Anyone have any ideas on how I could do the human dust effect from vaporization, like shown in Steven Spielberg's War Of The Worlds film?

That's a great effect, and would be good if I could do it and make it realistic looking for my fan film. I realized that ILM actually had to use multiple programs to do it... but I'm just wondering if maybe there's a good way to do it on A:M, then I can add other effects to it with other programs.

Here are some reference pics, in case you haven't seen the film:
http://forums.eveofthewar.com/photos/displ...lbum=335&pos=27
http://forums.eveofthewar.com/photos/displ...lbum=335&pos=28
http://forums.eveofthewar.com/photos/displ...lbum=335&pos=23
http://forums.eveofthewar.com/photos/displ...lbum=335&pos=13

Any suggestions?

Thanks

Sure. You could key the character model to hide at a certain frame and then replace it with a "character shaped" particle emitter on the next frame.

rough idea pose slider with gradient and smoke material in chor


[attachmentid=16266]


13beta [attachmentid=16268]

Nice! With a little more work, and maybe the use of powder or flour on cam, that might look pretty good

Thanks folks. If I need any more assistance with it, I'll post again in here.

Sorry for the double-post...

But... I have a question about how I would have to film this.

Say I plan on using this effect for the film.

When I film the people running, and getting lasers shot at them, would I have to have the extras pause in place, so then I would add in the effect with AM, and make them disappear?

or, would I have to film it, and as they're running, I take them out of the scene ?

That would be the one.
Setting up the scene so you can remove the actors easily is a different problem of course.
I would suggest for simplicity you copy and paste the part of the scene they haven't passed into over the part where you no longer want them to be.

The actors probably would pause in place as they get vaporized however.

So... yes answer to both in a way.
A lot will just depend on how you envision the shot.
If you have them pause in place though I think that will take the realism out of the shot.
That might depend a lot on the experience of your extras... which is usually nil.

That depends on whether you're planning to substitute a model to replace the extra's body, or just particles to indicate the "vapor."

I'm going to assume the latter, in which case you'd want the extra to "act out" the vaporization moment, by freezing in place and flailing about.

The easiest way to remove extras is to film the scene twice, once with just the background and once with the actors. (If you're using a moving camera that's nearly impossible.) Once again, you'll probably need a compositing tool like EffectsLab.

Alright.

Well, I just look at this image from Spielberg's War of the Worlds film:
http://forums.eveofthewar.com/photos/displ...lbum=335&pos=23

It does in fact look like before people explode into dust, they seem to pause in their last moments.

So... how do you folks think this would work:

I film the massive group of extras running down the street.
As the tripod unleashes it's heat ray, I have them running towards the camera.
Then, my 2 assistant directors and myself assign certain extras times when they will stop running, and will pause to do their character's final moment, like in that pic above. Then, after a few seconds, I stop filming, take the extras who were just vaporized out, and continue filming the scene... then, in post production, i use AM to make the disappearing/dust effect on the characters... something like in the attachment of the 3rd post in this thread.

Now, when I take the extras out and pause... im probably going to have to manipulate it so only the people who are getting killed are in the camera's view...

I've actually seen something like this done before, using a program called Icarus (now PFtrack from The Pixel Farm).

I'll see if I can dig out the movie file. I've certainly got it on a CD somewhere - I just can't remember what it's called.

Edit: Got it!

I can't remember anything about the clip, except that it was done using Icarus to remove the actors and to track the camera for the "missile" and the dusty body/bones.

@ B Brown - watch the heat ray portions of WotW again and note the absence of people around the victim. In the crowd scenes, the shot was tracked and a garbage matte placed around the victim at the point they are "hit" they continue off camera, but they are replaced by the background where the garbage matte is. The same effect can be approximated in a video editor. You just import the camera track into A:M and at the point the actor disappears, you replace him with a disintegrating model.

Thanks for that Gorf!

So in order to pull it off that way, I would simply film the actors running, and remove them every now and then... and when I import it to AM, I would simply add in the CGI where the actor vanishes?

and what is this garbage matte thing you mentioned?

Thanks

Hey man, this is the internet!

Garbage Matte - a matte or alpha channel used to mask out areas of "garbage" which are unwanted in the final composite.

Beyond that I'll let Gorf explain.

tried a sprite idea...for dust just a test the character should disappear gradually but again this was a test so i just shrunk him and changed his color


[attachmentid=16805]


used the spot particles on the cd

It all depends how cool you want the clip to be. The easiest way to do it is to lock down the camera on a tripod - no camera tracking necessary, but not quite as good looking. You just film the same scene from above, twice. Once with your crowd running down the left and right of the street, then again with your victims running up the middle. Keep a gap between the victims, and make sure they don't overlap the crowd.

Then, you dissapear the victims in your video editor, starting with the one at the back (1), then the one in front of him (2) and so on. When you film, 1 carries on running, and stays a constant distance from 2, who keeps running a constant distance from 3 etc. The reason you start at the back is your victims will run away from their aggressor, who will start with the target closest to him. If he "leads" his heat ray, and tatgets the victim furthest from him first, the ones who are behind the fist victim will seek shelter elsewhere (it's human nature).

To disappear the victim, you need to be able to make video mattes. Essentially, it's an AVI or image sequence of a black blob on a white background, or an alpha channel. When you apply this to your video, it makes a "hole" in the picture that shows through anything on the video track underneath. All you do is put the crowd video track underneath. You'll need to matte out the left and right of your victims for the duration of the clip, so the crowd shows through, too.

Note - these shots are very forgiving. Any artefacts caused by trying to mask out exploded victim will be covered by the dust and the heat ray itself. Also, once the victim has gone boom, you won't hold the shot very long afterwards - less than a second, for sure. People will tend to have their attention on the dust cloud, so any image jitter where the actor is being masked out will be overlooked. Probably.

If you want to move the camera during the shot, you are limiting yourself to one take. This is because you're unlikely to have the equipment available to duplicate camera motion time and time again. In this case you will need to track the camera and use it when you use A:M to create the exploded victim (because the model will need to move with the live action).

I was working on the same type of effect and I used the e-rebuild plugin to break the model apart. Into about 200 shapes. Then created 2 or 3 materials that are particle emitters of different sizes then the worst part dragging the materials down on the 200+ groups created by the e-rebuild plugin. But it does look pretty good just make sure that the particles start out as solids and then get transparent with time.

It would be nice to be able to apply a material to multiple groups easier.

Gary Weaver