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Glowing Head Problem, with subsurface scattering (interjection) addon, DS and Genesis Figure
Posted: 10 December 2012 01:55 PM   [ Ignore ]   [ # 61 ]
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Let me tell you first off, you’re going about it in the right way.  Playing with it is a battle.  I’m sorry, but 3D Rendering is HARD!  It’s never easy, no matter how you approach it o what tools you have at your disposal.  So, please understand, everyone goes though the kind of frustration you’re experiencing.

Secondly, I hope you’ll download the materials I put up for the purpose of comparrison.  Even if you hate them in your renders, comparing them to what you have now will help you understand what the different parts do.

Jacking down the specular is likely a good idea.  I have taken to using specular maps for strength on Ambiance, SubSurface and Specular.  Not just any maps, mind you, but high contrast maps like those that come with the Lana character.  I use those now almost exclusively on my figures, even if they came from someone else with specular maps included.  they’re usually not contrasty enough.  I have the specular on my characters now dialed down to 25% with a glossiness of 50% or less.

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Posted: 10 December 2012 01:59 PM   [ Ignore ]   [ # 62 ]
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sangit - 10 December 2012 12:34 PM

after carefully reading all the replies, this is what i come up with.
the shadow bias really solved the spotlight problem, but the overall look is still not very satisfying to me

i think the essential problem is that Daz Studio still lacks a suitable shader model for human skin or a kind of modular shader thing like the one they had as of poser 9

E.g. if there was a way to specify the sub surface scattering depth, the torchlight problem wouldnt occur. or even a possibility for using dermal and subdermal maps would be great. in a program that focuses on character design, things like that should be a priority wink

i dislike the way the highlights look, i have seen much better renders and i lack the knowledge to tweak them into something more nice.
also achieving that sexy “wax”-like skin look is very hard.

any ideas?


Ok first off; that “sexy wax” look you’re referring to probably is the SSS shader from Poser 2012. You can’t get that from Studio as far as I know.

Now for your image what you’ll want to do is check if you have a specular map plugged into the spec channel if not the interjection has three different ones. Plug one of them in the Spec colour or the Spec strength channel, this should give you better highlights. If that alone doesn’t help, lower the specular strength until you’re satisfied with the result.


Furthermore I’d adjust the rimlight so you get just a hair along the edge of the face instead of highlighting a good portion of the side of her head but that’s just me…

You can get some pretty amazing effects using this shader but it does take quite a bit of tweaking to get it right.

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Posted: 10 December 2012 02:13 PM   [ Ignore ]   [ # 63 ]
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If we could only convince Smith Micro to make Firefly available as a plugin for D|S… that would be soo sweet!

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Posted: 10 December 2012 02:28 PM   [ Ignore ]   [ # 64 ]
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wancow - 10 December 2012 02:13 PM

If we could only convince Smith Micro to make Firefly available as a plugin for D|S… that would be soo sweet!

Oh I don’t know I think 3Delight can do pretty much what I need it to do now if only I could wrap my head around that shader mixer I might actually make it do so :D

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Posted: 10 December 2012 02:39 PM   [ Ignore ]   [ # 65 ]
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Machieltje - 10 December 2012 02:28 PM
wancow - 10 December 2012 02:13 PM

If we could only convince Smith Micro to make Firefly available as a plugin for D|S… that would be soo sweet!

Oh I don’t know I think 3Delight can do pretty much what I need it to do now if only I could wrap my head around that shader mixer I might actually make it do so :D

I’m not even going to twy… not happening… I’ll take what you give me, though smile

Do you honestly believe you can mix up a shader to get the same kind of results?

Pretty sure that Firefly is Renderman Compliant… (correct me if I’m wrong) but isn’t 3Delight as well?  Wouldn’t a shader in 3Delight look about the same as one in Firefly?

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Posted: 10 December 2012 02:47 PM   [ Ignore ]   [ # 66 ]
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wancow - 10 December 2012 02:39 PM
Machieltje - 10 December 2012 02:28 PM
wancow - 10 December 2012 02:13 PM

If we could only convince Smith Micro to make Firefly available as a plugin for D|S… that would be soo sweet!

Oh I don’t know I think 3Delight can do pretty much what I need it to do now if only I could wrap my head around that shader mixer I might actually make it do so :D

I’m not even going to twy… not happening… I’ll take what you give me, though smile

Do you honestly believe you can mix up a shader to get the same kind of results?

Pretty sure that Firefly is Renderman Compliant… (correct me if I’m wrong) but isn’t 3Delight as well?  Wouldn’t a shader in 3Delight look about the same as one in Firefly?

I’m pretty sure I couldn’t and I’m not sure I’d want to. I think a lot of Poser renders look like they’re of silicon dolls which is not the effect I’m after.

What I would like though is some halfway decent (dare I sday good) bumps maps to go with a good SSS shader for Studio. and maybe some nice volumetric lights…

Oh and yes I would like to learn how to cook up my own shaders…

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Posted: 10 December 2012 03:36 PM   [ Ignore ]   [ # 67 ]
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Then you have my full support and I will be happy to test them as you deem necessary…

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Posted: 10 December 2012 04:03 PM   [ Ignore ]   [ # 68 ]
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3Delight is Renderman-complaint, Firefly isn’t (I long thought it was, but apparently not - it is however a REYES renderer, which is a larger grouping to which all Renderman-compliant engines belong if I understood correctly).

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Posted: 10 December 2012 07:34 PM   [ Ignore ]   [ # 69 ]
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where do i even choose what shader model is used for a selected surface?!
still tweaking for hours but it doesnt get any better.

a more poser-like sss shader would really be it! especially for the eyes.

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Posted: 10 December 2012 07:56 PM   [ Ignore ]   [ # 70 ]
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A huge part of this comes from just tweaking settings. I’m barely starting to scratch the surface on surfaces (bad pun, sorry) but so much of the power comes from playing with 1 setting at a time and just seeing what it does. Switching to the Human Surface Shader or UberSurface (both are included with DAZ) will give you SSS and a lot more control over some other parameters than the basic DAZ shader, plus I find that it just works nicer so I tend to use UberSurface (well UberSurface 2 in my case since I bought it) for just about everything unless I find that switching to it makes things worse and I can’t figure out why (had that with 1 surface which heavily relied on the reflection image for its colour and it just changed so much when I switched to US2 and couldn’t figure out how to get it back, so I just worked with the basic DAZ shader instead and got it way better).

Now need to start digging into SSS and skin settings in general as that’s something I really want to work on so this thread (and its sister African thread) are great.

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Posted: 11 December 2012 05:35 AM   [ Ignore ]   [ # 71 ]
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sangit - 10 December 2012 07:34 PM

where do i even choose what shader model is used for a selected surface?!
still tweaking for hours but it doesnt get any better.

a more poser-like sss shader would really be it! especially for the eyes.

Ok, so the thing that’s been bothering you is this….

Shadows. I’ve worked with the interjection shader for a while now and the effect I tend to see is not the effect I’m seeing in your image. Here’s why: I’m betting you use UE2 as an ambiant light while l;ighting your model with distant or even spot lights (or a combination) I’m also betting you have UE2 set at 100% intenstity and there’s your problem right there. Set UE2 to Ambient Occusion with soft shadows at 20% intenstity and only take it up when the image is too dark.

You could play a little with the colour of your other lights but keep in mind not to over do it; a hint of colour is enough in most cases. Try changing the background colour as well; a portrait against a black background tends to have more impact.

A lot of things have to come together for an image to work don’t stare yourself blind on just the surface.

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Posted: 11 December 2012 05:49 AM   [ Ignore ]   [ # 72 ]
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Just to give you an impression of what can be done with the interjection shader http://sadboy.deviantart.com/#/d5nssmb

Now this is just an quick render I did a while back when I first started messing with the shader mind nothing fancy.

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Posted: 11 December 2012 05:55 AM   [ Ignore ]   [ # 73 ]
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it is indeed UE2 but i dialed it down to 50%
will have to check into the other advice u gave me.

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Posted: 15 January 2013 11:46 PM   [ Ignore ]   [ # 74 ]
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Very interesting thread, specially by the way it begins with lot of beginner’s (like I am in realistic rendering) tries out. I have learnt a lot, thanks guys.

I am a DS4 user too, and was worried by the way Poser 2010 performs such great SSS results, much better than DS4, in Renderosity promo pictures.

At this point of doubt, I asked a pair of famous Rendo figures-sellers why their Daz-Studio promo were so poor compared to Poser ones. Their answers converged to something like this:

1.- “The difference comes mainly that our Poser renders are just professional renders and our DS4 renders are not. Have a look in the Rendo forum and see how people obtain disastrous result with SSS in Poser 2010 as well.” they said commonly.
2.- Their amazing velvet/Fresnel/reflexion/SSS results are usually obtained with a LOT of ligths, generally around 20-30 lamps of any kind, for a portrait.
3.- They generally generate AO using a separate pre-pass, with untextured models/props and a single GI lighting.
4.- They all said that DS4 has the same specs than Poser, and the different way the engine work is NOT the reason of quality gap, some of them even think that DS is better, but “chuttt ... don’t repeat I told you”, lol.

Well, I feel challenged, aren’t you? (and my best wishes to you for 2013).

Kindly, locusSolus.

PS: @Wancow: Of course I have the Daz Creeper. Is there some different texture for him anywhere? smile


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Posted: 16 January 2013 11:13 AM   [ Ignore ]   [ # 75 ]
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Yes mapped shadows with high bias settings are going to ‘miss’ a lot of geometry; and for SSS to function properly proper shadowing is a must… raytraced shadows with a little softness and a bias of around 0.1 is a good start.

Regarding the SSS depth thing - this is how far into the substance the light is allowed to pass before it scatters, generally in CM if the shader interface is written correctly.  So values around 0.1 are going to be ‘correct’ for human skin.  You’ll need to reduce the shading rate for the SSS to around ‘1’ to reduce artifacting.  Don’t forget to set the index of refraction to 1.3 or so.

I’ve recently been experimenting with the UberShader2 and had some good results with the SSS engine there.

Check the commentary on this image from my rendo gallery for specifics:

http://www.renderosity.com/mod/gallery/index.php?image_id=2401210

Wow, can’t believe this is my first post to the “new” forums, been away for a while!

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