There are terms coming up in Poser 8 discussions that don't really make sense to me as a non-techy person. Could someone give good plain language explanations of some of the new terms?

These Render settings:
Indirect Light Quality
Tone Mapping
Tone Mapping (Exponential)
Preview Hardware Shading

Also... how does Ambient Occlusion Work with Indirect Light?

Is "IL" a new light like IBL or is it a material thing like AO shaders.

If IL is in the materials... does it respond with certain characteristic differnces to Inifite Lights, Spot Lights, and Point Lights or lights with shadows as opposed to lights without shadows?

Do you need a full panaramic scene to provide the information for IL? For example, if you render a figure in an empty universe with the floor turnred off does IL have any effect?

I saw a post by BB saying that in an interior scene with IBL and IL the IBL works only through the openings in the walls such as windows while the IDL works inside the scene... does this mean that IL can fill the function that IBL filled before in "closed interior scenes"? Would I want want the "fourth wall" visible so the IL works properly?

Can the effect of IL be adjusted for intensity? I feel the sample renders I am seeing here in the forum are lit a little strongly as though filled in with a lot of reflectors... when IBL first came on the scene it was set a little too aggressively by most people and lots of renders showed up that were blown out and flattened by a lack of shading then over time people started turning IBL down to 15-30% or setting all the diffuse in the scene to 50% gray.

BB, if you read this... is there a way to explain to a lay person like me how your EnviroSphere is a light emitting prop if I understand that correctly. Does IL work on a similar principal?

To my lay person's imagination the set-up of Indirect Lighting might be something like all the contents in a scene are mapped onto the interior of a ball surrounding the scene and then the colors and values of this map are projected back onto the scene elements by the render... in the old P4 days I faked this with gradients or environment maps plugged into the Ambient node of my materials.

I don't have all your answers, particularly I don't have a good understanding of what Tone Mapping actually does - in principle, it tries to give you more color information in the output than you'd get without it.  Basically it helps you avoid the brightest parts of your image from blowing out to completely white, and the darkest parts from going completely black.

Preview Hardware Shading (actually available in Poser 7 also) - if your graphics card supports the features it requires - will give you more accurate preview when dealing with complex materials, particularly stuff like Blender nodes.  With it turned off, you won't see the result of any Blender nodes; with it turned on, you'll get a pretty accurate preview of what they look like in the final render.

According to Stefan Tewer (stewer, the guy who wrote the renderer) Light-based Ambient Occlusion (that is, when you turn on Ambient Occlusion on a light) is skipped when Indirect Lighting is turned on.  Material-based Ambient Occlusion (that is, when you have an Ambient Occlusion node configured for a given material) is still processed, but incurs a heavy computation hit when rendering with Indirect Lighting turned on.  In many cases, you may find you don't need to use AO when working with Indirect Lighting, as IL does similar things but in a smarter and more realistic way (ideally).

Indirect lighting is neither a new kind of light or a material, it's a render setting.  It is more commonly referred to as "Global Illumination" in other rendering apps.

You do not NEED a full panoramic scene to use Indirect Lighting, but imo for indoor scenes you really should have an enclosed environment.  If you have, for example, a floor without walls or ceiling, most of the light will go from whatever light sources in the scene, to the first surface it encounters, and bounce off of it - and then vanish into the empty universe surrounding it.  This really defeats the purpose of using Global Illumination techniques.  Outdoor lighting is a different matter, and in those cases you'd probably want some kind of sky dome (Bagginsbill's environment sphere for example) to be your main source of light, to get good results.

Yes IL can be adjusted for intensity (with Dimension3D's render interface script), although keep in mind that you're seeing early results from people with bad habits that stem from older versions of Poser, where you had to have a bunch of fill lights or IBL to avoid having parts of your image be completely black due to the unrealistic way lighting was handled.  This is just technique, and as people get more comfortable with the results that come out of the renderer with IL enabled, you can expect the over-lighting you're seeing to get better.  You can adjust it if you really want to, but imo it's probably better to adjust the lighting instead.

Bagginsbill's environment sphere prop emits light by plugging color into the Ambient_Color and value into Ambient_Value channels of the sphere's materials.  This works the same for any material anywhere in your scene, if it has Ambient color and value information, then it will emit light that Indirect Lighting will cast around the scene.  This is a standard feature of Global Illumination in other apps, and can give you some very interesting results that were pretty difficult to obtain in older versions, like the famous "bioluminescence" thread.  Now instead of having to set up Gather nodes everwhere you want a surface to be illuminated by a glowing material, you just make the material glow.

Wow, pjz99! I actually understood all that!!! Thank you :) It was kind of you to take the time.

Minor nitpick.

GI is a great term but it encompasses a broad category of techniques. For example, Wikipedia claims:

• Radiosity, ray tracing, beam tracing, cone tracing, path tracing, Metropolis light transport, ambient occlusion, photon mapping, and image based lighting are examples of algorithms used in global illumination.

Indirect Diiffuse Lighting (IDL, aka diffuse inter-reflection) is a specific form of GI. I'm glad that Poser calls it IDL, not GI. If we get MLT or other unbiased techniques, or Photon Mapping, that's a whole nother awesome kettle of fish. Those are GI, too, but we don't have them in Poser 8.

Some of us have occasionally been lazy and written IL but I prefer the acronym IDL. It reminds us that caustics, SSS, and even simply specular reflections are not involved in it.

Momodot, we didn't answer all your questions yet, but I really need to go to sleep. I'll come back. If I forget, poke me.

it's werner, not tewer, in case anybody asks.  particularly important when writing the cheques and bonuses.

Oops, I knew that (Stefan Werner).

The fact that caustics is not included can throw you - if you have a completely reflective material on a surface like a square mirror, and you shine a light on it, you would expect that the mirror would reflect a bright square of illumination somewhere.  It won't, that's caustics.  People tend to think of caustics as the "magnifying glass" effect thrown by refraction, but it also applies to reflection.

I found this on tone mapping on Wikipedia:
en.wikipedia.org/wiki/Tone_mapping

OK, well I already pretty much knew what it was through using other 3D software, but how does Poser 8 do it?

Excellent. Thank you, BB.

Quote -
Bagginsbill's environment sphere prop emits light by plugging color into the Ambient_Color and value into Ambient_Value channels of the sphere's materials.  This works the same for any material anywhere in your scene, if it has Ambient color and value information, then it will emit light that Indirect Lighting will cast around the scene.  This is a standard feature of Global Illumination in other apps, and can give you some very interesting results that were pretty difficult to obtain in older versions, like the famous "bioluminescence" thread.  Now instead of having to set up Gather nodes everwhere you want a surface to be illuminated by a glowing material, you just make the material glow.

But you do have to go through your materials and remove ambient color and value, and remove AO nodes. Fortunately, I think there is s python tool set at RDNA which allows you to do this without too much pain. (I haven't tried those details yet since I just got Poser 8).

Many aspects of old-school Poser materials will require attention, particularly Diffuse_Value.  Practically all Poser content has Diffuse_Value set to 1.0.  With Indirect Lighting, this is not good.  In the real world, light hits a material and some of it is absorbed - with Diffuse_Value at 1.0, all of the light bounces away at full brightness, and will not fall off in a realistic way (paraphrasing what Bagginsbill explained to me earlier).  Reducing it to a lower value, like 0.8, means that with each successive bounce, the bounced light's brightness will be reduced, gradually and realistically.  This means each and every material on each and every object needs to have Diffuse_Value reduced, except maybe for a totally reflective surface.

Is there a script that can change something like the Diffuse_Value in an entire scene? Sounds like a nightmare. All the old content will have shader problems when used with IDL? Be good to have a "switch" since you might want to proof a scene without IDL and then use IDL for the final. There is a free script at ShareCG that sets the Diffuse_Color of everything in a scene to 50% gray... would using that be an alternative do you think? Be cool if someone made some freebie scripts that would optimize stuff for IDL renders. I have always wanted a script that adds edge blenders to everything for that bit of edge contrast for when the light flattens a render... I know it isn't accurate optically but it is acurate perceptualy since the retina and optic nerves do a bit of "post-processing" before images get to the visual cortex... I think the Early Ren artists gave things that kind of "abstract" edge shading rather than rational light based shading but they were dealing with a kind of abstract "Divine Light" illumination of their scenes.

Point me to that script and I'm sure I can modify it to do Diffuse_Value to 0.8 instead.

This?
http://www.sharecg.com/v/23657/script/Set-diffuse-gray-script-,-for-light-set

http://cid-b233dcaeefa9709c.skydrive.live.com/self.aspx/Public/Poser%20Freebies/Diffuse%7C_Value%20Script/Diffuse%7C_Value%20Script.zip

Thank you pjz  :)

Quote - This?
http://www.sharecg.com/v/23657/script/Set-diffuse-gray-script-,-for-light-set

That script seems to change the diffuse by changing the color. It will work for most shaders, but not those which already use the diffuse color to modify the input from a texture map or a shader.

Testing the new script now............ Good news, it does exactly what we need. :D thanks pjz

Quote - > Quote - This?

http://www.sharecg.com/v/23657/script/Set-diffuse-gray-script-,-for-light-set

That script seems to change the diffuse by changing the color. It will work for most shaders, but not those which already use the diffuse color to modify the input from a texture map or a shader.

I think PJ was just asking for confirmation that this was the script that he was supposed to start from and modify to make the new one he posted after.

Thank you PJ!!!

Wow!  Thank you!!! And clear enough I can tweak the value if I want. Thank you very much :)

Yeah I'm sorry if I was too brief, I have an injured dog just now, I threw that together while waiting for the vet appointment (which I'm leaving for now).

alternate link:
http://sites.google.com/site/fleshforge2/Home/free-stuff/set-diffuse_value-to-0-8-script

Good luck at the vet's.