My problem at the moment is creating lighting for scenes which has realistic shadows. I have adjusted light shadow settings, cast shadow settings on characters and other things, but shadowing still seens to be unnatural. For example, a character just above on another character (or touching), does not cast shadows on the character underneath correctly. The character below seems to not to pick up the shodow cast by the character above. This is apparent in most images in the Renderosity Gallary when two characters are close. Is this just a matter of aligning lights correctly. I use 2-3 infinite lights and 5-6 spot lights in most scenes. The issue of ambient lighting in Poser 5 seems to be a problem for me. Will upgrading from Poser 5 to 6 be a help?

Lighting is a tricky beast - it all depends on what you wanr in the scene. If you have specific light sources within the image (such as lamps or candles, for example), then you should make some attempt at casting light fro mthat direction. However, the standard 'studio lighting' set-up used for a lot of portraiture involves only three (possibly four) spotlights - key, fill, back (with bounce as a potential fourth). Poser 6 has another neat trick in its bag, with IBL. IBL takes a spherical texture map and applies it on a theoretical ball, which then casts light rays in towards the centre of the scene (not a great explanation, but it's the best I can come up with off the top of my head!) This is very useful if you have indirect lighting (light which has bounced off from other surfaces onto your subject), or for outdoors scenes where light is coming from all direction s at once, lessening the 'single shadow' situation. Lighting is such a huge topic that covering all the bases would likely entail a book all of it's own. There are a number of good tutorials out there on the web, though - Olivier over at RuntimeDNA has written several very good ones (just do a search for lighting in the Poser forums). At the end of the day, though, it's a very subjective thing, which can change with every image you create. There is no 'one way' to light a scene correctly. jonthecelt

Perhaps you have a few too mutch lights? Is it possible that one light "eats up" the shadow of the other light? Lighting in P6 is allmost the same as in P5. The only big difference is an additional pointlight.

Attached Link: http://www.renderosity.com/viewed.ez?galleryid=1187675

I think that the material shaders you use on figures and objects play as big a part as the lights themselves. Time taken experimenting in the material room can be well worth the effort.

I also think that the new lighting options in P6 help.

Using, IBL and ambient occlusion, I usually try to keep lights down to 2-4 max(sometimes you need specular only lights to pick out details that IBL doesnt give).
A limited lighting model also allows you to standardise to an extent the way in which you approach building shader trees for materials.

There's always the option of increasing/decreasing shadow intensity in a lights parameters.

Message edited on: 03/31/2006 06:10

Message edited on: 03/31/2006 06:15

"For example, a character just above on another character (or touching), does not cast shadows on the character underneath correctly. The character below seems to not to pick up the shodow cast by the character above." This also can be an issue with shadowmap size. Try to increase it to 1024 on the lights casting the main shadow, not more than on 1 or 2 though. Michal 4blueyes

bkmrk

Thank you jonthecelt, adp001, carodan, 4blueyes and mathman. Much appreciated.

Also, make sure you've got Cast Shadows checked under Rendering Options.

To clarify. The figure above has good shodows (lighted above and shadow below). Where the two figures meet, on the lower figure the shadows do not meet together and gradient away as would be natural. The lower figure it lit as if there is nothing shading it. I'll post an image when I get a chance. I think that adp001 hit the point. I may have too many lighting sources, but I feel I need this to get an even ambience in the scene. Thanks again.

Try to replace most infinite lights with spots. Move them very far away (500-1000 Y, -1000 to 1000 Z. -50 to 50 X, for example) but pointing to the middle of the scene. Infinite light is not stopped by solid objects. But a shadow is an unlighted area. Poser 6 users may use point light instead of spots. One pointlight and a spotlight near to the camera, both in raytrace mode, is enough for most scenes. Low memory usage and fast rendering :)

"Infinite light is not stopped by solid objects" This could very well be my problem, and thanks for the other suggestions adp001 & rest.

Whoa - be careful, adp001. When you said "Infinite light is not stopped by solid objects" what did you mean? Infinite lights absolutely ARE stopped by solid objects and produce shadows perfectly. Also you said "But a shadow is an unlighted area". This is not true - when I see my shadow on the ground on a sunny day, there is PLENTY of light hitting the shadow, so it is not "unlighted". It is the absence of the sun light which creates the shadow, not the absence of light altogether. So it can a shadow be partially lit in Poser. And to be realistic, it MUST be partially lit. I don't mean to be pedantic here, but since Ashley9803 is already having some problem that clearly indicates incomplete knowledge of how to get the desired effects of light and shadow, we don't want to give confusing information on top of it. Most of my scenes are lit by one IBL (P6 obviously) and one infinite light. IBL greatly simplifies the creation of workable ambient light. If you'll look in my gallery, the shadows are never total, but partial. Remember, ambient light is indirect light, light that bounced off another object, instead of directly coming from a light source. Ambient light should be very low. To do ambient light well in P5, you have to build up slowly. I suggest you turn off all your lights, Then turn each on one by one and render. Observe the contribution of each light and adjust. All ambient lights should be low. Then turn on all of your "ambient" lights, meaning everything but your main sources of light. Your objects should be clearly visible but not brightly lit. If any surface is bright, then it won't show a shadow from your main light. Also, if you are using shadows from your ambient lights, you probably want them to be soft edged and try reducing the shadow strength for these lights.

ashley9803, could you post a picture of the scene (and your light setup) you're having lighting problems in? It might help figure out why it's doing what it's doing.

Assuming you've got all the lights and shadow casting switches set properly, your problem is likely due to the lack of sufficient resolution in your ShadowMaps as 4blueyes suggested above, but here's some additional means of control.

Some basic shadow stuff first though.

The rendered shadows are generated based on the ShadowMap images created from the view of each light's Shadow Camera. You can select to view these cameras just as you can your other cameras.

The number of pixels in this shadowmap image calculated from these cameras views will determine the resolution of the rendered shadows. If the number of pixels in the shadowmap that cover the area casting shadows is too low, then the resulting cast shadows will be antialiased out and disappear when rendered. (This is often commented on with respect to shadows disappearing where objects contact the ground, making them appear to be floating.)

No problem though! You can, as 4blueyes suggested, try to increase the shadow resolution enough to get a solid, crisp edge, by increasing each light's MAP SIZE dial to generate a larger shadowmap image. This process is quick, and often is sufficient, but keep in mind that when doing so, you are exponentially increasing each light's actual shadowmap image file size and thus increasing the resulting memory requirements during each render. It can add up quickly.

However, to increase the effective shadow resolution, it is not always necessary to increase the shadowmap's overall size -- you can also simply change the light's shadowcam view to get more pixels where you really need them.

If you take a look at the example you used, and view the scene through the primary shadow casting light's Shadow Camera, I suspect you'll see your two figures as teeny-tiny spots in the field of view. That view, as a rendered image scaled to the size set on your light's MAP SIZE dial, represents all the pixels that will be used to create the figures' cast shadows. If they appear as tiny spots you aint got much to work with.

Now, this view is probably wide enough to include a ton of space, outside your real view of the scene, where you are not concerned about cast shadows.

SOOOOOOOOOOO, (finally getting to the real answer) try just zooming-in (Scaling) each light's Shadow Camera view to get more pixels covering your actual scene objects, and see if that does not result in sharper edged shadows that don't fuzz out and disappear when rendered.

or just paintem in with PhotoShop

Thanks guys. I'm really busy at the moment. Will post an example ASAP. Lighting my scenes to my satisfaction is my biggest headache. Will try your suggestions.

Here is an example of what I mean. This is using default P5 light settings. The two figures are close to touching. The bottom of the figure (arm) above, has nice shadowing on the lower part of the arm. The top of the arm below, where the shadow meets the lit area, you would expect to have some shadow from dark to lighter, esentially a reverse smaller version of the shadowing of the above arm. It doesn't, it goes from lit to black. Even though these arms are touching, you would expect to see some shadow gradient.

Seems to be a Poser issue, try moving the two figures a little further apart, you should get shadows then. I think it's because the "bottom" part of the upper arm's geometry is intersecting with the geometry of the lower arm, somehow preventing normal shadow generation. I'm not sure how to fix it, but I do believe that's the cause. Maybe someone more knowledgable can help?

Ah now with your picture here I understand the problem. The darkness on the bottom of the upper arm is NOT a shadow. It is dark because the light is not shining at it, it is from above. I can see SOME shadow on the lower arm from the light being blocked by the upper arm. But its only where the arms are far apart. This is the fault of the shadow min bias. Decrease the bias - you'll get shadows on objects that are close together.

Thanks bagginsbill and modus0. Will try as you suggested. The difference between "shadow" and "dark because the light is not shining at it" is a fine one, but I see your point. Will muck around with shadow bias settings and see what happens.

Here's another way to think about it. If you render without shadows, the underside of those arms will still be dark. So those areas of darkness must NOT be shadows, because if they were, you would have turned them off.