#59: SHADOWS & LIGHT (Vue)
#58: ADVANCED DIRT MAPPING (Vue)
#57: SSS IN VUE 9, AND THE "SPECKLE" PROBLEM
#56: THE DEVIL IS IN THE DETAIL OF ART
#55: FIXING POSER CLOTHING
#54: MAKING "FOREST WAR - GOBLIN SHAMAN"
#53: MAKING A STUDIO RENDER FOR VUE
(and other apps)
#49: NEBULA MKIII (Vue)
#48: RENDER SETTINGS FOR VUE (Vue)
#47: POSTWORK - MAKING A RENDER INTENSE (Any)
#46: MAKING RIVERS THAT FOLLOW TERRAIN HEIGHTS (Vue or Bryce)

AREA LIGHTING FOR VUE

I made an extensive part of my previous tutorial on lighting in Vue, about area lights. (note this tutorial also applies to panel lights, too, in part)
But it's worth going into it in a specific tutorial, as I feel that area lights are over looked but provide wonderful quality for indoor and some other renders :)
I'll recap my previous tutorial, plus more info.

AREA LIGHTS (OBJECTS AS LIGHTS)

  A nice ability in Vue (for some versions), is to convert an object to an actual light source. You can do it on any Vue solid object, even a terrain, or an imported mesh.
The object will emit light, now, what's special is that in real life, light doesn't come from infinitely small points (apart from a black hole, lol). Our eyes notice this, real lights come from the radiating surfaces of objects, some quite large, such as burning buildings, or small like a candle flame. It has a serious impact on how shadows and lighting are formed.

  Area lights are nice because they throw a soft, dispersed light, with shadows showing the light source is more than a mere point in space, which never happens in real life.
Note the two pics below, the first shows a area light made from a cylinder, beside a point light, the second shows a figure illuminated by a large sphere (just off camera) turned into an area light.

  One of the tricks I've found with this technique, is to make a "magical" liquid or weapon glow (such as a magic potion). I duplicate the original liquid object, in the bottle, convert that to an area light and then make it so the lighted version doesn't show on the render, only it's light...gives a nice look ;) Sometimes you may need to re-size the area light object larger or smaller, and maybe add a glow to the original object's material, to get best "magical looking" results (see below).

You can hide form the render a duplicated object made into an area light, so only the original normal object will show, thus you get the best of both worlds: an original that's lit and maybe glowing because of the hidden area light object.
This is often necessary because an area light object loses material detail due to the brightness of it.
To hide an area light, at the moment, 12-03-2009, it depends on which version of Vue you have:

  • For Vue 6, just select "Hide object from Render" on the object panel, to hide the area light.
  • For Vue 7, make a new layer, make that layer hidden, then render and set the render options to render "Only visible layers", thus the hidden layer, with the area light, won't show, only it's light will.
    Rutra on Renderosity discovered this work around! :)
  • For Vue7, another way is to hit F6, to bring up scene material summary. Select the area light material. Select "only shadows", now the object is hidden but still shines light!
    This tip is from John Canver at E-On :)


  Note that sometimes (with Vue6 but not Vue7), a lens flare is applied as default when you convert an item into an area light, this is generally not what you want with such lights! Check for that.
Also, since they are, by their very nature, a "soft" light, area lights' shadows tend to be very noisy, requiring more rendering time to get rid of the "grain", or post work to blur it (more on this below)

  Vue 6 and 7 also has "Light Panels" in the choices of lights you can pick. "Light Panels" are flat planes that act as lights, basically an alpha plane converted to an area light. Very nice for some scenes, but again...tend to be noisy, so, long render times ;)
The disadvantage light panels have, is they don't have a curved or varied surface shape, which is what lets area lights made from objects have such lovely detailing the eye subconsciously notices. However, they are perfect for lighting built into walls etc etc.

Comparing the difference between an area and a quadratic point light.
You can see the area light produces a widespread, soft light,
not a locally intense light compared to the quadratic point light.

An area alight ceated from a human-sized sphere, illuminates this character. You can see how realistic the light is.
This shows how you can use the material summary editor (F6 key) to make an area light object invisble but still shed light.

 
When an object is converted to an area light, it's material is applied as a light gel, this may or may not be a good thing for you. If it's bad, just apply the basic Flat White default Vue material to it as a gel instead.
AREA LIGHTING DEMONSTRATION
Man on the left, I duplicated his sword blade. The original blade I added glow and luminosity too. The duplicate I converted to an area light, and turned on "Hide from render" so it wouldn't show. I don't know where the odd orange glow came from, maybe a bug, lol! Also made magic potion glow by the same trick ;)
Below, a slight glow, applied to the "gel" material of the area light, gives a great look like a flourescent tube etc.

AREA LIGHT TIP!


In Vue 7 I discovered the area lights were too grainy, while using better render quality helps, it doesn't solve the problem very well. There is however an easy way to fix it, it does increase render times, but not as badly as using very high custom render settings.

Edit the area light object, now, edit the "SOFTNESS QUALITY", put the quality slider to 100%, and push the maximum traced shadows sliders from150 to 400, or more ( try adjusting in steps of 50, test rendering the scene with just flat white material applied to everything for quick render times, I find 400 is good quality).
The default is only 4/16 rays which is far too few, pushing it way up gives wonderful soft shadows with no grain!
I find minimum rays 8, maximum 400 is good. For best results, 100% quality is needed!

However, in scenes where there's a lot of broken, irregular features, say, plants around the area, you may not notice the grain so much, so lower settings maybe quite fine and thus, save you render time. Indoors in a fine modern home with lots of flat, simple, clean surfaces, you would notice it more. So it's a question of trial and error.

INITIAL TEST WITH AREA LIGHT OBJECT (CYLINDER) WITH DEFAULT SETTINGS OF MIN. 4
AND MAXIMUM 16 RAYS
As you can see, extremely nasty grainy shadows.
area light test
TEST WITH THE AREA LIGHT EDITED, CUSTOM SOFTNESS BOOSTED WAY UP
area light test 2 high custom softness
TEST RENDERS GOING UP IN STEPS OF +50 TRACED SHADOW RAYS
Note, at 400/400 rays, it takes about 14 times longer to render than the default of 4/16 rays (approx 14 minutes versus 1 minute)
At 4/400 rays, just increasing the Max # of rays from the default, it took the same time as 400/400 rays, fyi, on this scene, because it's pretty simple. You don't want to use 400/400 though as letting it use a lower minimu setting of say 8/400 will help your render times a LOT on complex scenes! If the renderer only needs ot use 8 rays, it's good, rather than forcing it to use 400 when such maybe a waste of time, hence minimum 8 and maximum 400 allows the render the to stop wasitng time where necessary, but force high quality where possible.

Here, I put a simple Vue sphere in, make it an area light. I leave it at default quality for it's light. So, you can see the nasty grainy shadows.

Now, I hide the sphere as explained above, so it won't show in the render, and add a grass ecosystem.
The grass hides the grainy shadows! you can of course use higher settings of shadow, which will improve the look, but it shows that having a flat ground object or clean, flat surrounding objects will show the graininess worse than rough terrains and plants.

Up to you to chose the level of quality vs render time for the scene.


Now, to show some practical application and comparisons of this :)

Here, I load in a camp fire. I add in a point light above the fire. Not a bad look, but it's actually not very realistic. Camp fires have complex light and shadow coming from a very large area, not an infinitesimal point.

Next, I alter the material of some parts of the camp fire, and give them "Illumination". since I'm rendering in a Radiosity setting, the illuminatiion literally lights up the scene! Interesting, but not strong enough.

Please take not of this trick for other renders: with illumination on, in materials, radiosity renders will actually get lit up by them!

Increasing the illumination of the material, by the way, just overwhelms the object material and it becomes washedo ut and unrealistic, so you can't use illuminated material itself ot light this scene, but it can work very nice for some things, or to add light from objects such as LEDs, floor lights etc.

This time, I add in a sphere and convert it to an area light. Nicer, I think. Note some of the specularity on the armour is actually due to it showing the colour of the sphere object.

Next, I delete the sphere, and make the fire logs into area lights! Very interesting lighting, eh? :)

But you don't get logs glowing like that in real life, hehe!

I increase the quality of the log's shadow to show, but it renders much slower.
FInally, this time, what I do, is duplicate the original logs, make the copies into area lights, and hide them from the render as explained above. The quality of shadows and render is very high, took 44 minutes to render this, but, IMHO, it's very damn good. This is more what a real camp fire looks like!
I hope you find this of use! :)
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All original art, writing on this site, copyright of Steven James, "Silverblade the Enchanter" ©2012