SEPTEMBER 26, 2001
by Kevin Schmitt
This week we're going to start taking a gander at RE:Vision Effects' suite of video and effects plugins by doing two, two, two reviews in one. Why double up? Well, According to RE:Vision Effects' own literature, "ReelSmart FieldsKit is a great companion to other ReelSmart modules such as Twixtor and Motion Blur," so we're going to see how that claim measures up by using the After Effects versions of FieldsKit and Motion Blur in tandem.
I must admit that I was a bit skeptical at first that these products would, or even could, work as advertised. After all, getting clean, progressive-scan plates from video source and adding motion blur to a comp as needed were two of my personal holy grails. As these are two of the main selling points of FieldsKit and Motion Blur, respectively, I wondered if they could really do the job. I don't want to spoil the ending, but after only a couple of weeks FieldsKit and Motion Blur have already changed the way I approach compositing tasks, and I can think of at least a dozen projects I've done in the last year that would have benefited tremendously from these tools.
ReelSmart FieldsKit: What it does
The star of the bunch is the Deinterlacer plugin. Deinterlacing is a tricky process because what you're really asking the software to do is throw away half of the frame and re-create what was thrown away through interpolation or doubling of the remaining field. And at first glance, it appears that FieldsKit's Deinterlacer doesn't do any better job of handling interlaced footage than After Effects; however, it begins to set itself apart once you blow by the default settings and dive into the other options. According to RE:Vision Effects, the Deinterlacer "uses adaptive motion techniques and clever models for deinterlacing." In plain English, it goes way beyond simple upper frame and lower frame field order to allow the user to control every aspect of the deinterlacing process. This control is accomplished by breaking the process down into four main functions: field order, timing mode, fill method and motion masking.
Field order is the standard selector that most of you are probably familiar with, letting you select upper or lower as the dominant field. The timing mode options allow you to choose whether one or both fields in a frame are interpolated, which in turn affects the duration of the clip. The fill method provides a choice of several interpolation options, such as duplicate, blend and nearest neighbor. Perhaps the coolest feature, motion masking, actually analyzes the motion of the clip and only selects the areas of the image that are in motion for interpolation while leaving the static areas of the image intact. This function is especially handy for locked-down shots where objects are in motion against a non-moving background.
The other two FieldsKit plugins, Pulldown and Reinterlacer, are nice inclusions as well. The Pulldown plugin provides some advanced settings for turning 24 fps film clips into 30 fps NTSC standard clips (or vice versa). The formula for pulldown basically turns four frames into five, so the ReelSmart Pulldown plugin lets you choose between numerous settings for determining which of the four frames in a five-frame sequence remain whole and which get split. The Reinterlacer plugin adds several output types to the normal upper field/lower field dominance options.
ReelSmart FieldsKit: Limitations
Also, I didn't find that the Reinterlacer plugin gave me a better final product than the normal field rendering options in After Effects, though admittedly I am looking at them with more of a compositor's eye. I suspect that editors would find the Reinterlacer to be a very able companion to the Deinterlacer, as the timing options in each work in tandem to minimize field rendering quality issues when re-outputting edit-only footage from NLE software.
ReelSmart Motion Blur: What it does
And it does it very well. The plugin's power lies in its ability to compare frames of a sequence and determine what has changed over time, and then applies a very convincing blur to the image. So what does this mean in reality? I can now render out objects in 3D once against a neutral background with no motion blur, composite the rendered layers against a background and add motion blur as the last step. This frees up every layer in the composite to be changed as often as you like with no re-rendering of any source images. Here's an example.
This is a comparison between a frame from the original comp (top), the same frame from the new comp without the Motion Blur plugin (middle) and the same frame from the new comp once Motion Blur was activated (bottom).
But there are a few bonus uses as well. In addition to adding motion blur, it can also remove motion blur. The effects are subtle, but it can compensate for footage that has a little too much blur on moving objects. Another feature is that you can use the motion from one layer to blur another layer, resulting in some cool transitions and effects. The last bonus is that you can use Motion Blur in place of After Effects' Frame Blending option to interpolate frames of a time stretched clip, often with superior results. There are some great video examples of these other features at http://www.revisionfx.com; I recommend checking them out.
ReelSmart Motion Blur: Limitations
How ReelSmart FieldsKit and Motion Blur work together
So I tried the compositing the shot again, this time using the FieldsKit and MotionBlur plugins. I brought in the live action peanut shot and interpreted it using FieldsKit's motion masking options, fiddling with the interpolation settings until I had a cleaner plate than before. So far, so good. Then I rendered the CGI peanut and shadow separately without motion blur turned on, which saved quite a bit of rendering time. Getting better. Next, I time compressed the live footage to be one second shorter than the original source, but instead of using After Effects' frame blending, I opted for the Motion Blur plugin to smooth the frames. The results were subtle, but slightly better than frame blending. I then composited the CGI peanut and shadow over the live footage, then nested that comp in another comp, at which point I added the Motion Blur plugin to the entire comp. The result: the finished clip looked almost identical to the original, with the background being a lot cleaner and a with a little smoother motion. The main difference is that I could change any of the elements without having to re-render the CGI peanut elements. Once I crunched a few numbers, I found that I could have saved between 8 and 10 hours putting this particular comp together had I used the ReelSmart plugins originally. Nothing to sneeze at!
The bottom line
The two products are available for Macintosh and Windows for $89.95 to $134.95. FieldsKit works with After Effects, Final Cut Pro, Commotion, Premiere 6, Combustion and other After Effects plug-in compatible programs. Motion Blur works with After Effects, Final Cut Pro, Commotion, Premiere 6, Combustion, and other After Effects plug-in compatible programs; Avid, Shake and Discreet Spark compatible programs. For more information, visit http://www.revisionfx.com.
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Kevin Schmitt has been a working with just about every aspect of digital design since before it was called digital design. An award-winning multimedia producer, artist, and animator, he is currently the Digital Design Director for StudioAPCO, a creative shop housed at a communications firm in Washington, D.C. By all means, drop him a line at [email protected].