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ikep2008

Auto Light with Ambient Occlusion ok for animation?

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I was wondering what are common practices in lighting for motion graphics. With my animations in C4D have been just using the built in autolight with ambient occlusion with decent results, however I feel like I maybe limiting the best results somehow. Setting up lights never seems to look right especially when the camera moves through a scene with multiple objects (how to light them all naturally is frustrating) I would like to hear about what lighting techniques you guys typically use. For example, is it common to leave out lights and utilize the illumination channal instead and then turn on AO, and thus not needing lights...? And is that really practical given that it greatly effects render time for every frame of an animation. Any insight would be greatly appreciated.

 

Here is an example of something I am working on using just the built in autolight

http://www.isaacp.com/videos/safe_objects_spin_h246.mov

Edited by ikep2008

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I don't know if there is one common practice, but I can throw a few things out that I see folks doing:

 

- Use only the luninance channel, however, use a ton of fresnel and/or falloff shaders to give the illusion of shading. In addition env channel for reflections. Then no lights at all.

 

- Build the lights into your scene as bright white (or whatever color) luminant materials and turn on GI.

 

- I made a light called "CS_KinoSquare" for easy mograph lighting (download in my sig). You can also use "CS_Daylight" and turn the skycolor slider to zero so it's white light. It does a bit of a skydome effect with rim and keylights built in.

 

- Only use luminant materials again, but texture map all the objects to have something interesting about them. It's how most AE motion graphics are done. Layers in AE are naturally luminant all the time unless you engage the lights, but people make them look interesting anyways with content, shading, masking, etc.

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Thanks Chris et al. for the really helpful info. Looks like there are a variety of useful approaches, which would ultimately contribute to ones style.

 

Here is an example of a lighting issue I am trying to resolve. See link:

Lighting issue

 

There are not lights in this seen. The wood background slopes is a floor that ramps up. The problem is the auto light only lights in relation to where the camera is pointing, so here the floor is too dark under the "Meeting" text and the wall is lit up. If I add a light for the floor than the nice autolighting becomes disabled. Any specific ideas to fixing this. Note this is only one frame of a sweeping camera animation.

 

Build the lights into your scene as bright white (or whatever color) luminant materials and turn on GI.

Chris,

So by the above point you mean use an object with high luminance in place of an actual light?

 

I will have to experiment with the CS tools. Interesting your point on AE. I never use lights in AE and I guess now that I am learning C4D I have carried over the habit.

Edited by ikep2008

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So by the above point you mean use an object with high luminance in place of an actual light?

 

I will have to experiment with the CS tools. Interesting your point on AE. I never use lights in AE and I guess now that I am learning C4D I have carried over the habit.

 

 

Yes, correct. With GI on it will see an object's luminance as a source of light. You can also use values higher than 100%.

 

Colin mentioned Monkey's RGB light thing. If you use CS_Flicker and change the 3 colors from the default "fire" colors to Red, Green, and Blue. It does that effect pretty well. You can turn off all the 'amp' sliders so the 3 lights are static. If the 'rig size' is at zero, then the lights are on top of each other and are now effectively a white light. But make the rig size bigger and the 3 colors start separating. It makes a nice color wash look *kind of* like the Chromatic aberration effect although not remotely accurate. Then if you want some interesting shifts, then re-engage the vibrations on the lights and those color washes shift (including the shadows if you turn them on).

 

I may also plug the GreyScaleGorilla tutorial in my sig. Nick shows how he uses the CS_AmbLight and CS_Arealight on his motion graphics.

Edited by C.Smith

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im just curious chris what you mean specifically about using the env channel for reflections?

 

it would be cool like the TP presets to somehow have a gallery of some shots and the materials used. I feel like env and diffusion are the channels i feel least confident with how to use them well

 

i know some of that are people's secret sauce, but it would also help raise the bar on what is being done in c4d

 

i do have cinversity, and am trying to get through of it to understand the little details on material, but the sassi tutorials are bloody long and the examples are less than inspiring

 

seems like in addition to "this does this" there are some useful best practices not always mentioned in those tutes like using fresnel in reflection or layered into luminance, Amb. Occ in luminance channel

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im just curious chris what you mean specifically about using the env channel for reflections?

 

it would be cool like the TP presets to somehow have a gallery of some shots and the materials used. I feel like env and diffusion are the channels i feel least confident with how to use them well

 

i know some of that are people's secret sauce, but it would also help raise the bar on what is being done in c4d

 

i do have cinversity, and am trying to get through of it to understand the little details on material, but the sassi tutorials are bloody long and the examples are less than inspiring

 

seems like in addition to "this does this" there are some useful best practices not always mentioned in those tutes like using fresnel in reflection or layered into luminance, Amb. Occ in luminance channel

 

As you probably know the env channel is a place to add texture maps or other shaders to get reflective properties as opposed to using the reflection channel which reflects only what is ACTUALLY in the scene with the object. In motion graphics where things are far less literal, then you can exploit the env channel to put in textures so that the object looks pretty without relying on what's around it to reflect.

 

Like a certain simian around these parts puts an HDRI map (upside down even) and other shaders like falloff in his env channel and it looks purty if you ask me.

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As you probably know the env channel is a place to add texture maps or other shaders to get reflective properties as opposed to using the reflection channel which reflects only what is ACTUALLY in the scene with the object. In motion graphics where things are far less literal, then you can exploit the env channel to put in textures so that the object looks pretty without relying on what's around it to reflect.

 

Like a certain simian around these parts puts an HDRI map (upside down even) and other shaders like falloff in his env channel and it looks purty if you ask me.

 

Also heard he puts a White to Black to White Gradient in 2D - V but that could be unsubstantiated hearsay.

 

Picture%201.png

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My secret sauce is totally making a few cool gradient ramps for the Env channel. You can get some super slick looking highlights without needing a full HDRI solution, and you can of course render it to a separate pass for tweaking later. Also a nice way to fake a fancy-pants car paint shader. I did a car spot with an 8 point gradient in the env channel and it came out ace.

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My secret sauce is totally making a few cool gradient ramps for the Env channel. You can get some super slick looking highlights without needing a full HDRI solution, and you can of course render it to a separate pass for tweaking later. Also a nice way to fake a fancy-pants car paint shader. I did a car spot with an 8 point gradient in the env channel and it came out ace.

 

Sounds, nice. Have any examples?

 

I've messed around with going to Bodypaint and enabling 32bit mode and painting with over-bright colors on a sphere to use as a SKY object map or as an env map. So it's technically HDR, but I made it myself. Works great for simulating softboxes and what not.

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Sounds, nice. Have any examples?

 

I've messed around with going to Bodypaint and enabling 32bit mode and painting with over-bright colors on a sphere to use as a SKY object map or as an env map. So it's technically HDR, but I made it myself. Works great for simulating softboxes and what not.

 

Chiggity check it out.

 

carpaint_example_01.jpg

So here's my crazy grad. This is just in the environment channel. I used a danel shader here, but it'll also work with a standard material.

 

carpaint_example_02.jpg

But since we have this crazy environment texture, the bottom of the car can look like it's lit from below even though it should be in shadow. So I stacked a layer material here with a cel shader used to dim it down to black based on lighting. There's also some tweaking to brightness/etc. here.

 

yaris.jpg

And here it is in action. It's a pretty fast render, too.

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some nice tricks in here for sure, hadn't really messed with the environment channel. definitely going to play with that...

 

Another simple option if you like using actual lights is to just use the exclude/include options in the scene tab on the lights & layers to restrict what objects the lights are hitting... that way you can light different parts to fit however you like, definitely depends on the look your going for though.

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My secret sauce is totally making a few cool gradient ramps for the Env channel. You can get some super slick looking highlights without needing a full HDRI solution, and you can of course render it to a separate pass for tweaking later. Also a nice way to fake a fancy-pants car paint shader. I did a car spot with an 8 point gradient in the env channel and it came out ace.

 

 

ditto that

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this is an awesome idea, never thought of it.

 

I've been loving the colored edge falloff gradients on the spotlights lately... light rainbow-ish fringing on them gives it a warm natural feel. You can get some pretty sweet results with 2 different lights, each with their own different colored gradients, aimed slightly apart... all those layers of color start blending and falling off in pretty nice ways. Combine a few of those with some really soft shadows and you can get nearly-ambient occlusion looking renders really fast.

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this is an awesome idea, never thought of it.

 

I've been loving the colored edge falloff gradients on the spotlights lately... light rainbow-ish fringing on them gives it a warm natural feel. You can get some pretty sweet results with 2 different lights, each with their own different colored gradients, aimed slightly apart... all those layers of color start blending and falling off in pretty nice ways. Combine a few of those with some really soft shadows and you can get nearly-ambient occlusion looking renders really fast.

 

ahh. nice one. Combine this with some Knoll Lens Flare and you are rocking.

 

Colin

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My secret sauce is totally making a few cool gradient ramps for the Env channel. You can get some super slick looking highlights without needing a full HDRI solution, and you can of course render it to a separate pass for tweaking later. Also a nice way to fake a fancy-pants car paint shader. I did a car spot with an 8 point gradient in the env channel and it came out ace.

 

Yeah I made a great chrome material this way, with a gradient in the enviro channel.

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