were shot against a black background, and are just begging to be composited on top of other footage to add electricity and mayhem to a scene. In the Tips N Tricks article Managing Transparency Part 1, we discussed a number of ways to creatively blend clips shot on black; we’ll give a thumbnail review of those techniques here. First off, the thing not to do is to reach for a luma key effect to drop out the black background: This almost always leaves a black fringe around the action part of the shot. Some of the clips – particularly in the Lightning Strikes collection – are provided with companion matte movies, which already contain alpha channel (transparency) information. They can be combined with the original color clip using the Track Matte feature in Adobe After Effects, an Image Mask in Apple Motion, or other similar techniques. If the clip you want to use doesn’t have a matte supplied, or if you want a more transparent look than the matte provides, apply an “unmult” type effect that makes the black areas transparent, full-strength white or colored areas opaque, and those in between semi-transparent. The most famous of these effects is Unmult, which comes with Knoll Light Factory; another option is the free Xmult plug-in from FAN Development (www.fandev.com/xmult.html). Figure 1: Most of the high voltage clips are shot against black (a). If you use a luma key to remove the black, the result is often unpleasing edges, including a dark fringe (b). An unmult-style plug-in creates a nicer alpha channel (c), or you can use blending modes such as Add to make the electric arc interact with the scene (d). Clips from Artbeats Lightning Arcs and Gears. Figure 1c Figure 1d page 1 Tips N Tricks More available at artbeats.com Beyond just creating transparency for an overlay effect, you can use blending modes to make the high-voltage clips interact with the footage underneath. As they were shot on black, try Add, Screen, Color Dodge, and other similar modes to add illumination to a scene. Conversely, to have the flashes in the voltage footage reveal portions of another shot, use Multiply, Linear Burn, or similar modes. Figure 2a Figure 2b Figure 2c Logo Treatments Several of the high voltage clips are generated from or around distinct shapes, such as a circle or rectangle. As this is the general shape of many logos, these clips become candidates to electrify your logos. The trick comes in matching the shape and size of the electric effects to the logos. Let’s tackle circular shapes first. Clips EAR101 through 106 from the Electric Arcs collection all come from a central circular shape; just center them over your logo and apply using a blend mode like Screen. What if your logo needs to appear larger than the original shape? You have a few options. The simplest is scaling up the Electric Arc clip to match – but too much scaling can result in a degraded image. If your final output is standard definition video, you can see if the corresponding high-def clip is available from Artbeats.com; that will give you a lot more pixels to play with. Another option is to use a high-quality scaling plug-in, such as Digital Anarchy’s ReSizer (www.digitalanarchy. com/resizer/resizer_main.html). If the logo has an oval shape, scale the Electric Arc clip differently in the X and Y axes as needed. A more creative approach is to use a distortion plug-in – such as a bulge – to inflate the center of the Electric Arc clip to match logo, while keeping the rays beyond the center at their original size. This gives you more options, such as scaling down the Electric Arc clip overall to form a tight set of arcs around the logo, but still bulging the center larger to match the logo. If the center is overwhelming the logo, mask it out, or select an alternate clip (such as EAR106) that has the weakest center. Figure 3a Figure 2d Figure 3b Figure 2: “Flash” clips – such as LCL125 from Lightning & Clouds (a) – can be used over ordinary footage (b) to either overexpose it using blending modes such as Add (c), or reveal it using modes such as Multiply (d). Background clip from Lifestyles -Mixed Cuts. page 2 Tips N Tricks More available at artbeats.com Figure 3c Figure 3: Many of the clips in the Electric Arcs collection radiate from a circular center (a). To make these interact with a circular logo, use a blending mode such as Screen and either scale them up to fit (b), or use a distortion effect such as a bulge (c). Background clip from Artbeats Liquid Abstracts. Masking can also help tame the edges when centering an electric effect over a logo. Whereas the arcs in the EAR101-106 clips do not quite reach the edge of the frame, the very cool HVS114 clip in the High Voltage Scenarios collection does reach the edges – which can look a bit funky if you want to scale down the clip and use it less than full frame. Create a circular mask around the source of the arcs, and increase the mask feather parameter to create a soft fall-off. If the amount of feather you like makes the mask now reach beyond the edges of the image, either scale down the mask shape, or in After Effects use the Mask Expansion parameter to reign in the mask’s size. What if your logo has a rectangular shape? It so happens that a couple of the Electric Arcs clips – such as EAR107 and 138 – flow around a rectangular outline. Again, you can scale and mask as needed to fit them around your logo. Figure 4a Figure 4b Once you’ve got the general idea down, you can use other distortion effects to create different looks. For example, many of the clips in the Electric and Lightning Arcs collections have electric arcs emanating out from a central point. Place them in front of or behind your logo, and use distortions such as twirls to bend the arcs around the logo. You can also take some of the full-frame arc clips from these collections and compress them into cool underscores or lower-third bars by reducing just their Y scale. Figure 4c Figure 4d Figure 4: Electric arcs – such as LAR125 from Lightning Arcs (a) can be twirled to wrap around circular logos (b). Full-screen arcs such as EAR114 from Electric Arcs (c) – can be scaled to form underscores or other bars (d); if you use more than one copy, offset them in time so the bars look different. Full-screen Background clip from Artbeats Liquid Abstracts. Bottled Lightning We’ve suggested just simple distortion effects so far; more complex effects allow more complex results. One of our favorites is Reshape in After Effects. You create two mask shapes for the layer to be distorted, and it takes the content contained within one shape and warps it to fit inside the other shape. If your first mask shape is the same size as the high-voltage clip, you can use it to appear to fit this clip inside an object in an underlying piece of video. You can also do more complex reshapings, such as taking the Jacob’s ladder effect in clips EAR 122 or 123 from Electric Arcs or HVS117 from High Voltage Scenarios and warping it to follow along a pair of TV antenna “rabbit’s ears” or any other pair of wires. page 3 Tips N Tricks More available at artbeats.com Figure 5: More complex distortion effects such as Reshape in After Effects Professional may be used to fit arcs (a) into other shapes (b). Jacob’s ladder effects (c) can be stretched to follow television rabbit’s ears (d). Video clips from Artbeats Electric Arcs and Liquid Abstracts; spaceship and rabbit ears from Classic PIO Partners Nostalgic Memorabilia and Classic Televisions & Gadgets. Figure 5a Figure 5b Figure 5c Figure 5d Distortions can work both ways: In addition to warping electric arcs to fit into other footage, you can warp other footage to fit into one of the more complex high-voltage clips. For example, several of the clips in High Voltage Scenarios feature lightning striking a satellite television dish. The dish Artbeats shot is nicely generic with no brand logo; if you want to add your own brand logo, consider gently warping it with a spherize effect to better fit the curve of the dish. At Your Fingertips A few of the clips in the High Voltage Scenarios collection show electric arcs extending from a person’s fingers. What if you want to add electric arcs to your own footage? With a little work, you can easily recreate this effect. First, select one or two clips with arcs that come from a central point, such as EAR113, 119, or 139 from Electric Arcs, or LAR132 from Lightning Arcs. If the arcs are not coming from the exact center of the footage, move the clip’s anchor point to line up with the source. Then track the fingers (or nose, or whatever object you want the arcs to come from) using Adobe After Effects Professional, Autodesk combustion, or Silhouettefx Roto. Apply the tracking data to the Artbeats clips so that they follow the fingers in your footage. Finally, scale and rotate the clips to taste; if your program supports 3D space or has a 3D plug-in, you can rotate them in 3D to make them appear to shoot out at almost any angle you like. Again, consider using a blend mode such as Add to make them seem to illuminate the underlying scene. Figure 6a Figure 6b Figure 6: The dramatic electricity-from-fingertips clips in High Voltage Scenarios (a) may give you ideas for your own composites. Grab a couple of clips from Electric or Lightning Arcs, and use motion tracking to make electricity flow from the desired points in your own footage. Background clip from Artbeats Desktop Technology. page 4 Tips N Tricks More available at artbeats.com Zooming Out There are but a few ideas of how to employ the neat clips in these collections. Note that many of these clips were shot in super slow motion, which means you can cleanly speed them up to match the pace that works best for your job. Also, a good number of them are available in high definition versions; if your project is in standard definition, having the high def clips around gives you extra flexibility, such as the ability to “zoom in” on a portion of an overall shot without having to scale the clip past 100%, which would otherwise degrade it. Have fun, and remember to stay grounded! Chris and Trish Meyer are the founders and owners of Crish Design, an award-winning motion graphics studio that has created a wide variety of work for film, broadcast, corporate events, and special venues. They are one of the original development sites for After Effects, and have two books currently in print: Creating Motion Graphics and After Effects Apprentice. page 5