Using the Liquify Filter in AE 6.5 to Create Movement

Graham Quince UK ©2005 by Graham Quince and CreativeCow.net. All rights are reserved.

Down load the project files here: Like many of you I'm sure, when I saw that Adobe had included a Liquify filter as part of AE 6.5, I thought "great, well, if I ever need to have a twirl on screen somewhere - oh wait, I have the twirl filter already -- oh well, if I ever need to make part of the screen look bulged -- oh wait, etc..." So I consigned the filter to the part of my brain that deals with junk mail and spam -- well, almost. Then one afternoon when just playing around, I remembered a video I promised to produce with Jupiter in the background. The trouble with Jupiter is it is this enormous swirling gas giant that just looks wrong stuck on the screen unmoving. Everything about the shot was crying out for movement to stop it looking like what it was, namely a still photo. Using the Liquify filter, I took the image and twirled the giant red spot in the direction it was already moving. Not a lot, just enough to make the image change. I reduced the size of the brush and applied the same twirl to the other storms. Then, using the warp brush option, I moved the bands of the planet in the direction they appeared to be travelling in, just pushing them a bit further. A few additional twirls and bugles along those areas of "conflicting gas" and I was done. I'd now created a still of Jupiter a few minutes/weeks older than my original. So still a still. The next step really shows the power of this filter. By setting a keyframe for Distortion Percentage in the last frame of the composition, then setting a new keyframe at the beginning, this time set to 0%, Liquify animates the distortion in shape. It doesn't fade into view, like a displacement map, rather it pulls the image into the distortion. After the success of Jupiter, I tried it on another project. This time, I needed to illustrate slow moving lava coming down a hillside. Before I go further, I need to thank Kathlyn and Jason* from the Cow's photography forum for finding me an image I could use for this tutorial (guys I'm incredibly grateful). Looking at the image, you can see the lava is pouring over a small ledge creating a 'waterfall', or lavafall I suppose. Imagine if the photographer had taken another picture a second or two later, we would probably see the lava pooling at the base of the cliff, pouring down to the left and pushing the cooling rock with it. Using the warp brush again, I pushed and pulled the lava from the very top of the flow, down to the base. I followed that with the bloat brush to create a pooling effect. Using a combination of the twirl, turbulence and reconstruction tools, I did my best to create a sense of rippling on the magified lava, just to remove some of the smoothness that the bloat tool created. Once again, keyframing the distortion to go from 0% to 100% produced a fairly realistic result. The lava does appear to flow. But how often are you going to be asked to recreate lava flowing? If you take a look at the picture, you'll also noticed there's a steam vent in the mid-ground and some clouds in the distance. I used the warp tool to push up the steam, just a small amount, as I have the impression from the photo that this steam is dissipating as it rises. The effect I tried to aim for was to produce a subtle rise while maintaining the overall shape. Finally, there's the clouds in the background. I wanted to move these clouds just a fraction, and the warp tool didn't seem appropriate because of the way it pushes the clouds. In a similar way, the clone option wasn't right either as clouds change shape as they roll across the sky. I didn't want to just move them from one place to the next. Shift Pixels seemed the best option. Shift Pixels create a wake-like effect as you move the brush. Dragging the brush down next to each cloud, displaced the clouds into the brush area, slowly moving the clouds and distorting them in quite a natural way. When RAM previewing and watching the clouds and steam distort over the course of 10 seconds, it's hard to detect movement. It's only if you set your preview to Loop that you can see the movement as the clouds snap back. If you switch the RAM preview to Ping-Pong, this movement becomes very hard to detect. Your eyes concentrate on the 'look at me' lava and accept the rest of the image. Hopefully, I've been able to illustrate the flexibility of this new tool. Liquify can produce silly noses and big chins, but it has uses far beyond that, from lava and gas giants, to selling that matte painting. *lava photo credit: Jdutch- Alluneed productions http://www.alluneedvideo.com

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