Leonardis opened this issue on Sep 28, 2008 · 9 posts
Leonardis posted Sun, 28 September 2008 at 4:22 AM
I was hoping that upgrading to Poser 7 would fix this, but it's even worse than Poser 5/6. Maybe I just haven't read the manual thoroughly enough. It doesn't matter whether I use Poser 4 or Firefly rendering, or what settings I use, or whether I use infinite or spots, or any shadow method, the shadows from even a simple object are not in alignment. For example a simple cube on a simple floor. The shadow NEVER intersects with the object. It is permanently displaced.
The only way to fix it is in photoshop after render. The worst example of this is with table legs or long thin objects. In this case the shadow doesn't even meet the bottom of the object. This problem has been driving me nuts for years but I thought it was just a flaw in Poser. Sincerely hoping it isn't so could someone please explain how to adjust Poser so the shadows fall as they should, guaranteed, every time.
Thanks.
Leonardis
IsaoShi posted Sun, 28 September 2008 at 5:11 AM
Can you post an example render? I've never seen any trouble like this in any version of P7.
"If I were a shadow, I know I wouldn't like to be half of
what I should be."
Mr Otsuka, the old black tomcat in Kafka on the Shore (Haruki
Murakami)
geep posted Sun, 28 September 2008 at 5:48 AM
Works pretty good in Poser 6 for me.
cheers,
dr geep
;=]
Remember ... "With Poser, all things are possible, and poseable!"
cheers,
dr geep ... :o]
edited 10/5/2019
pjz99 posted Sun, 28 September 2008 at 6:41 AM
In the case of using depth-mapped shadows, what you are seeing is called a "light leak" or incorrect shadow offset. Depth-mapped shadows can always suffer from this kind of flaw depending on the arrangement of objects in the scene. You can adjust min shadow bias and try to minimize the effect, but can't ever prevent it from happening. It is one of the fundamental flaws of using depth-mapped shadows. There are other flaws with depth-mapped shadows aside from that, notably various kinds of artifacts and fundamentally wrong blurred shadows.
http://www.peachpit.com/articles/article.aspx?p=486505&seqNum=5
They're okay for low quality work, or cases where speed is a high priority, but imo if you want high quality lighting you should get away from using depth-mapped shadows entirely. The flaws I'm talking about are not particular weaknesses of Poser, they are problems in any rendering application that uses depth-mapped shadows. This is an example scene containing a light setup that imo is quite a bit more realistic than any of the default lighting setups, feel free to play around with it.
http://www.renderosity.com/mod/rrfilelock/download.php?fileid=33527&key=8122
Connatic posted Sun, 28 September 2008 at 10:22 AM
Did you try adjusting the shadow-cameras?
Leonardis posted Sun, 28 September 2008 at 7:38 PM
Quote - Image fuzzy? ... Try clicking on it ... ;=]
Works pretty good in Poser 6 for me.
cheers,
dr geep
;=]
Hi Dr Geep. I've learned a lot from your excellent tutorials over the years, so this is a good opportunity to say thank you. But I'm surprised you haven't seen any misaligned shadows. Maybe you are rendering with Firefly and ray tracing. When I do the problem doesn't arise, but sometimes I prefer Poser 4 type rendering, especially when there is less time available and a simple render is needed. So, as pointed out elsewhere in this thread, it is with Mapped shadows that it occurs.
Unless I very very carefully setup a shadow light camera and tweak it to a very precise angle and coverage the shadows are nearly always non-aligned. I can't post an example at the moment because I am not at home. What I don't quite understand is that an "infinite" light is meant to emulate the sun, and you'd have to travel a very large distance to see a different alignment of shadowing from the sun. So it surprises me that in a relatively small room the shadows are way off unless you focus the shadow cam very tightly on the objects you want shadowed.
It seems from other posts that this is an inherent fault with renders which are based on non ray traced shadows. Or have I missed something?
Leonardis
Leonardis posted Sun, 28 September 2008 at 7:42 PM
Quote - Did you try adjusting the shadow-cameras?
Answering the other posts including the link to the tutorial, for which thanks: Yes I have come to realise that the key is setting the shadow cam very accurately, or using multiple spots with narrow cones pointing at the individual objects needing an accurate depth mapped shadow. I hadn't realised before how important this is. One good thing about Poser 7 is that, on my now more powerful computer, it seems to render in Firefly a lot quicker than Poser 5 and 6, so I expect I will use this method more in the future.
But it's a shame that depth mapped shadows are a bit hit and miss in this regard.
Leonardis
geep posted Sun, 28 September 2008 at 8:25 PM
One can use Ray Trace shadows with the Poser 4 renderer if one sets the light's "Shadows" to Ray Trace. This may actually render faster than depth mapped shadows because no shadow map(s) need to be generated.
If one wants to use depth mapped shadows ... then one needs to take care when setting the "Shadow Blur Radius" and the "Shadow Minimum Bias" parameters in order to achieve a satisfactory result.
cheers,
dr geep
;=]
Remember ... "With Poser, all things are possible, and poseable!"
cheers,
dr geep ... :o]
edited 10/5/2019
pjz99 posted Sun, 28 September 2008 at 8:32 PM
Depth-mapped shadows are hit and miss in many regards. They are never accurate or realistic under any circumstances, although their flaws can sometimes be hidden.