Cigarette And Glass Rendering - Clock And Hdri Rendering

[AA74]

Hi all!

here are two still images i did in the last weeks; i will use them for later particle and dynamics stuff;

any advise as usual is more than welcome :-)

cigarette:

http://www.3dartist.it/wip/cigarette.jpg

for this image i can't get rid of the extremely dark edge of the ashtrasher; i used a VEX glass shader;

and i put a sphere environment in the scene to prevent any black reflection, but... still there!

I turned off the micropolygon rendering and i set up both reflections and refractions up to 8 for the ash trasher only; do you think i have to increase these values? I'm already around 8h of rendering...it seems to me to much; ?

http://www.3dartist.it/wip/clock.jpg

for this image i tried an HDRI image...

after 24h i stopped the rendering (it was still far away from finishing);

then i lower down the render times to 8h, using the HDRI only for the background and a light set up with deep map shadows for the clock; also for this image i turned off the micropolygon rendering, and increased the level of detail up to 3...and i can't still get rid of little artifacts on the inner metal objects; ?

Are these render times usual? i know that i can always pre-calculate shadows and/or bake textures;

but i was wandering if there is any kind of settings I'm missing; and finally, what about caustics? did anybody use them in Houdini?

Thanks for any advise and

Greetings from Vancouver BC! :-)

Andrea

[LEO-oo-]

I like the atmospehre of the picture withe clock! Nice work

[Jordan]

for this image i tried an HDRI image...

after 24h i stopped the rendering (it was still far away from finishing);

then i lower down the render times to 8h, using the HDRI only for the background and a light set up with deep map shadows for the clock; also for this image i turned off the micropolygon rendering, and increased the level of detail up to 3...and i can't still get rid of little artifacts on the inner metal objects; ?

Are these render times usual? i know that i can always pre-calculate shadows and/or bake textures;

but i was wandering if there is any kind of settings I'm missing; and finally, what about caustics? did anybody use them in Houdini?

hello andrea.

may i know how big is the size of your hdr map?

i did a couple of render test with IBL. And i notice that the smaller your hdr map the faster the rendertime.

U may want to try to decrease the size of your hdrmap until 200pixel big.

If u just use your hdrmap for diffuse lighting, u may want to use the diffuse convolution function in hdr shop which can be find here http://gl.ict.usc.edu/HDRShop/tutorial/tutorial6.html

hope it helps,

jordan.

[pbowmar]

8 hours is a bit long The problem with the glass shader is, it will give you black where rays don't hit anything. I recommend putting a large sphere around your scene, texture mapped with a background image of some kind, and set it to Phantom render.

Also, set the global level of detail in Mantra (-L .1) down to .1 or so, this will speed raytracing a lot with little loss of quality.

For the HDRI map, make sure you're using .rat format images. If you are, the resolution of the image should not make much difference. There is a command-line programme called "isixpack" that will convert an HDRI-shop "cross" image to a .rat for you.

Hope this helps! Nice images, please post more!

Cheers

Peter B

[AA74]

Hi all!

i'm back :-)

thanks for the replies!

i did some test and here are the results:

the cigarette:

http://www.3dartist.it/wip/cigarette_eta_1.2.jpg

it's strange Peter, because actually i already had a sphere mapped with a landscape texture;

but now i tried with another eta value of 1.2 and it works for the top part of the ash trasher but not for the bottom; so in this image, at the end, i did a mix of both; normally i don't like to do this things but in this case it will be a static shot so it's like a matte painting :-)

I also tried to set-up a lower value of the level of detail, and it works, but just because it will be a static shot i still used a high value

the clock

http://www.3dartist.it/wip/clock_2_tech.jpg

http://www.3dartist.it/wip/clock_2.jpg

I did the convolution and also reduced the size; and for the wall i like the new smoothed shadow, and also the new tint; i think it's more fine tunable; and also the render times went down; Then I decreased the level of detail but i got some artifacts;

in the first image you can see the image just rendered, with the artifacts; the second one it's the image comp together with the previous one

for Jordan: the size of the map i used the first time was the original one from the debevec site(768x1024); then i scaled it down to 192x256

Bye!

Andrea

p.s.: i hope to be able to post as soon as possible the particles for the cigarette :-)

[AA74]

Hi!

I finally added particles both to the clock and the cigarette;

here are the results; for the ash tray i did a drop done with a particle simulation and rendered with metaballs;

any suggestion is always welcome!

Especially for the metaballs, is there a way to stretch them based on the direction? At the end of the simulation they pop a little bit because the particles are getting far from each other so the mesh is not continuous;

clock + crack

http://www.3dartist.it/wip/AA_2007_05_01-10-18.jpg

ash tray + drop and smoke

http://www.3dartist.it/wip/AA_2007_05_01-45-23.jpg

http://www.3dartist.it/wip/AA_2007_05_01-46-22.jpg

http://www.3dartist.it/wip/AA_2007_05_01-49-14.jpg

to see the animation: (sorry it's in the reel, i didn't a separate file)

http://www.3dartist.it/video/AA_2007.mov.rar (189MB) - mov

http://www.3dartist.it/video/AA_2007.rar (42MB) - wmv

p.s.: the ash tray is at 1:42

the clock is at 1:06

Greetings from Vancouver!

Andrea

[paint]

Very nice!

Edited June 11, 2007 by paint