Tornado

[Mr Rid]

A test (3 hr setup) just for fun, trying out wind Path which I never had occasion to use before. Can grow a vortex but can't move it around.
http://www.box.net/shared/static/vkbahci4e3.mov
(post processed in Fusion)

Would be nice if there was a spline with control points that the particles could flock and rotate around, then animate the spline.

[tommymamn]

I don't know anything about wind or 1% of the cool effects LW can do yet, but that is an awesome little clip. I love the lightning flash at the beginning too. Very cool!

Tom

[Bytehawk]

maybe this can help


ftp://ftp.newtek.com/products/LightWave/Trial/Content/Wind_Loop.zip

[Mr Rid]

maybe this can help


ftp://ftp.newtek.com/products/LightWave/Trial/Content/Wind_Loop.zip

Afraid Animation Path is an even bigger mess for an undulating vortex. BTW, this example scene is a longer way around to get a tornado. But you run into a frustrating mess trying to animate the handles while maintaining a rotation speed with appropriate falloff to varied diameter of the vortex and vertical rise. The particles dont necessarily adhere to the spline and all the position, scale and rotation values start competing as each handle has to be changed according to the changes in the neighboring handles. There may be some complicated way to rig something but is just much easier to get a controllable vortex with geometry than with particles.

[jameswillmott]

Can you move the scene around the tornado instead? Or by not moving it around did you mean you can't make it flex and bend like a real twister?

[Mr Rid]

Can you move the scene around the tornado instead? Or by not moving it around did you mean you can't make it flex and bend like a real twister?

I mean you run into difficulties trying to move any aspect of the tornado around- flexing or position-wise. Am still trying to get something practical with Animation Path.

[Mr Rid]

OK, there is some nice bug with Animation Path. In three different sims, calculation works when I put pitch and bank values on all the handles except the first one, but it chokes when there is pitch or bank on all the handles. If I Reset pitch and bank on the first Handle, then there is no problem. Reset pitch and bank on all handles except the first one, and calculation works again. And Can not get the sim to work without calculation.

[adrian]

Nice tornado :)

Is the background real? If not, how did you do the clouds and lightning?

[Mr Rid]

The background is timelapse I shot with a video camera. The lightning was shot separately and merged as a 'screen' over the BG. What is interesting is that if you take almost any shot of lightning flashing in the clouds, you can easily screen it over any other shot of dark clouds and it will automatically look like like it is illuminating the right clouds.

I have owned video cameras since '79 and shoot a lot of my own elements for FX work and reference. I have a little library of lightning flashes that Ive used countless times over the years, as well as elements of smoke, sparks, water, skys and whatnot. Most pros would cringe at the idea, but Ive used many video res elements in 2k feature work and they look perfectly fine when scaled and comped right. Sometimes you just need a quick pickup element in post to make life easier and its great to just go out in the parking lot, my backyard or wherever and get my own elements or reference without having to get some elaborate shoot approved with a bunch of gear and crew. And now you can afford HD video for a $1000 (I recently bought an HV20 that shoots 24p).

For instance, we needed a lot of water dripping down the sides of walls and windows for Sin City. So we used a video camera to shoot water dripping down sheets of black plywood and glass to then map on geometry. Looked perfect, and saved a lot of time. A rule of feature FX- if there is anyway possible to avoid doing it in CG, then use a live element.

[Mr Rid]

Animation Path barely working
http://www.box.net/shared/static/k0grd66ygt.mov
wire
http://www.box.net/shared/static/ebkck68drd.mov

[jnddepew]

isn't the tornado too big?

[Mr Rid]

isn't the tornado too big?

Some tornadoes are 2 miles in diameter while others are may be only 50 feet. They vary greatly in width, height, coloration, speed, duration. This is just a rough test to demonstrate a use for Animation Path and there are many aspects of a real tornado missing.

[SonicMotion]

Mr. Rid, I love the way you can get you HV to look, any suggestions for people like me?

[archijam]

Mr. Rid, I love the way you can get you HV to look, any suggestions for people like me?

I think this is the point where you show him your HV's.

j.

[SonicMotion]

I would if I wasn't so embarrassed by them... lets just say lumpy, how do you get your to be more wispy?

[Mr Rid]

I would if I wasn't so embarrassed by them... lets just say lumpy, how do you get your to be more wispy?

First off, HV will not do actual 'wispy' without the all-powerful Distance Between Particle parameter that is missing from LW, and is inherent in other particle shaders, and I keep sacrificing goats to the gods for (well, cats actually, there are no goats in L.A.... hmmm, maybe thats why the gods havent been listening since v6). You'll never get this http://www.box.net/shared/static/urr75v70id.mov where I used a long forgotten Fusion smoke plugin.

But I also get a lot of the hazyness in post with glow, diffusion, edge blur, additional mo blur, twixtor morphing, glass. 2D is your friend. It can save you huge amounts of time over trying to perfect your CG in render intensive 3D world.

But one trick is to apply a basic gradient in the local density of the dissolve channel so the puffballs look hazier where they are less dense. Low thickness, high smoothing. Try to use the least amount of particles vs HV size. Reference real smoke, dust, etc. Dont reference other CG stuff.

The best looking smoke/dust is to use two passes. One using volumetrics and the other using sprites. Combining them in post can make very soft yet voluminous smoke/dust.

The most helpful thing I ever learned in 3D was also the most difficult thing to adhere to, and is not easy to convince people of. But look for ways to isolate each aspect to work on, one at a time- like get your color just right first, then only deal with opacity, then tweak out the Hypertexture, then trial the effect speed- do a alot of low-res or limited region tests with no AA at first. Deal with one thing at a time.

Most people change a bunch of settings at once which can compete with each other and you dont really have control over the result or know what is doing what exactly. This applies to every aspect of 3D. Focus on one aspect of what you are doing, like look at reference of say smoke and notice one particular quality of it, like maybe the tendrily movement. Look for a tool or channel in HV that may achieve this. Just work on perfecting that without worrying about the rest of it. Then move on to the next aspect of the color, or only the density and so on. Get each one perfect before moving onto the next.

And for the sakes of the gods, begin all work at actual scale!!!

[oobievision]

quick question dont tornados form from the cloud down??

[Mr Rid]

quick question dont tornados form from the cloud down??

Growing up in Texas where tornadoes were regularly threatening and from collecting tons of video, I know how they really kinda do whatever they want. They may appear to grow from either end or both, or remain low and wide to the ground (very dangerous as you cant see them coming), or stretch out horizontally for long distances, or appear as several funnels rotating around each other or do other odd things.

Like this weird twin funnel
http://www.stormstock.com/rare%20double%20funnel%20cloud.mov

Bottoms up
http://www.youtube.com/watch?v=rBd0sG559aA

Fair weather vortex
http://www.youtube.com/watch?v=2rK-ctpFBz8&mode=related&search=

[mav3rick]

hey why dont u guys tell dynamite guy to implement distance btw particles in dynamite plugin?

[Mr Rid]

P.S.

I shoot a lot of cloud timelapse and miss Texas weather where the sky was always doing interesting things, thrilling lightning displays, and storms would burst out of nowhere and disappear back into a clear blue sky again in minutes. L.A. is so boring- clear and sunny every day. But I also remember how funnel cloud skys can turn eerily green or violet.

Attached are some of the creepy 'cloud chamber FX' looking mammatus clouds that tornadoes like to drop out of, and some supercells.

[Mr Rid]

The tornado in Wizard of Oz still looks more amazingly surreal and wicked than anything in Twister.
http://www.youtube.com/watch?v=wKrJoih_uCQ

How it was done without blue screens and CG-
http://www.stormtrack.org/library/fringe/oz.htm

[Oliver]

The tornado in Wizard of Oz still looks more amazingly surreal and wicked than anything in Twister.
http://www.youtube.com/watch?v=wKrJoih_uCQ

How it was done without blue screens and CG-
http://www.stormtrack.org/library/fringe/oz.htm
That's always fascinating! I'm happy that I am able to go to classes that teach motion picture history, there is so much to be learnt...

Still I think that the stuff in Twister looked more convincing than the 50 tornados in X-Men or Day after tomorrow. Maybe it's because in Twister they were the heroes and being better directed than the 'general devastation purpose' their following counterparts had to deal with. Not that I did not like them - obviously a lot of work, too!

But: The more FX there are, the fewer time there is to optimize... see Jurassic Park. ;)

Thanks for the links!

Greets.
Oliver.

[JohnMarchant]

Mr Rid, id would love to see a quick tutorial on this. Ive tried several times to do this but it still looks fake.

[Mr Rid]

That's always fascinating! I'm happy that I am able to go to classes that teach motion picture history, there is so much to be learnt....

I really wish I had been spawned about 15 years earlier to perhaps been involved in real FX work, instead of the CG era. Cinefex used to be so fascinating to read about how FX artists had to actually invent everything (like the Oz tornado) creatures and worlds to put in front of an actual camera. Post Jurassic, the only question anymore is, 'which software did they use?'

What little stop-motion Ive done was more satisfying than all the mouse clicking.

I see that many digital artists learn about feature FX and animation primarily thru the desktop computer end. They have little or no experience with actual production, how cameras lenses and lights really work, depth of field, negative space and so on, or with how any of the things they are suppose to be creating in CG actually work in reality. It stuns me how few have ever been on an actual set, or even own or use a video camera for more than taping drunk friends. Tech and spectacle are fine, but you are a much more effective artist when you understand the filmmaking.

[Mr Rid]

Mr Rid, id would love to see a quick tutorial on this. Ive tried several times to do this but it still looks fake.

What are you doing exactly? What does your render look like? I really dont know what else to suggest beyond the above techniques.

[eFFeFFe]

Hi Mr. Rid ... I'm also trying to get the most out of the wind animation path to get a nice tornado, and I'm having problems too, to move the tornado. Particles won't stay properly inside the animation path zone. I'm now trying first to bend the tornado with the handles while it's standing still, second, bake the particle motion and third, move the baked motion as a whole ... But it seems that you can't bake the motion and then move it while the particles still remain hypervoxels, not sure ... any idea ?

thanks,
Mules

[Mr Rid]

Am not sure what you are doing exactly. But yeah, I was only barely able to get animation path to work. Changing one little thing tended to cause a chain of counterreactions. It does not offer the control to handle a picky client.

[eFFeFFe]

indeed ... it looks indeed like it's not that "tweaker friendly" ... buy i'm still trying, can't let it go yet ... What I wandered was, if it is possible to parent the saved motion of particles to a null and then move the null. I think this can be done with cloth dynamics, not sure ... but doesn't seem to work on particles dynamics, no workarounds or something ...

I did get a nice swirl of particles in a slighty bended twister shaped wind animation path, but when moving the whole "setup", the particles flow out of the wind animation path already at the first frames of calculation ... Since I don't need any other cg elements or camera movement, i'm gonna move the camera to get the tornado moving ...

Also tried to model a twister shape; spraying points, then put a few bones in it to bend. But rotating the points properly around the bones didn't seem to work; the points twisted to a single point between bones, when rotating the bones ('m not a bone expert). Tried to get the rotation with several 360° morph targets; could work but not "correction friendly" ... hmmmmmmmmmmmmmmmmm ... :-)

greetings,
Mules

ps: very impressive demo reel!

[Mr Rid]

... What I wandered was, if it is possible to parent the saved motion of particles to a null and then move the null. I think this can be done with cloth dynamics, not sure ... but doesn't seem to work on particles dynamics, no workarounds or something ...

Yes you can set particle Playback mode to Key, then you can parent, scale, rotate, move the baked particles around.

[eFFeFFe]

Oh! ... excellent, ... Lightwave's manual wasn't so clear about that setting ...

Quote :

"The playback mode works with the motion and determines how it will playback. The Normal mode indicates that it will playback normally, starting at frame zero. With Key the motion will be started every time a keyframeis encountered for the emitter. Parent-Key is similar, but uses the parent item's keyframes ..."

... anyway, thanks for the tips !

grtz,
Mules

[Mr Rid]

Oh! ... excellent, ... Lightwave's manual wasn't so clear about that setting ...

Quote :

"The playback mode works with the motion and determines how it will playback. The Normal mode indicates that it will playback normally, starting at frame zero. With Key the motion will be started every time a keyframeis encountered for the emitter. Parent-Key is similar, but uses the parent item's keyframes ..."


Yeah, like everything in LW it could be clearer. But I forgot that Key mode also means the PFX motion will start over every time there is a key frame on the emitter. Never figured out a use for that, but you need to parent the emitter to a null or whatever and animate the null to avoid that 'feature.'

To me, 'Normal' mode would mean you can move and keyframe the emitter like any other 'normal' item. Theres no reason to have the current Normal mode where the emitter can not be keyframed since you would just naturally leave it alone if you dont want it to change... why have a 'mode' for that?

[eFFeFFe]

... mmm ... Maybe it's the "none" or default mode, so you could set it to do nothing ...

I tried to set keyframes on the emitter, just to test, but it didn't do anything !? No restarting or recontinue of the particle motion ... moving the null as you said with key mode worked nicely ...

'm fighting something else now ... the emitter seems to spawn the particles in a patterned way; with even gaps in between. You can see this in the attachment. It's at the ground level of the tornado, further up they get more scattered. Think this is because of the wind animation path. Vibration or explosion settings seem to have not effect anymore when the particles are inside the wind animation path.

... so 'm still tweaking ... :-)

[Mr Rid]

...
'm fighting something else now ... the emitter seems to spawn the particles in a patterned way; with even gaps in between. You can see this in the attachment. It's at the ground level of the tornado, further up they get more scattered. Think this is because of the wind animation path. Vibration or explosion settings seem to have not effect anymore when the particles are inside the wind animation path.

... so 'm still tweaking ... :-)

Not sure. What happens if you set your emitter 'Generate by' to Frame instead of Sec(onds)? (May need to change the birth rate).

[eFFeFFe]

... last problem is solved. By bending the wind animation path handles, the particles got a more random spawn (see attachment).

For the shot i'm creating, I need a tornado you see from a distance, and that's already twisting. The birth of the tornado doesn't have to be animated.
To "fill" the wind animation path smootly, I placed the emitter and the start of the wind animation path below the ground. Made the start of the wind animation path to a smooth cone shape, and the emitter quite smaller then then start of the animation path. By sending the particles in the beginning in an easy straight path into the wind animation path, they seem to respond better to the bending and rotating of the animation path further along.

cheers,
Mules.

[inakito]

Hi there!!!
Your video looks great Mr Rid but can u tell us about render times???

Thanks!

[Mr Rid]

Hi there!!!
Your video looks great Mr Rid but can u tell us about render times???

Thanks!

640x480, 2 lights, 5 pass, average 30 mins per frame across various processors.

[RebelHill]

...without the all-powerful Distance Between Particle parameter that is missing from LW...

Isnt that what the "local density" setting is for/emulates?

[Mr Rid]

Isnt that what the "local density" setting is for/emulates?

Wont come near to same effect as Distance Between Particle gradient in size and blend to make HVs shrink and stretch as they spread out-
http://www.box.net/shared/static/ietmqz76vh.mov

The current DBP gradients dont even work in Velocity, opacity, dissolve, luminosity, color channels as of 9.3.
An examples scene- run viper preview in Scene mode.

http://www.box.net/shared/static/m1sqicrwo4.zip

[RebelHill]

Wont come near to same effect as Distance Between Particle gradient in size and blend to make HVs shrink and stretch as they spread out

yeah... good point... I was only thinking in terms of surfacing for wispy smoke/dust... scaling sprites, or hypertexture parameters based on density.... sure, for getting those density trails... ur right... totally different beast.

Having to use rf on a job atm as it happens... its been a while.

[Mr Rid]

yeah... good point... I was only thinking in terms of surfacing for wispy smoke/dust... scaling sprites, or hypertexture parameters based on density.... sure, for getting those density trails... ur right... totally different beast.

Having to use rf on a job atm as it happens... its been a while.

I just used RF as well for what its best at- spilling paint. RF doesnt really get water consistency. And there are scale issues with small glass-sized or large room-filled liquid sims. Used it for snow spray once but never for smokey things.

Yes,smoke wisps, fire licks, liquid volume to beads or spray is elusive for HV without a simple DBP grad- such a simple addition that would open a lot more possibilities.

[rakker16mm]

Hello Mr. Rid,

I just noticed this thread and haven't had a chance to read through all the posts. It's very timely as I need to do some weather related effects. So thank you for starting this thread. The effect is great by the way. I don't know if this is true in all cases but all the footage I have seen of tornados and from driving across the country, my recollection is that they form further up in the sky and works their way down to the ground. Then when tornados dies it recedes from the ground up. I am really not sure though because I have seen pictures of nearly horizontal tornados.

Any way it is a great effect. I am trying achieve something similar but by a completely different means. I am using several transparent polys spinning around in a spiral using a procedural texture and lots of motion blur. I have seen fog and clouds produced using this technique, but it is too early to tell if I am on the right track. So far I haven't produced anything too exiting.

[Mr Rid]

... I don't know if this is true in all cases but all the footage I have seen of tornados and from driving across the country, my recollection is that they form further up in the sky and works their way down to the ground. Then when tornados dies it recedes from the ground up. I am really not sure though because I have seen pictures of nearly horizontal tornados.

See post #18 in this thread. Tornadoes dont follow a lot of rules and may form and do whatever the hell they want.
60956

60957

60958

60959
Plenty of ref on YouTube and http://www.tornadovideos.net/index.cfm/do/gallery.home

Wedge tornadoes, probably the type of the notorious tristate tornado (longest, fastest heading, and deadliest in U.S.) and others suggest a particularly scary breed of twister that is difficult to see, hovers close to the ground, and may be up to a couple of miles wide.

60960

[Weepul]

See post #18 in this thread. Tornadoes dont follow a lot of rules and may form and do whatever the hell they want.
60956

60957
OK, no way do I believe those two are unedited. Well, maybe the first isn't - no way on the second.

[inakito]

Wont come near to same effect as Distance Between Particle gradient in size and blend to make HVs shrink and stretch as they spread out-
http://www.box.net/shared/static/ietmqz76vh.mov

The current DBP gradients dont even work in Velocity, opacity, dissolve, luminosity, color channels as of 9.3.
An examples scene- run viper preview in Scene mode.

http://www.box.net/shared/static/m1sqicrwo4.zip


Can you not get a similar result as in RF just animating particle weight?

[inakito]

I found the scene with the splines well too complicated to setup... wy not using just a path type wind to guide your particles???

I cannot see any real beneffit on the splines setup...

[Mr Rid]

I found the scene with the splines well too complicated to setup... wy not using just a path type wind to guide your particles???

I cannot see any real beneffit on the splines setup...

A Path wind will not move or undulate as in my example in post #1. The particles only follow a fixed path. An animation path is free to move around but is difficult to control. I have not spent that much time to figure out a better way. It may be better to use geometry. I had a lot of control with a swirling vortex using a cylinder morphing thru a chain of bones in a coil with goals for handles. Have also animated a rope with a chain of bones and point constraints on nulls as handles.

[RebelHill]

I cannot see any real beneffit on the splines setup...

well when ive used paths for particles in the past the advantage has been that u can just model the shape u want to create very quickly and easily rather than having to set up a number of wind effectors and test, and retest, etc, to get the shape/effect ur after.

[Mules]

I also find the setup of wind animation path easy and also easy to tweak (the path); working with nulls.

But from what I have experienced ('m not a particle dynamics expert), once the particles are inside the wind animation path, no other dynamic effect seems to have influence on them. Also the explosion and vibration setting don't have any effect, which would be nice to have some more random effect in the motion of the particles thru the wind animation path.

[rakker16mm]

See post #18 in this thread. Tornadoes dont follow a lot of rules and may form and do whatever the hell they want.
60956

60957

60958

60959
Plenty of ref on YouTube and http://www.tornadovideos.net/index.cfm/do/gallery.home

Wedge tornadoes, probably the type of the notorious tristate tornado (longest, fastest heading, and deadliest in U.S.) and others suggest a particularly scary breed of twister that is difficult to see, hovers close to the ground, and may be up to a couple of miles wide.

60960

Cool. I have a hard time believing #2 hasn't been retouched, but of course that takes nothing away from it, if it is real.

[inakito]

I am just loving this thread, im learning so much. I have tried to save a preview of my simulation bau Lightwave keep crashing... so in the mean time, here goes a first texture test of my Tornado.

Thanks!

[Mr Rid]

Cool. I have a hard time believing #2 hasn't been retouched, but of course that takes nothing away from it, if it is real.

I located the origin of the two questionably knotted tornado images and asked storm chaser and senior meteorologist at the Weather Channel Matt Crowther to verify their validity, to which he says those first two are indeed fake. Tornadoes are so surreal (particularly 'rope' tornadoes) and the lighting conditions that occur around them are so peculiar that many authentic images appear artificial. I've seen bizarre green or violet skies in Texas super cell weather (and hid in a tornado bunker many times). I recorded video off Natl Geo of a multiple vortex tornado where 6 tornadoes are all rotating around each other, and there are endless accounts of the bizarre things tornadoes do so those images seemed as likely as anything

[Mules]

It's been a while, but I still would like to give thanks for the tips in this thread, and share to end result of the tornado shot (has been finalized already for quite some time :-) ). You can view it here
here : http://www.mules.be/data/videos/ue_ident_001/ue_ident_001_qt.mov

Client wanted an agressive looking tornado, so the swirling of the dust is maybe a bit unrealistic. It was quite a hassle also to get all the element into place; the tornado, debris, cracks in the ground, dust clouds ... a lot of render passes and post production, ;-). Text animation was done by another studio.

Cheers,
Mules