Okay, after my learning experience about Poser's handling of lights I'm trying to understand better how they work and I already have a scene I can't figure out how to fix. I have a ruined temple - looks okay, shadows are what you would expect. I put a dead guy on the floor of the temple (he's based on the Freak, if that matters for any reason - I don't know what's important info and what isn't yet) and render and the temple casts shadows, the dead guy does not. He even looks like he's lit by different lighting altogether - very even and daylight colored, while the scene's lighting is blue moonlight and rather contrasty. For simplicity's sake I have turned all the lights off but one and I still get the evenly lit body. He looks like he was pasted in via Photoshop from another picture entirely. For sure, it looks wrong, wrong, wrong. :-) All of the lights are set to "cast shadow" but what is it that is preventing Mr. Moribund from casting one? I know I've seen something about this somewhere but at this point I feel totally overwhelmed by the flood of information and I have no idea where it was. Is this related to those "shadow cams" that I don't understand at all? Is it something directly tied to the dead figure? I have the render settings in Firefly set up fairly high so as to include raytraced information. Help, please!

Edit: Okay, I figured out at least a part of it; I didn't have "Ray Trace shadows" ticked in the light's Properties box. That helped some. But he's still evenly lit while the temple is not and he's still lit by daylight instead of the blue light I have set the one light to produce.

It might be that his skin material has either Ambient or Translucency set to something other than 0. These will give the impression of self-lit objects, and while it works okay in sunlight to give a more glowing appearance to skin, it really doesn't work at all in dimly lit scenes.

You found one problem. There are two kinds of shadow algorithms in Poser - depth-mapped shadows (DMS) and ray-traced shadows (RTS).

DMS uses a "shadow camera". This is a camera that is positioned where the light source is (or its direction at least). Before rendering the image, Poser renders it using the shadow camera into a shadow map. This shadow map is not a visual map, but rather a depth map, where each pixel value is set to the distance to the first object in the scene from the point of view of the shadow camera. Then as the scene is rendered, each spot is projected through the depth map to see how far the light reaches in that direction. If the object is further than the depth-mapped value for that direction, it is in shadow, otherwise it is lit by that light.

The amount of detail that can be held in the depth map depends on how much scene area it covers and its size. The default size is only 256, and while that's OK for a single figure, it is not at all OK for a building containing a single figure. So the building will appear to cast shadows, but the figure (or anything else relatively small) will not. In such cases, the lights "Map Size" should be increased. But with a large enough building, it still won't be very good. DMS is old technology and you should not use it unless you're really pressed for speed, such as if rendering an animation.

RTS is the new way to do shadows. It doesn't involve a depth-map. Instead, every time shadow data is needed, a new ray is cast towards the light, and Poser examines what gets in the way, if anything. RTS are much more accurate. However, they can be very slow when encountering something with transparency, especially partial transparency, since that requires that a new ray is launched and the data found by the first ray is combined with data from the second ray. If there are several layers of transparency (as is the case with trans-mapped hair) this can really be slow.

There are four kinds of Poser people.

1) Impatient and don't care about quality. These people insist on using DMS for speed and we make fun of them.
2) Impatient but want better quality. These people use RTS but they disable "visible in raytracing" on the hair, so it doesn't slow things down. Then they add hair shadows in postwork, or they just don't bother and we make fun of them.
3) Patient and demanding high quality. These people use RTS and make everything have shadows, no matter that it takes 40 minutes to render.

1. Animators. These people don't know what to use and we pity them.

As to why he doesn't look lit right, you'll have to show me a render, and your light settings, as well as the material settings on the figure.

Also:

I implied it above, but did not make clear. When using RTS, anything that has "visible in raytracing" turned off will not cast a shadow. So check that on the figure.

Thanks once again for the help. This is incredibly confusing! I do have the "visible in raytracing" turned on for the body. I'm attaching a closeup of him rendered after I figured out about that option; you can see that there are shadows, although with just one point source I think they should be a lot more emphatic; these are not deep shadows at all. And also, the light source is blue - you can see the temple seems bluish, but the guy does not. I also note that his shadows are not actually black like those of the temple - he seems to have a different gamma, effectively. I don't know how to copy the light settings down other than typing them manually; I'm a terrible typist so that's probably not going to happen if there are very many of them. :D

If you do a screen capture of your settings, save it as a jpeg and attach it to your post by clicking Browse... of the Attach a File: just below the Reply window.  Navigate to your jpeg and afterwards post your reply.

Quote -
  ...There are four kinds of Poser people.

1) Impatient and don't care about quality. These people insist on using DMS for speed and we make fun of them.
2) Impatient but want better quality. These people use RTS but they disable "visible in raytracing" on the hair, so it doesn't slow things down. Then they add hair shadows in postwork, or they just don't bother and we make fun of them.
3) Patient and demanding high quality. These people use RTS and make everything have shadows, no matter that it takes 40 minutes to render.
  4) Animators. These people don't know what to use and we pity them...

:lol:

I nominate this for post of the week.

Well, I found at least part of the problem by subbing in another body texture - I put plain old M4 Std-Res in there and a lot of the "glow-in-the-dark" quality went away. I still have the problem that the deepest shadows on his body are not as deep as other shadows in the image, though. And, of course, I didn't want M4 in this image. But that's a different story. 

Benboom,

There is a llght parameter that controls the strength of a shadow. It is called "Shadow". If it is not set to 1, the shadow is weaker than it should be.

If it that isn't it, I have on rare occasion found Poser confused about a light, and it was producing weak shadows even when it is the only light, as if the Shadow value was less than 1. In such cases I delete all lights and add one new light and test render. This usually fixes it.

What version of Poser are you using? Which service release? (menu Help/About will tell you product name (like Poser 8) and version number is at the button, something like 8.0.2.10435).

In the render above, I really need to know everything about each light, and also the materials.

Don't type - screen grab. If using a full screen capture, crop to just the light parameters and save as JPEG and attach to your post. Also show light properties.

By the way, in the last render, the side of the temple opening above his head is black not just because it is in shadow, but also because the side of the stone is not facing the light. When a surface faces away from the light, the light arrives at a very shallow angle and is weak. This is how things work in real life, assuming there is no light bouncing around from nearby objects.

However, a real temple would have secondary light bounced around from other surfaces, and that surface would not be near black at all. How to deal with this depends on whether you have Poser 8 or not. With Poser 8, you'd enable IDL and realism would jump up a lot. With other versions of Poser, you need to set up an IBL, and you must do it properly.

Since I don't know your version of Poser, and I don't know what lights you have there and what are the parameter and properties, I can only keep telling you tons of general stuff which will make your head explode. I could write 100 pages on lighting for you right now, because all the knowledge is present and organized in my head. I've experimented with Poser lighting and shaders for over 6000 hours and I know more than anybody except Stefan Werner who works for SM and maintains and improves the Firefly renderer. But you're not ready to receive all that. So if you want to solve this, you must show me everything, instead of me telling you everything that could be wrong.

Another thing you could do ...

It's not OK to share copies of a scene with copyrighted content in it. However, if you remove the figure and props and just have lights, cameras, ground plane, etc. then it is OK to distribute that scene file.

So - here's an option instead of screen shots.

Open that scene. Delete all figures and props. (Except you can keep any Poser primitives  like squares, boxes, spheres - they are allowed to be re-distributed.)

Save it as a new file.

Then rename it by adding .txt extension, and attach it to a posting in this thread, using the Attach a File: thingy under the Reply box. (You need to fool the forum into thinking its just a text file - otherwise it will not let you attach it. That's why you must change the file name to end with .txt. So if you save it as MyScene.pz3.txt it can be attached. Then I'll remove the .txt when I download it.)

If you do that then I can see everything - all parameters, all render settings.

Oh, this is interesting. I subbed in another model "Tanya" and HER shadows render correctly - the dark areas are dark as I would expect them to be. Only problem is, this is a girl. She's African American, too, and maybe the darker skin tone is really what is responsible for this effect...I have no idea. All I know is that the lighting in the scene looks right with her in it and it looks lousy with the Freak or M4 in it. Obviously, this is going to be along process.

Bagginsbill, thanks for all your help. I have to leave the computer for most of the day now so I can't experiment too much. However, I can say this - so far, the shadow value of the light hasn't helped the density issue - I found that one and tried various settings and never saw a change. I am using Poser * so I will have to look into IDL, something else I know nothing about. I am saving you comments in my scrapbook, and I hope that portions of them will mean more to me as I learn more. I'd really like to figure out how to use my original model instead of having to replace him with a girl! :-) I am using Poser 8.0.2.10911. Off for now --- 

Quote - 1) Impatient and don't care about quality. These people insist on using DMS for speed and we make fun of them.
2) Impatient but want better quality. These people use RTS but they disable "visible in raytracing" on the hair, so it doesn't slow things down. Then they add hair shadows in postwork, or they just don't bother and we make fun of them.
3) Patient and demanding high quality. These people use RTS and make everything have shadows, no matter that it takes 40 minutes to render.

1. Animators. These people don't know what to use and we pity them.

I'm number two. If it only took 40 minutes to render hair with 'visible in raytracing' ticked, I'd leave it on. If it only took 1hr 40 mins, I'd leave it ticked. In my case, the difference is multiple hours. I have a fairly OLD PC...

Quote - It might be that his skin material has either Ambient or Translucency set to something other than 0. These will give the impression of self-lit objects, and while it works okay in sunlight to give a more glowing appearance to skin, it really doesn't work at all in dimly lit scenes.

I got a few minutes to play with this just now, and John, you nailed it! I knew about the Ambient setting and had checked that (it was fine) but I overlooked the Translucency setting in your post. Re-reading the thread just now I thought to go back and look and sure enough - the developer had set all of the skin translucencies to .4 - this is the Freak but I was using the "Hairy Freak" texture from Jepe to get sort of a Jason & The Argonauts - looking hero. I had never tried it out in a low-lit scene like this one and he practically glows in the dark! I set them all to zero and the problem vanished.

Thanks to all of you, and now I have more info for my scrapbook, which is growing apace. :D

See, I told you the shader decides the color, not the light and shadows. In this case, the shader was set up to produce irrational colors, and no matter what you do with lights in that case, you get nutty stuff.

Really, there is absolutely nothing wrong with Poser's lights. It is the terrible, mindless abuse of shaders that causes the problems. There is a very limited purpose to the translucency parameter and it has been horribly abused for years.

The big lesson here is to examine all third party vendor shaders for inconsistencies and errors.  It is bad enough you waste time trying to figure out what you initially did wrong.

Quote - The big lesson here is to examine all third party vendor shaders for inconsistencies and errors.

Definitely.

There isn't a vendor that I trust completely enough that I can load in one of their products and press "Render" and know precisely what I'll be getting as output.

Glad you sorted it out, Benboom. Just make sure you check every texture you get. You'd be surprised just how many do the Translucency/Ambient thing. (And a whole load of other errors that I could mention.)

This is a great thread. Thanks BB and others for clearing up some lighting questions I needed to ask too.

 It's always a "Buyer Beware" world out there. One of the P7 artifact sets for instance is "The Apartment" that drove me absolutely MAD for days. The lights were perfect and NOTHING cast ANY shadows, DM or RT ticked!  I thought I had lost it. I restarted and restarted my machine and STILL, NO SHADOWS!

I went through ALL the materials for any weirdness. I went through all the render settings. STILL NO SHADOWS!

Finally I found out what was going on. ALL of the props in the "The Apartment" file had SHADOWS TURNED OFF!!  WTF?:cursing: My god.  SMITH-MICRO did this! That is where I got it from.

It just goes to show to NOT trust items you get for your inventory. Checking everything is a real pain, but there is no real way around it.

It's like Scotty said,"The more they overhaul the plumbing, the easier it is to stop up the toliet!"

Quote - Really, there is absolutely nothing wrong with Poser's lights. It is the terrible, mindless abuse of shaders that causes the problems. There is a very limited purpose to the translucency parameter and it has been horribly abused for years.

This makes a very strong case for a thorough study of / manual for / understanding of shaders before going into the material room and an equally strong case against just mucking around stringing nodes together until the desired effect is ostensibly achieved. That "mucking around" is the prevalent approach, and this is why we get such odd effects once we apply our own lights or try to get rid of nostril glow or whatever.

I have been pondering what the best approach would be to get the Poser Content Developer to embrace this concept and clamour for a definitive work to teach these concepts, but then, no Nodes For Dummies hue-and-cry appears to be forthcoming. As long as the concept of "rubbish shader" is not even considered by developers as something significant enough to avoid, we will continue to see this sort of issue arise.

Mind you: I'm not purer than the driven snow in that regard. I've unwittingly released some rubbish into the material-room wild myself. But, at least I'm aware that I have.

Some people learn by doing. If you know what looks right, you can get usable results from the material room through experimentation.  Unfortunately, some people are the visual equivalent of the tone-deaf and there really is no help for that. 

 It might be a good idea for developers to do a "WITH shader nodes" and "WITHOUT shader nodes" material collection for the material room.  A doctor-like "Hippocratic oath like" attitude of doing no harm is always better.  Having a "lights on/lights off" collection would be easy to do and easiest for all concerned with the least amount of problems,IMO.

Well, I think the stores should require that merchants submitting items pass a simple test. If they did this it would solve a lot.

With a single infinite light on the right side, and a uniform white IBL at 3%, render the item. If any part glows it gets rejected.

 Wouldn't it be simpler to look for glows with a render with NO lights?

Wouldn't help with shadows,though.:laugh:

Quote - There isn't a vendor that I trust completely enough that I can load in one of their products and press "Render" and know precisely what I'll be getting as output.

Stonemason, Aery Soul, Rebelmommy, Subgraphick

I agree, it's a short list, but there are some vendor's who I've grown to trust over time.

Quote -  Wouldn't it be simpler to look for glows with a render with NO lights?

Wouldn't help with shadows,though.:laugh:

Abuse of translucence will not show glowing if there are no lights.

Abuse of fastscatter will not show glowing if there are no lights.

Misconfiguration of fastscatter when IBL is present will not be revealed unless IBL is present.

There are a dozen more.

Quote - > Quote - There isn't a vendor that I trust completely enough that I can load in one of their products and press "Render" and know precisely what I'll be getting as output.

Stonemason, Aery Soul, Rebelmommy, Subgraphick

I agree, it's a short list, but there are some vendor's who I've grown to trust over time.

Those *are good vendors. However, they have done some bad things. If you plan to use Global Illlumination, you must go through every material and check for Diffuse_Value = 1 - that is too high.

Quote - > Quote - > Quote - There isn't a vendor that I trust completely enough that I can load in one of their products and press "Render" and know precisely what I'll be getting as output.

Stonemason, Aery Soul, Rebelmommy, Subgraphick

I agree, it's a short list, but there are some vendor's who I've grown to trust over time.

Those *are good vendors. However, they have done some bad things. If you plan to use Global Illlumination, you must go through every material and check for Diffuse_Value = 1 - that is too high.

That would make the list incredibly short. Painfully so.

Problem is: testers themselves need to read the forums. I have it on good authority many of them don't. So none of this sort of thing is a priority. If paths work and files are all present, they're generally happy. I think.

 Pre-Poser 8 is what people know. Diffuse material=1 is the standard, as far as I have seen. In Poser 7 why would this be bad? It doesn't support Global Illumination. It may be months, if ever before I can afford a computer that will run P8.

Even if you don't use GI, when Diffuse_Value = 1, materials over-react to light, and the specular is not in the correct proportion to the diffuse. In some way, the over-reaction was actually desirable to many naive users, since they ignore or know nothing about gamma correction.

Many such users felt things looked better with Diffuse_Value = 1. Well under those conditions, where GC is being ignored, DV > 1 is even better. In fact, if you're going to use DV for compensating for lack of linear response instead of doing GC, then 1 is frequently the wrong value. The correct compensating value will depend on how much IBL you have, how much direct light, and what color the item is.

Or - with DV=.8, and GC and IBL (as in Poser Pro 2010) everything is near perfect all the time.

The trouble is - if a naive user fires up Poser Pro or Poser Pro 2010, they often complain things look flat and blown out and they reject GC and often reject IBL.

That's because they have stupid shaders set up, which fools them into thinking these great new features are crapola.

Lame.
 

 Ignorance should never be a sin. It can be cured with knowledge. There is so much to learn, that one person can't know everything. I learned something right now.

A python script to reset all the Diffuse values to .8 would be a VERY useful thing for Poser 8, don't you think?

someone wrote and posted one not so long ago... I've been using it in poser pro ever since..