Feature

Requirements: NewTek Flyer, Control Tower, ImageFX

dding cool fog and nebula effects to your video clips doesn't have to be a complicated and time-consuming affair. Visual Inspirations Control Tower software package for the NewTek Flyer has a number of nifty features which, working with ImageFX (from the nice folks at Nova Design) allow you to accomplish this task with ease - although in a perhaps strange and unorthodox kinda way.

I got the idea for this effect one fine sunny day outside as I glanced up and happened to wonder: "Say - is that sky the right shade of blue to allow for good chroma compositing? What would the clouds look like in the final clip?". Being experimental sorta guys, we decided to find out. What we learned was yes, in fact you can use the sky's blue as the key color in a composite. The bonus was discovering just how cool the clouds look in the finished clip when you're done.

Here's a product tutorial for Control Tower users which will walk y'all through the steps involved in creating this way-cool video effect. This is actually a combination of 2 routines in Control Tower (hereafter called CT): the time lapse record function and (of course) the blue screen composite routine.

Naturally, the first thing we need before we can even begin is footage of some moving clouds. So - go get some! Of course, the best results will be had on those days when the sky is neither overcast nor cloudless (well, duh). Set up your tripod outside, point your camera at a likely-looking patch of sky (unobstructed by power lines 'n such) and tape, say, about a half-hour's worth of footage.

Next, take your tape back inside, load it up on your VTR, and then boot up your Flyer system and Control Tower. Go to the CT "Flyer Menu" program and select the time lapse record function. CT will first ask if you need instructions. Then, CT will ask for the compression quality setting you desire for the clip you're about to create. Normally we'd want to select Hi-Quality 5 for best results. Next, CT will ask which video input to take the feed from. Since we recorded to tape we'll be reading it off of the VTR on input 2. However, you could use a live feed from a camera if you're close to a window or somewhere else where you can get to the footage you want easily.

There are two methods by which CT grabs images from the feed, and the highly descriptive titles for them are Method 1 and Method 2 respectively. Method simply refers to the way the software speaks to the hardware. While Method 1 is faster, it doesn't work on all computers - so to be safe let's choose Method 2 - it does work with all machines.

After this CT will prompt you for the name of the time lapse clip that you wish to save out. Then you will be asked how many total frame grabs to make and the number of frames to get per grab. The default on this last item is 1, but if you don't want your clouds moving too fast you might want to put a larger number in here so that each frame grab will be shown for a longer period of time. We encourage you to experiment and discover which results work best for you - for now we'll grab in a 10-second delay. CT will then ask you to input the time delay between frame grabs. This will likely as not be dependent on how fast the clouds were moving by that day - again, a bit of experimentation will probably be in order. Again, for now we'll go with a 10-second delay. After this step you'll be ready to begin the grabbin'. Make sure the tape is rolling (or your camera is pointed at the clouds and recording if you're doing this from a live feed) and click "OK".

Now CT will control the Flyer as it goes through the process of time lapse frame grabbing to create your clip of moving clouds. Once this is done you'll have a Flyer clip of, well, moving clouds.

Next you need to figure out what clip or image you wish to overlay your clouds onto. For our example we've used one of the images from the Corporate Video Backgrounds collection: a picture of Washington D.C. in the dark (a fitting setting for such a place).

After the grabbing is complete, you'll want to go and load up ImageFX, then go back up to CT's "Flyer Menu" program on the Flyer screen and select the IFX_CLIP_TO_CLIP option. As before, Flyer Menu will ask if you need instructions - you can bypass 'em for now since we'll be going through all the motions here anyway.

Select the Composite_Blue_Screen script from the file requester which appears. After that you'll select the clip you want to process - in this case it's the moving clouds clip we just created. Next you can select a range of frames to process. It defaults to all but you can select a smaller range if ya want.

Then you'll be prompted to provide a new name for the file which will be created when alla this stuff is done. Next you'll choose the compression scheme to use.

Now CT flips you over to the ImageFX screen and asks you to select what type of background to use - image, sequence, or Flyer Clip. In this case we'll be using a still image (of Washington at night). We're almost done! Next we select the color for the cinematte. You have two options: blue or green. Since the key color of the sky is blue (well, unless you live in a highly industrial area), we'll be choosing blue.

Now CT does the rest auto-magically. It'll go through the clip and cinematte it for a blue key color and combine the cloud clip with the still Washington image and save it out with the name you provided earlier. When you're done you'll have some interesting fog effects - and you didn't have to go into LightWave and twiddle around in there for hours to get 'em either. Cool, huh?

This is just scratching the surface of nifty and neato-keen stuff you can do using this trick. There's all kinds of possibilities. Need helicopter footage but can't afford to charter one? Hey - wait for one to fly by and then just rip it off. You can even create your own UFO hoax - toss a customized frisbee up in the air when an airliner is flying by overhead. Maybe even set up a trampoline and catch some footage of your kids and then cinematte them bouncing into outer space (an attractive offer to some parents). Whatever.

So there you have it: How to use Control Tower and your friendly local sky overhead to create cool fog effects. If you come up with some other applications of this idea, Email Us and tell us all about it.