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Somethings to Consider when starting to learn CG
Posted: 06 February 2013 09:31 PM   [ Ignore ]   [ # 91 ]
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Are you using the Global Illumination setting for UE2 by any chance?

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Posted: 07 February 2013 05:48 AM   [ Ignore ]   [ # 92 ]
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No, indirect lighting with soft shadows. I had originally loaded in UE in GI mode, so no sphere was loaded, but switched modes after the crippling render times.

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Posted: 07 February 2013 05:58 AM   [ Ignore ]   [ # 93 ]
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Ok IDL and GI both need settings to be super sampling….so the shading rate of UE2 should start at 0.20 - 0.10 or even as low as 0.01. The Advanced Render Settings Shading rate drop down to 0.10 or lower.

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Posted: 08 February 2013 05:38 AM   [ Ignore ]   [ # 94 ]
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Okay, this is what I’m getting with a shading rate of 0.01 for UE. The banding is only in the arms, although there’s some in her legs too, so I’m going to double check if I have anything odd going on with my skin materials on those mat zones. Also see that I still have some hair issues but it’s pretty minor at this point.

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Posted: 08 February 2013 06:20 AM   [ Ignore ]   [ # 95 ]
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Are you using uber surface on the skin the banding can sumtimes be got rid of by increasing the subsurface scale.

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Posted: 08 February 2013 07:08 AM   [ Ignore ]   [ # 96 ]
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scorpio64dragon thx I keep forgeting that one.

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Posted: 08 February 2013 11:11 AM   [ Ignore ]   [ # 97 ]
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I should have asked…do you know what this Scale value represents?

If not it is the thinkness of the surface that the SSS has to penatrate. When using pwSurface a value of 1 works well. I see DT uses 1.70 for Uber Surface in his Interjection products. I have also noticed some skin textures sets coming in loaded at a value of 4. IMHO I think this is way to thick for human skin.

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Posted: 09 February 2013 01:56 PM   [ Ignore ]   [ # 98 ]
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Uber Surface 2 has a SSS shading rate setting and I think that’s the culprit. I stumbled across it while checking the SSS scale (was defaulted at 1) and in a bit of confusion between samples and shading rate, I cranked it up to 128 from its default of 32 and got this horrible result. I’d discarded the changes there and had left it as I was discouraged from the lack of progress.

But, I just had the flash of realization that low is what you want for shading rate so I’m re-rendering now with all of the surfaces dialed down to 1 for SSS shading rate, will post the result when that’s done. Given how much worse it got from cranking it up I’m hoping this is the correct slider and that dropping it from 32 to 1 will be a good improvement.

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Posted: 10 February 2013 08:39 AM   [ Ignore ]   [ # 99 ]
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I have never needed to change the SSS Shading Rate before and I have used some fairly advanced shaders and lighting and never come across this issue personally before.

Are both light sources set to 0.10 shadow Bias?

As for the eyes this is Genesis isn’t it? If it is I haven’t done much works with Genesis but I do know it does have a Cornea surfaces like the Gen4 figure have and that would have been easy to advise.

Since I can’t even run DS4/4.5 I can’t help further.

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Posted: 10 February 2013 11:12 AM   [ Ignore ]   [ # 100 ]
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Subsurface shading rate did the trick, dropped that down to 1 and this is what I got.

I double checked my settings and both the area light and UE were set to 0.10 for shadow bias.

For the eyes, yes as far as I can tell the Genesis surfaces are the same as Gen4 surfaces. I was applying the reflections on the cornea material. I was using 0% opacity, 100% reflection, raytraced reflections with fresnel active. I think that’s the main pertinent settings. Might have to try one with fresnel turned off. I’d experimented quite a bit with just zoomed in on the eye and it seemed to improve things but zoomed out it looks bad so maybe that’s the culprit.

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Posted: 10 February 2013 11:33 AM   [ Ignore ]   [ # 101 ]
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Well I learned something myself today, thanks adacey.

Well the last time I used Genesis it didn’t have a Cornea surfaces at all.

If that has changed then I will dig out the settings of the Cornea at least.

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Posted: 10 February 2013 12:10 PM   [ Ignore ]   [ # 102 ]
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Thanks Szark, that’s a big part of why I’ve been trying to keep this thread alive, there’s a lot of useful info in it already and I figure if I’m working through a problem then odds are good somebody else is hitting the same issue.

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Posted: 10 February 2013 12:20 PM   [ Ignore ]   [ # 103 ]
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and I really appreciate that adacey thank you.

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Posted: 12 February 2013 08:29 AM   [ Ignore ]   [ # 104 ]
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This is the problem with not having access to DS4.5 I had no idea they brought back the Cornea surface for Genesis…I just had it confirmed.

For me this is good news but how to set it up better.

The first thing to do is turn OFF the Specular “Multiply Through Opacity” setting, What does this do?

With Multiply Through Opacity turned OFF lets the render engine know that there is a transparent object/surface in the scene the will need specular highlights and Reflections. This is also true for Glass. If you using low opacity and high reflections and specular highlights for any surface/s and not using opacity maps turning this OFF will help achieve those results. If you are using a Opacity map then this needs to be ON otherwise you will get reflections and/or highlights on parts that should be invisible. smile

Opacity between 40 and 50% works quite well if you are using a reflection map.

If using a reflection map then place the reflection map (usually a black and white map) in the Diffuse Colour and Opacity channels still turning OFF Multiply Through Opacity in the Specular channel

If you are not using a reflection map and want crisper looking eyes try 0% opacity and as long as your light set up is good enough and you turn OFF Multiply Through Opacity you should get good reflections. I am doing an animal image at the moment and even at 0% Opacity I am getting nice reflections on the cornea.

Reflection colour 255,255,255 white
Reflection Strength (for real reflections we do need something in the scene to reflect) 100% or lower to taste. If using a reflection map then 0% will be best. smile

Ok hope that helps with the Cornea surface.

Oh yeah if you want help with the other parts like with SSS for the whites etc just yell. I am still here to help but with having to wait to get to use the laptop makes it hard to get online much these days.

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Posted: 12 February 2013 11:18 AM   [ Ignore ]   [ # 105 ]
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adacey - 10 February 2013 12:10 PM

Thanks Szark, that’s a big part of why I’ve been trying to keep this thread alive, there’s a lot of useful info in it already and I figure if I’m working through a problem then odds are good somebody else is hitting the same issue.

Thank you @adacey and @Szark for keeping this thread active! I’ve learned a great deal from it. I lurk for the most part but I wanted to chime in and let you know that I’m appreciative.

 

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