particles don't disappear in fog

particles don't disappear in fog

Post by michie » Sun, 04 Oct 1998 04:00:00



I was making this underwater scene, trying to do the dust you always
see floating right in front of the camera and I found out that
particles don't disappear in fog! In fact, in a scene I did earlier
the particles even got extremely colorful once they attempted to
disappear in fog.

Now I've tried to do the dust in steamer, but I can't get it right.
I'm pretty stuck on this, and I want that sucker dust floating in
there for sure. Now don't say I put up 20000 tiny spheres in that
scene - I'll go nuts.

later - michiel

 
 
 

particles don't disappear in fog

Post by Magic Camera » Sun, 04 Oct 1998 04:00:00



>I was making this underwater scene, trying to do the dust you always
>see floating right in front of the camera and I found out that
>particles don't disappear in fog! In fact, in a scene I did earlier
>the particles even got extremely colorful once they attempted to
>disappear in fog.

>Now I've tried to do the dust in steamer, but I can't get it right.
>I'm pretty stuck on this, and I want that sucker dust floating in
>there for sure. Now don't say I put up 20000 tiny spheres in that
>scene - I'll go nuts.

>later - michiel

Its definately a problem we have had the same problem here at Magic
ultimately we ended up compositing the particle matter into the shot.
I have just tried this again and its still happening, little bright green
and white twinkly bits .... i`ll look into it and post back if I find an
answer ....

Cheers -GaRy-

 
 
 

particles don't disappear in fog

Post by Steve Hoefe » Sun, 04 Oct 1998 04:00:00


Yeah, 1 & 2 pt polys are essentailly a post process (Like steamer) so they
tend to behave a little eratically.  Try using Distance Disolve on the
objects panel and turn on Unaffected by Fog.

steve
steven(at)balo(dot)com


>I was making this underwater scene, trying to do the dust you always
>see floating right in front of the camera and I found out that
>particles don't disappear in fog! In fact, in a scene I did earlier
>the particles even got extremely colorful once they attempted to
>disappear in fog.

>Now I've tried to do the dust in steamer, but I can't get it right.
>I'm pretty stuck on this, and I want that sucker dust floating in
>there for sure. Now don't say I put up 20000 tiny spheres in that
>scene - I'll go nuts.

>later - michiel

 
 
 

particles don't disappear in fog

Post by michie » Sun, 04 Oct 1998 04:00:00


Quote:> >I was making this underwater scene, trying to do the dust you always
> >see floating right in front of the camera and I found out that
> >particles don't disappear in fog! In fact, in a scene I did earlier
> >the particles even got extremely colorful once they attempted to
> >disappear in fog.

> >Now I've tried to do the dust in steamer, but I can't get it right.
> >I'm pretty stuck on this, and I want that sucker dust floating in
> >there for sure. Now don't say I put up 20000 tiny spheres in that
> >scene - I'll go nuts.

> >later - michiel

> Its definately a problem we have had the same problem here at Magic
> ultimately we ended up compositing the particle matter into the shot.
> I have just tried this again and its still happening, little bright green
> and white twinkly bits .... i`ll look into it and post back if I find an
> answer ....

How, may I ask, did you go about this? I'd be be happy to just take
my underwaterscene and compositing a layer of floating dust on top of
it,
but the dust should disappear behind certain objects which are close to
the camera, and it should dissolve in the green/blueish fog...
Maybe I can do it with Softimage Particle? I think that takes images
with Z-buffer to composite particles...
thanks, michiel
 
 
 

particles don't disappear in fog

Post by throb (Robert Nederhor » Tue, 06 Oct 1998 04:00:00



>How, may I ask, did you go about this? I'd be be happy to just take
>my underwaterscene and compositing a layer of floating dust on top of
>it,
>but the dust should disappear behind certain objects which are close to
>the camera, and it should dissolve in the green/blueish fog...
>Maybe I can do it with Softimage Particle? I think that takes images
>with Z-buffer to composite particles...
>thanks, michiel

why not render it in LW?
you can use unseen by camera so you can render the objects in front of
the parcticles as a holdout or sorts.
you can render out a B/W sequence of ONLY the fog and then use it as a
z-buffer and have it fade the particles in the comp.

Robert Nederhorst
DIGIT/\L DOM/\IN

 
 
 

particles don't disappear in fog

Post by michie » Tue, 06 Oct 1998 04:00:00


Quote:> >How, may I ask, did you go about this? I'd be be happy to just take
> >my underwaterscene and compositing a layer of floating dust on top of
> >it,
> >but the dust should disappear behind certain objects which are close to
> >the camera, and it should dissolve in the green/blueish fog...
> >Maybe I can do it with Softimage Particle? I think that takes images
> >with Z-buffer to composite particles...
> >thanks, michiel

> why not render it in LW?
> you can use unseen by camera so you can render the objects in front of
> the parcticles as a holdout or sorts.
> you can render out a B/W sequence of ONLY the fog and then use it as a
> z-buffer and have it fade the particles in the comp.

I used the suggestion of distance dissolve instead of fog - this coupled
with a slight particle glow and a good particle motion blur makes for
EXCELLENT water dust... easy as pie.
thanks! michiel
 
 
 

particles don't disappear in fog

Post by Bruc » Sat, 10 Oct 1998 04:00:00



>> >How, may I ask, did you go about this? I'd be be happy to just take
>> >my underwaterscene and compositing a layer of floating dust on top of
>> >it,
>> >but the dust should disappear behind certain objects which are close to
>> >the camera, and it should dissolve in the green/blueish fog...
>> >Maybe I can do it with Softimage Particle? I think that takes images
>> >with Z-buffer to composite particles...
>> >thanks, michiel

>> why not render it in LW?
>> you can use unseen by camera so you can render the objects in front of
>> the parcticles as a holdout or sorts.
>> you can render out a B/W sequence of ONLY the fog and then use it as a
>> z-buffer and have it fade the particles in the comp.

>I used the suggestion of distance dissolve instead of fog - this coupled
>with a slight particle glow and a good particle motion blur makes for
>EXCELLENT water dust... easy as pie.
>thanks! michiel

A question:? is your fog color the same as your background color? I just tried
a scene and found that unless the two are the same color your particles are
still visable. If you need the two different colors try a distance disolve.

Hope that helps.

 
 
 

particles don't disappear in fog

Post by Darren Thompso » Sat, 10 Oct 1998 04:00:00


You can also use a Background Dissolve in the fog settings. This way it
doesn't matter if you have a complicated background or not. The particles
will not appear whilst in the "Fog" area that has been defined.

Cheers

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