Could someone give me an idea of how this shot could be reproduced in AM? This was not rendered in AM.

This is what I've got so far. As you can see, not quite there. The ground is darker, the sides of the model are not uniformly lit, the top of the model has too much light falling on it. I've played around with the settings quite a bit, but just can't seem to find the right combination. This is my first foray into any kind of custom lighting.

Model: Diffuse color: White
Diffuse Falloff: 70%
Ambiance Intensity: 0%

Light for skylight rig: Type: Bulb
width: 316
Falloff: 30,000 (setting of the light as imported)
Intensity: 15%
Attenuation: 100% (don't know what that does)
Options: Diffuse: On
Specularity/Volumetric: Off
Cast Shadows: On with 1 ray cast and darkness at 97%

Ground: Diffuse color: White
Diffuse Falloff: 150%
Ambiance Intensity: 0%
Options: Front Proj. Target: On
Flat Shaded: Off
Cast Reflections: On
Cast Shadows: Off
Receive Shadows: On

No other light sources besides the skylight rig.

Please give me feedback, any help is appreciated.

What you have there looks like a model from lightwave , but we can get the same basic results from it.

All you have to do is put your car into a blank choreography, then insert 9 or more kleigs, 8 in a circular path and the 9th above, with 100% shadows, 2 ray casts, and all other properties set for default values. Make sure that the kliegs have a falloff that is half way to the car, and that all the lights have the same amount of brightness.

Radiosity Setup
these are the average settings i use for all my radiosity shots (although you can adopt your own if you want)

Photons Cast: 100,000
Sample Area: (you need to download the radiosity calculator for this)
Photon Samples: 100
Intensity: 100%
Max Bounces: 15
Caustics: OFF
Final Gathering: ON
Samples: 200
Jittering: 20%
Precomputing Irradiance: OFF

For your surfaces, just make everything the default, (notset), value for everything. You dont need to touch any of these values... that is if you want the matte white render. Oh and for radiosity you never use pure white, red, blue, yellow, so on, rather you can slightly desaturate and lower the brightness of your colors. It gives them a realer look.

Now, lightwave gives you an incredible radiosity render. They aint messin around with their stuff... it's all very much controlled by incredibly advanced computer algorithms and things of that nature. They can get radiosity looking as clean as real life! no noise or artifacts at all! but... allass, i dont have a few thousand $$$ to throw at light wave. lol. Now the render i did of my car sort of came out like that, but i need to adjust my kleig brightness scales. In the render you provided it looks like a very very pale blue, so if you want that exact effect you may want to make it an almost white blue color for the light diffuse color.

This is how light fades after falloff. If it is set to 100% light will fade to black after a distance. If attenuation is set to 0%, the light will never fade, and will continue to cast light forever. Or at least i think that's what it is. i could be wrong.

Really appreciate the in-depth reply Dan, thank you.

As I mentioned, lighting is new to me, so please bear with me. Where are the settings for the photon values, sample area, etc?

Also, what difference does it make when you have two ray cast instead of one?

When you do renders with one ray you get a very noticable banding on light. With 2 ray casts the banding is destroyed, and you get a very realistic shadow. You should have your renders at a 4x4 or 16 multipasses. Now you have 2 rays in each pass and 16 passes, that adds up to 32 ray casts for each light.

In the choreography properties there is a setting called radiosity. Just turn it on, and all those values should be there. If they are not, you need to go to the animation master options and make sure you turn on "Show advanced options" in the "Global" tab. If you are new to radiosity i would direct you to the radiosity tutorial topic. Just click here. The sample area calculator, and some very helpfull stuffes are in there.

The first pic is with one ray cast, and the second is with 2 ray casts (NOTE: i forgot to turn the bulb to 100% darkness shadows, which, even though i dont have it on at the moment, is a must for radiosity.)

eric,
with the light setup in your initial post, I would set the shadow darkness to 100% and then render it with 16 multipass. When using multipass, A:M will jitter the light inside of its width automatically giving you softer shadows

You don't need radiosity to get the effect you were showing. The lighting effect you showed is called ambiance occlusion. This is done with a full skylight in A:M.

Use a full skylight rig. Your skylight rig is not complete. It is missing a lot of lights. Start with one of my Skylight Rigs. The 20 light rigs is a good one. Do not remove any lights from it.

Set your skylight light to cast 2 shadow rays. With only one shadow ray, the shadows are too sharp which produces shadow banding. And, also, The shadows will be attenuated with distance. With such huge lights, this will be almost like if you didn't have shadows. With more than one ray, the shadow rays are stochastically sampled on the lights and are not attenuated with distance. This is what you need.

Set your shadow darkness to 100%. Let the lights and the shadows do their illumination work.

Render with 9 or 16 passes multipass. This will get you nice antialiased render and will also multiply the number of shadow rays as Dan explained.

I imported one of your skydomes... but the models are just a bunch of bones. Do i have to add the lights to the model or something?

never mind... i found out what i had to do. This is pretty cool! how do you make a bone accept a light in an action? MAN! there is so much about this program that i dont know about. lol.

This is a comparison shot i made... more of a learning thing for me... but here are the results. I used yves 25 light rig for the test with no radiosity.

Fantastic render Dan.

I love it when someone posts a render from "some other" application... and within a very short time... AM results appear that are as good if not better.

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You can add lights to models very easily. I think you just drag them in. By default they have a bone. You drag in a light and it has a bone... it must... only way to move it around.

That's how you add head lights to a car... or a bulb in a lamp.

So... then you could create a model with just a light only. Create an action for this "light model"... that is how those skydome thingies are done.

Don't quote me on this.



Vernon "!" Zehr

I figured it out... he just used the constrains "translate to" and "aim at" to put those lights in their place... i just didnt know you could do that. i need to read some manuals. lol

First off, thank you all for the great input and valuable info. It'l take me a while to digest and apply everything I've picked up tonight.

Dan, I get the idea of rays now. Your pics clearly show the banding you described. It follows, that render times will increase quite a bit with more rays cast, but that's the trade off for better renders Great renders. Could you post a screenshot of the model and skylight placement like I did for my render above. I must be doing something wrong with the scale and placement because my render is still not quite right.

William, I've already got multipass set at 16 and have now turned shadow darkness to 100%. Will render again with all the input I got and post as soon as it's done.

Yves, the skylight rig I used to render the pic above is your 8 light rig if I'm not mistaken. For the next render, however, I will follow your advice and try the 20 light rig with 2 rays cast.

The scale of the rig and it's height over the model seem to have a great deal of impact on the composition of the render. I saw no reference pics or description of scale and distance to the target model? Should the lights be engulfing the model? Should they touch the ground plane or should they hover some distance over the model?

If you look at my third pic posted above, you can see how I set up the original rig in regards to scale and distance to model. Does this look about right?

I am rendering with new settings as I'm writing this and will also post a screenshot of the skylight placement.

Please look it over and let me know what you think.

If I compare the two renders, I find that the first render with the skylight rig higher above the model and not touching the ground plane is overexposed on top. The second render with the skylight touching the model and groundplane overexposes the model on the sides.

Trial and error with this can get pretty time consuming since every render with 2 rays takes about 45 minutes. Yves, where do you place your skylight rig in relation to the models to get an optimum image? A screenshot of the size and placement would really help.

Just drop the skylight in the scene. Don't move it. If your ground floor is at y=0 then this should be OK. If you moved your ground floor, then move the skylight rig the same place too. By moving the skylight rig, I mean the Chor->Skylight->Transformation->Translate coordinates should be the same as those of your your ground model.

Scale the skylight so that no lights touches the model. Scale all X, Y and Z axis the same factor. In your wireframe, you didn't scale on Y the same as on X and Z so your skylight rig is flattened. It looks like your X and Z scale are right but you must also scale the same factor on Y now. The sky is modeled as a hemisphere of lights. That is light is coming from all directions over the sky. Not just from above. Your own remark "evenly lit from all sides" from your attached picture should give you a hint. Evenly lit on all sides requires even distribution of light all around.

Thanks Yves, I'm gonna do another render with that in mind and post when done.

I just figured out one of my mistakes when using your skylights - I used to drag the rig from the PWS into the chor window. Now I drag from the object folder to the chor folder in the PWS only and the rig pops right into place. Ok, time to render.

I did some small renders with Yves's sky light setup and models from the hash community. I was quite happy with the results.

The Ogre is the best example. The color is not white but RGB(223, 231, 236). This gives it a slight blue color. I also changed the intensity of the sky light lights to 8%, 100% darkness and 2 ray casts. At most these renders are taking about a minute per pass, though they are relatively small.

I have decided to rerender some of the first renders to show the difference.

That's really great for comparison Matt. Thanks for posting those. With all this info, I think it won't be hard to have this thread put on the links page.

I am producing several renders myself right now and will post as soon as I've got what I feel works best for comparison to the original shot above.

Yves, could you tell me about "Front Projection Target" and "Flat Shaded" in the options section of the skylight? I read in a recent thread that for a white render the Target should be set to "On" ? What effect does that have? Come to think of it, I believe the Target "On" was in reference to the ground plane.

I don't follow you here. There are no options in my skylights. They are just models, action and lights. I don't know what you are refering to.

Sorry to be unclear. Here is a pic of what I am talking about.

Also attached another render comparison. I think tweaking with the settings is all I need to do now. Thanks so much for everyone's help, and especially to Yves for the skylights and explanation of how to use them.

One thing I noticed:

Your model is really big in the skydome. Make the model about the size of a Hot Wheels car under an umbrella so that it is illuminated evenly accross the model. The umbrella being the skydome.

Other than that, everything looks good with the lighting. Oh, and turn the front wheels to point outwards like in the other shot (adds a certain feeling to car pictures).

I wonder if there's a way to get some sort of High Dynamic Rang Lighting in the shot. That would make it easier to obtain global illumination rather than using a light rig.

Thanks for the Hot Wheels comparison, that's something I can easily visualize. Next shot will be with the model more refined and wheels pointing outward

Could you expand a little on the concept of "High Dynamic Range Lighting?"

Hope to see it soon. at the moment the top right one looks the best.

Made another render with the lighting setup. A dog named gir.

Yves, is there floating point opperations in the calculation of light on A:M? Right now i have your light rig set up, an environment dome (just because i dont know how to use the environment maps), and a sun light, but the reflection of the sun on the car paint is, compared to what it should be, very dark. Is there anyway to increase, or turn on the floating point operations in animation master so that the sun reflection on the car would be seen as pure white and actually above 255,255,255?