I basically have a floor and a ceiling made from the standad square prop and walls with windows in them (Joe's Window Walls) I have a spotlight shining straight in the window which cast shadows through the window and on to the floor. Works perfectly. How ever there is a big chunk of light where the floor meets the wall almost like it is seeping through (Like light showing under a door). I have raised the floor so it well over laps the wall but its still happening. Any ideas? :) Thanks!

Are you using a bump map? I've had it happen to me when I used one, and I think Anthony Appleyard discovered the same thing. One of Poser's lighting "features".

No, no bump maps. No maps at all actually. It is prolly some light setting I have. Still getting used to the lights. :)

Attached Link: http://www.annsartgallery.com/fp.html

Believe it or not, I've encountered this in Bryce as well. Which is partly why I use IMSI floor plan.

Light leaks and shadow leaks are the result of faulty calculations because of the way the polygons on the floor match up or rather, do not match up with the wall polygons. The explanation in 3D Lighting, Arnold Gallardo is so jargon ridden and unclear, I am not sure he understood it. But the figures in the book show it right enough. The way to reduce it, seems to be, to have high poly props, quads rather than triangles - especially no acute triangles - and for the polys on the two surfaces to be done in parallel. Two planes that meet at right angles and the plane cutting across the open areas of the other's polygons? Render engines seem to have a problem intrepreting light and shadow over the surface of the transsected polygons - partially ignoring the effect of the prependicular plane on the light on polygons who live on either side of the perpendicular plane. But, as I said, the explanation is clear as mud. The book focuses on TS, Max and LW - so if those render engines have this problem, it would be unrealistic to expect Poser or Bryce to not share in it.

This happens with items also. Like this object built with Anim8or. It seems as when "squared" objects are imported into Poser the edges are "bent". A square look more like a pillow. I don't know enough to have a solution to this. The only way I was able to fix the floor/ceiling problem was to use a square from primitives in Props instead of a cube or such. But the problem with the objects still remains.

Thanks peoples :) Its good to know it's not only me that has probs hehe. I got about half of what Arnold Galardo was saying Jaager hehe. You were right about the Jargon lol. Tiny that might help actually. i used a cube for the floor instead of a square so will give it a go :) Cheers!

If you use the square prop, but you still want a window, can you just imbed the square in the lower part of the window-wall, where it intersects with the floor?

Sounds like symptoms of antialiasing of the shadowmap. See this thread for a similar problem and solution by by adjusting your shadowcams.