I've seen a few threads where people are struggling to light complex exteriors/interiors and I think it would be nice to share some tips/tricks to make the whole thing easier and faster. I'll start.

Here we have a basic scene with one 'Sun' light and IDL. There are no textures for faster rendering and so that the issues don't get hidden under nice texturing. It has almost all the artifacts you run into with IDL (in all  cases open the pic in a new window to see full size, where applicable)

And these are the render settings.

Yes they aren't particularly high or optimized but they render fast (about 30-40s) We could pump them up to get rid of some of these artifacts (but not all) or disable IC altogether and do a really long render... but is there a better way ? Keep reading to find out :P

The first thing that comes to mind here is, "hey maybe the problem is that we are rendering our scene in the middle of nowhere. If we had a proper environment, the lighting would be much better..." So, here is the same render but with an envsphere (from BB.) The lighting is now better although very blue. BTW that's another common problem that arises because most 360 pics like this have huge skies and that turns everything blue-ish. But this is fixable by editing the pic or finding different ones. A bigger problem is that while the artifacts are less, they haven't gone entirely. There are also some new artifacts in a few places like those bright splotches at the small bump in the floor.

What else can we try ? Read on...

Interesting!

Quote - What else can we try ? Read on...

I've read 'on' 147 times and it still says on... 

So what can we do to fix all this ? Well one interesting thing to note here is that direct light (the kind you get from traditional spot, point and infinite lights) is essentially artifact free. If you point one of these at a mesh and render you will mostly get a nice clean result. It's when light starts bouncing around that you run into problems. Is there any way we can use this to our advantage ? Well we can certainly try :)

Here is the original scene (without the envsphere) with a 'helper' light placed facing the opening in the scene. The light has low intensity (30%) a slight blue color and raytraced shadows with max blurriness. As can be seen most of the artifacts have vanished ! The reason for this is that in the original render, most of the light was bounced from IDL (which is artifact prone) but now most of the light is from direct lights (the Sun and the Helper)

And the same scene with the helper and the envsphere (with the saturation/value turned down a bit) :

Forgot to ask: will this be available as a .pdf for those of us who work from paper when we do tutorials?

Quote - Forgot to ask: will this be available as a .pdf for those of us who work from paper when we do tutorials?

https://addons.mozilla.org/en-US/firefox/addon/print-pages-to-pdf/

Yes, that was the plan :) I'll post more examples in the next few days (more complex, 'real world' ones) and try to answer any questions. After that i'll bundle it all into a PDF and make it available for download.

BB and I discussed all this some time ago.

 - raytrace bounces is too low, in your render settings rays are cut off after 5 bounces. Nature uses infinite bounces. Pump up the volume. Use the D3D Render Firefly script to discriminate between reflection bounces and IDL bounces.

 - the scene is not closed, but open at one side. This is a huge lighting leak. Increasing the bouncing will hardly help when you don't stop the leak. Just a far-away dome won't do, so build up the missing wall.

 - irradiance caching is too low, only 30% of the area is re-emitting light from calculations, the rest is guessed. Decent values for high end quality renders should be no less than 80, lower values are for testing purposes. Values over 90 are overkill and add more to the render time than to the quality. So does switching off the cashing completely.

 - IDL quality is too low. This parameter is to be used to limit the artifacts when you want decent results with relatively low irradiance caching settings. Having them both at a low value is asking for reduced quality results. It's in the manual.

 - and in addition: do not put direct lights which an (inverse) quadratic falloff too close to any surface, or you will face scattering artifacts (since the falloff formula will make the lighting levels too high close to the lights, and IDL makes the surfaces reflect that.)

 - plus: when the scene hosts a few small IDL light sources only you run the risk of splotchy shadows unless all rendering options (and render time!) are pumped up. Just do as photographers: use large softboxes instead. This is my general note: Poser is a virtual photo studio, so you have to light scenes as a photographer would do.

Hope I didn't spoil the fun of this thread too much. Sorry for that.

The missing wall is not a problem (leak) if you're modeling the lighting of a real outdoor seating area (think porch). In that case, the sky and environment will contribute far more than the missing wall would be contributing. The missing wall is a net addition when the env sphere is bright.

Re glowing couch back against wall - IDL reflection is wrong in Poser. Use D3D dialog to decrease IDL intensity to .65.

Wow guys, many thank to all, you are try to show to me (i'm a nerd with poser light) how to use light in my actual scene (http://www.renderosity.com/mod/forumpro/showthread.php?thread_id=2877138&page=1#message_4129030)

I'll follow you very hard.

since I have the scene with all the textures, if you advise me step by step how I can proceed with post render effects much more accurate and realistic.

Build it together step by step

First problem.
The type of image for the env sphere
which picture you recommend?
Possibly with a link to download

Second problem

env sphere setting

third problem

Sun light settings

Quote - - raytrace bounces is too low, in your render settings rays are cut off after 5 bounces. Nature uses infinite bounces. Pump up the volume. Use the D3D Render Firefly script to discriminate between reflection bounces and IDL bounces.

* - irradiance caching is too low, only 30% of the area is re-emitting light from calculations, the rest is guessed. Decent values for high end quality renders should be no less than 80, lower values are for testing purposes. Values over 90 are overkill and add more to the render time than to the quality. So does switching off the cashing completely.*

* - IDL quality is too low. This parameter is to be used to limit the artifacts when you want decent results with relatively low irradiance caching settings. Having them both at a low value is asking for reduced quality results. It's in the manual.*

 
If high render settings is the 'solution' you may as well use lux. The idea here is to see how far you can get with fast renders under ordinary settings. It's in the first post: "Yes they aren't particularly high or optimized but they render fast (about 30-40s) We could pump them up to get rid of some of these artifacts (but not all) or disable IC altogether and do a really long render... but is there a better way ?"

Quote - - and in addition: do not put direct lights which an (inverse) quadratic falloff too close to any surface, or you will face scattering artifacts (since the falloff formula will make the lighting levels too high close to the lights, and IDL makes the surfaces reflect that.)

'Scattering artifacts' are a direct result of people trying to push more light into dark scenes with super bright sources (500%, 700% etc) The problem is CG lighting doesn't always work like real world lighting, not in Poser anyway, so all you get is blown out areas near the light and dark areas everywhere else. There are better ways to do the same thing.

Quote - Hope I didn't spoil the fun of this thread too much. Sorry for that.

Not at all :)

Quote - Re glowing couch back against wall - IDL reflection is wrong in Poser. Use D3D dialog to decrease IDL intensity to .65.

I didn't know that. Could you elaborate on what the problem is ?

ref BB's note: closing the scene one way or another is essential to good IDL lighting. When the scene is meant to be a room with a wall left out in a sunny world, my suggestion is to bring back the wall (AND have the dome), perhaps an "invisible to camera" might be helpful for good shots. When the secen is meant to be an outside porch, don't do the wall as it's not there in real life either.

Actually, looking at an outside porch just didn't occur to me. That's not the scene, that's me :-)

For an outdoor IDL scene, all you need is a dome acting for cyan sky with enough clouds, and a white infinite direct light acting for sun, and supplying the specularity (as IDL will give diffuse light only). The best dome image is the one that is the best representation of the outdoor environment, it's that simple. For great skies, look into Richardfotos gallery. He's the best (IMHO).

About render settings: sometimes 5 sec for adjusted settings plus 30 min extra rendertime pay off against 2 hours elaborating on a shortcut. The max values are not the best, but just altering the settings might make the difference between mediocre and good enough. Then use small images to find out where it pays off to tweak on the large high quality results. Is my opinion.

Quote - .... Richardfotos gallery. He's the best (IMHO).

Please, give us the link, thanks.

just http://www.renderosity.com/mod/gallery/browse.php?username=richardphotos (sorry, fotos with ph, English is not my first language) and then pick the sky photos you like, and be sure to have his consent in doing so.

Recent ones:

http://www.renderosity.com/mod/gallery/index.php?image_id=2502528

http://www.renderosity.com/mod/gallery/index.php?image_id=2500735

and a zillion more

Ok, may you suggest me setting for BB's dome ?

Another question.

You suggested this thing:

Quote - use large softboxes instead

I tried to use this technique but the problem is that "large softboxes" are visible on every reflective surface and sometimes even in the eyes of the characters.

There is something that I do not know about "large softboxes" or is there a way to hide them?

Or may be there are "large softboxes" that emit light but are totally invisible on reflective surfaces?

Many thanks

tip 1: think as a photographer. You're outside, on a clear daylight, want to shoot the porch and you need more light allover the place. What kinds of extra light do you need, and where do you place them.

tip 2: create an array of low intensity spotlights, flaps open, soft raytraced high quality shadows. Sometimes I use 5 (1 in the middle, 4 in the corners parented to the middle one for easy handing), sometimes I need 9 (in a 3x3 setup).

little secret: direct lights do not turn up in reflections but in specularity only, and you can turn the specularity channel OFF for that light in the Material Room.

tip 3: in portrait photography, a softbox should be at least as large as the (part of the) model you want to shoot, and should have a distance to the model of about the diagonal size of the box = say 150% the height or width.

Quote - tip 2: create an array of low intensity spotlights, flaps open, soft raytraced high quality shadows. Sometimes I use 5 (1 in the middle, 4 in the corners parented to the middle one for easy handing), sometimes I need 9 (in a 3x3 setup).

Parameter light example ?

start and end corners ?

thanks

For the 5-light setup I start each with: white light, 20% intensity (as 5x 20% = 100%), corners 0-160 as in "flaps open", specularity OFF (Mat Room) when you don't want the reflections, shadows OFF if you just need the light or: raytraced shadows at blur radius 20 and shadow samples 200, and no ambient occlusion when rendering in IDL.

Then I continue playing with falloff-types, falloff distances and intensity levels as real photographers are playing with their light knobs and meters.

Check my cameray/light/render tutorial starting at http://www.book.artbeeweb.nl/?p=3065

have fun.

the trouble here is over the

couchs

I played with all the possible combinations, but the problem does not disappear.

that's why I asked you and to BB the settings for BB's dome and sun light.

I think the problem comes from external light

this is the render

I have made a test with M4, the same problem is over the M4 skin, but this is a future step.

Quote - The missing wall is not a problem (leak) if you're modeling the lighting of a real outdoor seating area (think porch). In that case, the sky and environment will contribute far more than the missing wall would be contributing. The missing wall is a net addition when the env sphere is bright.

Re glowing couch back against wall - IDL reflection is wrong in Poser. Use D3D dialog to decrease IDL intensity to .65.

^^ This.

Smith Micro developers don't even use their own product or else they would of set the default IDL lower.  Hopefully poser ends up in the hands of a competent company in the future.

Quote - Thanks aRtBee

the trouble here is over the

couchs

 

I played with all the possible combinations, but the problem does not disappear.

that's why I asked you and to BB the settings for BB's dome and sun light.

I think the problem comes from external light

this is the render

I have made a test with M4, the same problem is over the M4 skin, but this is a future step.

1. Use one directional light with IDL at 6.

2. Add BB's EnvSphere.

3. Try another couch to see if the same problem exists, or any other object where two planes meet at 90 degrees.

4. Simplify the textures on the couch as much as possible.

5. Set the irradiance cach for IDL higher (70 or higher) and the irradiance caching for raytracing to 100.

The point is, there is no setting of anything that reproduces your issue, the deep shadow stroke at the in-side of the block.

So the question is, if you reduce the scene to 3 walls, 1 roof, 1 ground plane, 1 object, 1 dome and 1 light, and no textures, is it still there? If so, tell us your settings or make the scene available. If not, then start adding elements till it re-occurs.

Manu thanks asap i'll do this test.

Outside porch Three are a Lot offerte things,  i'll delete every material And do renders

okay. also please do some tests with decreased and increased setting for bounces. Then you'll see that this setting does have an enormous effet on the lighting levels. Its not  a matter of just quality vs render time, it's a really different image.

I will be away from your pc where I have Poser until Friday morning, meanwhile#### aRtBee  

, please, if you can give me the specifics of the room materials for objects that you used in your test

many thanks

all stuff default untextured. Diffuse white, 1 Specular white,1 and anything else black or 0 or nothing. I included the file.

Mano thanks

You can see 2 outside porch rendering so you can understand the entire scene.

I have used your materials, your light settings and dome settings.

But seems to me that the trouble on couch is still there.

So i don't think it's a material problem but general lighting problem.

hi xpdev

this is just one of those battles I like to win (from Poser, not from you). nice scene, by the way. yeah, I'm sure it's not in the materials as such, but materials do get in the way of interpreting the results, so "we can see clearly now".

It's something in the scene, in the lighting or in the interaction between them. Sometimes an object, in sight of at our back, is standing in the way somehow and generates a somewhat unexpected shadowing. That's wy I also suggested to make everything invisible, except for just 1 ground 1 roof 3 porch walls and 1 couch in the front. That's what I had in my test scene, and the extra shadow line did not show up.

When all material issues eliminated, and all object interferences are eliminated, and the issue is still there, then we're sure that it's the lighting interacting with the extremely simple porch setup. Than plan A. If the issue seems to be disappeared, then groups of objects can be made visible again until the issue re-appears, and in that way you can find the culprit.

plan A: try to find out to what extend the issue is a result of your render settings. First, increase the bounces (till max). Than increase IDL quality (till 80) then caching (till 80). All in steps, or just the max setting first to see if the issue is still there.

I'm building the scene.

But consider that what you see outside the porch is all in one props

This is the rendering result

The problem is still there.

no couch, but 2 boxes one over the other...

same problem...

that's why i think the problem is the ligthing

ok... waiting for you

It is why my Soft Studio Lighting sample scene does not only use glowing props for light, but also some traditional lights.

I posted this image to SM (along with the scene) in a bug report in 2009.

It's no longer as bad as this, but you can't make it go away.

In this scene by xpdev, it is lit correctly. All of the couch light is bounced or from the env sphere which is mostly occluded by the enclosure. There will be artifacts, unless you compromise your lighting and add a point light inside the enclosure, or other similar hack.

Notice in addition to a reduction of the corner artifacts, the reflection level that caused amplification has been reduced.

OK, BB

so what you suggest to fix my problem in the scene over your post ?

I'm not able to find the right way to have good lights under the porch and solve issue

what you mean with " or other similar hack."

i'm not able to find one good working

I thought I was clear.

"but you can't make it go away."

There is no solution. You cannot make what you want with Poser. You must compromise your lighting setup by adding an unacceptable, additional light.

This will change how it looks. The look you want cannot be created in Poser.

My suggestion: You should look into using Reality.

I supposed that there was no way out ...

Thanks BB and also to all the others.

I've found the following, after toggling about all lighting aspects and IDL properties of things.

The issue of a deep shadowed stripe over the couch (cube) that sticks somewhat out of the porch, is caused by the interference of the direct steep incidenting sunlight & shadow at one hand, with the indirect light - mainly from the sun also - bouncing from the ground onto the ceiling downwards onto the couch.

The first: direct sunlight, creates a bright portion on the "frontside" of the couch as far as the couch is in the light, then the brightness drops rather quickly due to the shadow from the ceiling/roof. Orange line in the graph for intensity.

The second is indirect light bouncing especially from the ground towards the ceiling. This turns the ceiling into a light source, with the largest intensity at the frontside, dropping towards the backside of the porch. But also dropping drastically above the couch itself, as the ceiling stops just there.
So when moving from the outside inwards, this portion of the lighting first rises as we get more ceiling above us, and then reduces slowly as things get slightly darker towards the back of the porch. Blue line in the graph for intensity.

Combining these two effects creates a high intensity level first, then a brighness drop as the direct sun-shadow kicks in, then an increase from the IDL light from the ceiling, and a slow drop as things get darker towards the end. Green line in the graph.
In other words: from some point the brighness from the ceiling (IDL) increases faster than the shadow from the sun (direct) decreases.

In nature, this issue does not happen because real IDL is not only caused by re-emission from objects but by scattering in the atmosphere itself too. And because bounces are infinite, and quality is 100%. So, in Poser you can

 - soften the direct shadows, set shadow intensity somewhat below 100%. This will not only reduce the shadow on the couch but will also reduces the darkness withng the porch.

 - increase shadow softness by increasing blur radius (you might have to go as high as 50) and shadow samples (take 10x blur radius), for the infinite sun light

 - increase bounces (render settings), which will increase the IDL level within the porch. Then the iDL will just overwhelm the shadows, makes the artefact less visible.

 - reduce IDL intensity (script > d3d > render firefly) to say 0.65. This will reduce IDL level within the porch.

The splotches as pointed out by BB are especially appearant in test scenes with strong color contrasts, and at low render settings. In rich textured scenes with high render settings, and some direct lights added in as well, Poser can do a nice job, and the rest can be fixed in post. Poser is nice for it's price, but not perfect for cheap.

I'm not saying Poser is so bad it's useless. I'm saying that what xpdev is trying to do (small lighting aperture, intense sun, narrow arc hot spot, deep shade, white couch with right angle facing away from dominant light arc) will not work. There will be artifacts, no matter how you set the render settings. I have tried everything for years.

An interesting read with good info! Keep it up peps.