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Pakorn1
07-07-2009, 08:29 AM
Hi all,

I'm working on a medical project that uses a bit of normal mapping to show depth in between muscle striations. I want to be able to show off the space between the muscles as well as some specular value I've applied to the muscle to make it look realistic.

However, so far my lighting rig has been very simple; a white background with Radiosity set to "backdrop only," and all lights' Diffuse and Specular properties turned off. This is a great lighting setup to use while showing off models to clients; it makes a great "clay" effect that looks awesome on solid gray textured models, gives a good amount of depth, adds some nice soft shadows, and it seems to render pretty quick. However, when I use this lighting with Normal maps, I don't see any depth. I think its because the light is coming from all sides?

So here's my question - I need a nice lighting setup that will give me the depth of the "clay" render, but will still give me a nice normal map/specular effect. Anybody have any tips/tutorials I could use? Any help here would be greatly appreciated, since I'm not too familiar with any advanced lighting and rendering techniques in Lightwave apart from a standard three-point setup with Spotlights (which looks great in the normal maps, but there's no depth in the geometry - the model looks "flat".)

AdamAvenali
07-07-2009, 08:40 AM
i usually do a combination of background radiosity and a three light setup (key, fill and rim light). you are exactly right about the overall flatness from radiosity, that's why you need a light casting some direct shadow and spec, the same applies to bump maps.

here's a link for some video lighting tips: http://www.video101course.com/300light280.html

RebelHill
07-07-2009, 09:30 AM
u also wanna make sure that "use bumps" is enabled in the radiosity panel.

biliousfrog
07-07-2009, 09:31 AM
There isn't a simple, one-step solution which will cover everything. Start by turning off radiosity and try to get the lighting right first. Radiosity works best when adding to the existing lighting setup, even if it's just a single 'sun' light or three point rig. I can highly recommend DPont's additional lights for LW9 which has an excellent spot light and infinite light with soft shadows. Once the lighting is looking good try adding some GI to soften the shadows and add some 'zing'.

For a nice studio style setup, set the background to black or a dark gradient and use Luminous polygons to cast diffused light and add interesting reflections. Remove or reduce any specularity and use reflections on surfaces instead...You'll need GI for this to work effectively.

Experiment with backdrop images and radiosity to break up the lighting. HDR images work great but any image can be used to add subtle colour changes. Search the forums for free studio HDR images, they work very well for a fast, clean lighting setup without the flat lighting you get with a solid background colour.

Pakorn1
07-07-2009, 11:11 AM
Thanks guys for the responses!!

Adam and Rebel, thank you, that was exactly what I needed. I didn't really realize that you could combine the two, since my renders always looked oversaturated. But I turned the three-point lighting values down quite a bit and also made the background gray instead of white, and it seems to work pretty well.

Biliousfrog, thanks for the tips regarding HDR and advanced lighting; being "new" to LightWave, I haven't gotten into trying super-realistic images just yet. Where can I find DPont's lights? I assume it is a LW Plugin? Also, does it add a lot of time to the render? The project is on kind of a tight budget, and I'm trying to keep render time minimal for the animations we're creating (currently I'm at around 2m per frame, which is actually a little higher than I'd want it.)

biliousfrog
07-07-2009, 12:31 PM
http://pagesperso-orange.fr/dpont/plugins/lights/Additional_Lights.html

Be careful with using radiosity with animations unless you're quite comfortable with the radiosity settings. The lights don't have any more impact on render times than the Lightwave defaults but it's all relative to everything else in the scene and your hardware.

Except's guides should help you with getting the best from Lightwave's radiosity: http://www.except.nl/lightwave/RadiosityGuide96/

Pakorn1
07-07-2009, 02:39 PM
Cool, thanks again Bilious. I replaced my lights with default DP Infinity lights, and have something that's actually pretty decent (and renders in about a minute and a half, so if anything, DP made things a bit faster? Also I am using a FastSkin material which I think is adding a lot of time to the render.)

I'll have to run through the Except guide in my own time and see if I can get it looking even better - Thanks again all!!

monovich
07-07-2009, 04:29 PM
I throw in lights with "specular only" to pop additional detail in the bumps/normals.