360 Skeleton SSS Test

[Vertex Pusher]

Here is a simple 360 degree SSS test I made last night using Brecht's patch for Sub Surface scattering (about 3.6 megs).

I had just finished roughing in the various parts for my skeleton and was going to tweak it some more (the part I hate the most) and maybe rig it but then Brecht comes up with this amazing implementation, so I had to see what it might look like on some of my projects .
Here is a still test render :

And then I wanted to see it animated in 360 in full length and to see how it would look like implemented . So here is my first "animation" .

Unfortunately I choose a custom format for the avi jpeg (BTW avis with codecs won't let you do this I learned the hard way) . It has a 600 x 1200 aspect ratio (it's a 360 of a skeleton in black space I don't need all the blank space in the file) so it might not play in some of the usual media players out there . VLC works fine and so does the old Windows Media Player (you just won't be able to zoom in with VLC unless your monitor is set for larger then 1200px hight ratio) .

And if all else fails you can use Blender's Video Sequence Editor Just set up two sequence editor windows and set one of them to view the clip . And also change the aspect ratio to 600 x 1200 in the Format panel in Scene (F10)- otherwise the movie will play squashed .

It's a short simple 360 model view so you might also want to enable looping in the player you use or Shift-D to add additional clips in the Video Sequence Editor . I tried to make the rotation as smooth as possible between the start and end .

The settings I used for the SSS was the default marble material in the patch with two lights, a spot in the front and a lamp in the back, both at about 45 degrees to the model . The back scattering effect on the ulna and radius (lower arm) and the fibula seems a little too intense but that is probably just the idiot way in which I set up the scene . But overall if I say so myself a pretty cool and pretty "natural" looking effect . All thanks to Brecht .

[blazer003]

In the video I'm not really noticing the SSS effect. It is either extremely subtle, or perhaps you forgot to include it? Are you going for real bone SSS or plastic skeleton SSS? Maybe it was just because I was expecting plastic skeleton SSS, as that's what your still image looks like. It's a good skeleton model though.

:edit:

As I view it again, I see the effect. I think that the specularity of the skeleton doesn't really match the amount of SSS used. In my mind, something that specular would A. be metal and have no SSS or B. be plastic and have more scattering. I think if you put a rough bone texture on him it would look about right.

[BlackBoe]

SSS != awesome. I notice the SSS, but the rest of the material really doesn't cut it for bone.

[Vertex Pusher]

Well yes both of you are right of course . The materials do not work as a bone material (it's the default generic material except for the intercostal cartilage part and the SSS is the default "marble" settings in Brecht's patch) - this project is still at stage where I am still tweaking the mesh like I said above but I was just very excited to see how the SSS might look "animated" on a complicated structure . The texturing and material parts are all very new to me and right now I'm working on the rigging/animation side of things . So I can live with the "plastic medical skeleton" material for now ... But thanks for your comments .

[PapaSmurf]

I dont think bone has any sub-surface...it's bone. It has some translucency, where thin bones let light through...but it's like calcium, isn't it? Cartiledge has sss, so maybe you're modeling a shark-human.

[Cognis]

PapaSmurf is right, cartilage has SSS, bone no. But where did you get the model? Very nice skeleton, you just had one in the closet?

[BlackBoe]

Bone is heavily porous.

[Vertex Pusher]

@ PapaSmurf : From what I understand SSS is an effect of light on a surface that depends on the density of the surface . And like Blackboe said bone is generally porous so there is SSS depending how it is lit . I mean porcelain looks good with SSS applied and it is usually more dense then bone . Besides which I recall a SSS example for the Maxwell (?) renderer that used a skull which looked very good IMO .

@Cognis : The skeleton model is my own . And Like I said in my first post I am in the process of tweaking it right now . I made it to point out some anatomical issues related to 3D and animation . I should have it rigged pretty soon .

[Cognis]

Originally Posted by Vertex Pusher @Cognis : The skeleton model is my own . And Like I said in my first post I am in the process of tweaking it right now . I made it to point out some anatomical issues related to 3D and animation . I should have it rigged pretty soon .

Will it be publicly available? I know it sounds creepy, but I love skeletons (okay, really really creepy....)

[Dani]

I do beleive bone has SSS. It's been a year since I haven't held a skull or any bone but I clearly remember looking inside a skull and noticing that light passes easily through at the occipital, temporal and orbital regions... that's for anatomy, and that's more about translucency than SSS. However light does scatter in the bone, as it does in teeth...
Anyway, sayin g this won't make your material look better. Tweak the colors and the specular, and the light setting too!

Dani

[Vertex Pusher]

@Cognis :A definite maybe . This is the first part of a larger project I am working on and I'm not sure if this will be a part of the final product and also I am a bit ambivalent about letting loose something that I might encounter later ... and give me the shivers for having produced such a thing in the first place (I modeled this with subsurf turned on so the geometry is a little wicked if you turn it off )

@ Dani : Or should I call you Hamlet ? ... "held a skull" indeed ... But as far as the bone/SSS issue at hand I do recall a long time ago seeing a real skull and it was under very poor lighting (florescent) and the way it was preserved didn't make it look like it had any light scattering effect on it ... so maybe the way the bone gets preserved determines if the bone will scatter light or not . I wouldn't apply SSS on fossilized bone for example .
And I will say once again with some embarrassment that yes the materials/lightings are very poor and I didn't put any work in them ... I just wanted to test Brecht's cool patch on some complex geometry "animated" somewhat . The effect towards the end when it rotates back to face the front is all due to Brecht's work even despite the poor materials .

And also just to point out something I just noticed for any one interested, you might try using the video sequencer in Blender to view this . I just noticed that depending on the player used the effect/quality varies probably due to the odd format size I used . Just remember to change the aspect ratio to 600x1200 .

[mrmunkily]

Some thin "membranous" bone is semitranslucent.

In general, though, bones that are large enough to have marrow (i.e. ribs and larger) won't have appreciable backscatter. The "core" is too dense and absorptive. Side scatter is a formal possibility but under normal lighting conditions it's going to be really minimal.

More important for bones is a properly lit diffuse and rough surface. I've looked at a lot of bones. none of them are smooth. The only places that bother to be smooth are the articular surfaces, which are, of course, not bone at all. Bone is also, as Blackboe says, quite porous. Often the surfaces are covered in grooves, fissure, lumps... you get the idea. Texturing and displacement (probably) are going to be your friends.

But it's a nice wax skeleton!

[TroutMask]

bones will allow more light to pass through when they are dried out.

i handled human bones in college (i carried around a pelvis in my backpack for about a week) and they definitely have SSS. when bones are dry, they are much lighter than one would think, almost like styro foam but not quite.

[Cognis]

Originally Posted by TroutMask bones will allow more light to pass through when they are dried out.

But is this through an effect like SSS? I would suspect something more like pinpoints of light seeping through large pores, or just translucency. SSS builds on lower layers reflecting part of the light, is that what happens in bones?

(i carried around a pelvis in my backpack for about a week)

I have to ask.... exactly why?

[TroutMask]

I have to ask.... exactly why?

art school. anatomy project. the professor lent out all the bones of his demonstration skeleton but cautioned us not to show anyone because apparently one needs some kind of permit to transport human remains.

in answer to your other question, i'm not sure.

[Cognis]

Originally Posted by TroutMask apparently one needs some kind of permit to transport human remains.

Tsk tsk. Government bureaucracy, keeping us from stocking kidneys and skulls.

Btw., I like your art teacher already

[Vertex Pusher]

But is this through an effect like SSS? I would suspect something more like pinpoints of light seeping through large pores, or just translucency. SSS builds on lower layers reflecting part of the light, is that what happens in bones?

Funny a debate about if bones have SSS or not . And well I have thought about it some more and decided that it probably has some thing to do with how calcium diffuses light . If you think about it other common objects used to test/display SSS other then human skin are shells - which is composed purely of calcium . I don't think that there is a translucency scale like there is for transparency (nothing like an IOR scale) available (is there?) .
But IMO bones do look better with SSS then not so that is why I applied it in this case . Especially in the skull where the bone can get so thin as to diffuse light in a manner appropriate for SSS . Even if in the current set up it looks like cheap plastic/wax (tho one of my favorite anatomy reference is a book that documents a museum in Florence that has a collection of wax reproductions of anatomical features from the 19th century )

[cuervo]

my god

beautiful modeling, and though i could point out the flaws on the material, thats been done before. For my two cents, i have never actually seen real human bones (excluding an old skull, but that was so long ago that i didnt even know what sss was ), but it only makes sense that they would have sss. I would also agree that the amount of subsurf depends on how much marrow is in the bone, so dry bones would have more scattering. i think that, while the use of sss is a good idea for this, the bones may currently have a little too much. also, i would suggest making the costal cartilage less red (though i really dont know what color real cartilage is).

and i would loove to get my hands on this model. eh? eh?

edit: oh, and i think a real spine has more variation in the width (on the coronal plane, i think its called?) like so.

another edit: and i would like to comment on your stunning modeling of the bones with more subtle imperfections on the surface, like the humerus, radius, scapula, coccyx, femur and especially the skull. great work! (but i think the heads of the humerus and femur are too perfectly spherical, in case you hadn't noticed).

[cuervo]

heheh... i just realized how old this thread is....

i suppose i should've realized since you were talking about the 'new' sss feature....

[WannaBCreative]

There seems to be a bit of debate going on in regards to fi a bone has sss or not. Some of you have hinted that it shouldn't because its mostly calcium. Here is a tutorial on SSS....guess what they decided would make a good tutorial on sss? Milk. Interesting fact: 1 cup of milk can contain anywhere from 103mg of calcium (non-fat milk) to 321mg of calcium (2% or 1%milk).

So I'm guessing the arguement that bone cannot have sss because it is mostly calcuim has been laid to rest. I'm no expert, and have no wishes to work with sss at the moment, so I wont put any more effort into figuring this out, but you guys did present me with an interesting question so I researched a bit. However I couldn't find anything that states bluntly bone has sss or not. As a matter of fact google bone sss. The only noteworthy return leads to this thread. So if you guys ever do come to a conclusion on this......the rest of us will probably read about it at one point or another lol.

Originally Posted by cuervo heheh... i just realized how old this thread is.... i suppose i should've realized since you were talking about the 'new' sss feature....

Doh.....it came up in as a new post so I paid no attention to the dates lol.