Fiddling with Iray skin settings...

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  • Gr00vusGr00vus Posts: 366

    I've been reading this thread and the show us your iray renders threads in hopes of improving my skin shaders. I'm stuck at a place where I could use some help. Below I've posted my current shader settings and a resulting render. I have not dealt with translucency yet (it's weight is set to 0). So I need help with 2 things. 1) Does what I have now, pre-translucency make sense, does it work? 2) How should I set up the translucency? Assume a caucasian skin tone is the target. I've experimented with a few things, but none of them are satisfactory. I'm using the translucency, specular, sss, and normal maps that came in the beautiful iray skin for g2 product. The texture is Bree with reduced vibrance. I'd appreciate any feedback. If possible, keep it simple. I'm still reading through much of the info already stated, so the lengthy descriptions/explanations don't really need to be repeated again if possible.

    Thanks.

    test-render-1

     

  • Arnold CArnold C Posts: 740
    edited October 2015
    Gr00vus said:

    Does what I have now, pre-translucency make sense, does it work? 2) How should I set up the translucency? Assume a caucasian skin tone is the target. I've experimented with a few things, but none of them are satisfactory. I'm using the translucency, specular, sss, and normal maps that came in the beautiful iray skin for g2 product. The texture is Bree with reduced vibrance. I'd appreciate any feedback. If possible, keep it simple. I'm still reading through much of the info already stated, so the lengthy descriptions/explanations don't really need to be repeated again if possible.

    Thanks.

    Hi Gr00vus. I guess that will be my standard reply: Almost ©... So, if you'll trust my knowledge, I'll put it it as short as it gets:

    - Glossy Layered Weight: if you're going for a combined Base and Top Coat specular reflection setup, set this to 1.00 then.

    - Glossy Color: you can remove the specular map there, doesn't meet PBS requirements. The black in that should be at RGB 58, 58, 58 maximum. It's at RGB 70, 70, 70, so, too much, --> trashbin. Another standard reply: Specular Reflectance from Skin Is White! Set it back to RGB 255, 255, 255. You have your Glossy Specular to adjust that to a correct setting.

    - Talking about Glossy Specular: that needs to match your Refraction Index (looks good btw, is in a considerable range). I assume that's a 1.410 there, so it will be a 0.028924 for each the red, green and blue RGB color channel.

    - Glossiness: too high, try a 0.30 there.

    Top Coat Weight: too high, will blow your diffuse and translucency, try a value from 0.35 to 0.45 there, can be a bit lower if that suits your needs.

    - Top Coat Color: don't have a clue what that strange map should resemble there. But since it's most obviously not a PBS Specular Map, remove it and set the color back to standard RGB 255, 255, 255.

    - Top Coat Glossiness: same as Glossiness on the Base, too high, 0.30.

    - Top Coat IOR: depends on what you want your Top Coat to simulate: for stratum corneum 1.52 - 1.55; for sebum 1.5.

    Top Coat Thin Film IOR of 1.41 doesn't make any sense if you don't determine Top Coat Thin Film. Thickness of that would be around 20800, and IOR 1.5. That's for if you want to have actually a thin film (sebum). Set Top Coat IOR to between 1.52 - 1.55 then 

    Translucency: common method is to use a red color to mimic the blood contained in the dermis as Translucency Color. What kinda red can be target of a discussion, some refer to RGB 255, 0, 0, some to RGB 167, 0, 0. A picked color value from a veneral/arterial blood mix looks like RGB 180, 65, 65. Translucency Weight for caucasians is at around 0.45 - 0.50. You'll also need a "Shadow Catcher" (Color Catcher) mask like explained by MEC4D in the "Show us your Iray Renders" threads to avoid the brows of your texture map getting tinted by your translucency color. The "Part II" one if I remember correctly, at around page 35. For the Volume settings you can read through the postings on this thread.

    Could just be the tiny thumbnail, but your reduced vibrance looks a bit odd there on Bree. At which strength did you reduced the vibrance? Below is the Bree face texture at -60.

    Bree.jpg
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    Post edited by Arnold C on
  • Gr00vusGr00vus Posts: 366
    edited October 2015

    @ ArnoldC - I've tried your suggestions (to the best of my understanding) and here's the result so far:

    settings 2

     

    render-2

    So, I haven't gotten things quite right I think.

    When you say "Volume settings" - are you talking about bump and normal maps, or something else?

    Also, I assume the top coat thin film thickness you state of 20800 translates into 0.208 as the parameter for the top coat thin film weight?

    Thanks again for the help. Please be patient with me. smiley

    Arnold C. said:
    Gr00vus said:

    Does what I have now, pre-translucency make sense, does it work? 2) How should I set up the translucency? Assume a caucasian skin tone is the target. I've experimented with a few things, but none of them are satisfactory. I'm using the translucency, specular, sss, and normal maps that came in the beautiful iray skin for g2 product. The texture is Bree with reduced vibrance. I'd appreciate any feedback. If possible, keep it simple. I'm still reading through much of the info already stated, so the lengthy descriptions/explanations don't really need to be repeated again if possible.

    Thanks.

    Hi Gr00vus. I guess that will be my standard reply: Almost ©... So, if you'll trust my knowledge, I'll put it it as short as it gets:

    - Glossy Layered Weight: if you're going for a combined Base and Top Coat specular reflection setup, set this to 1.00 then.

    - Glossy Color: you can remove the specular map there, doesn't meet PBS requirements. The black in that should be at RGB 58, 58, 58 maximum. It's at RGB 70, 70, 70, so, too much, --> trashbin. Another standard reply: Specular Reflectance from Skin Is White! Set it back to RGB 255, 255, 255. You have your Glossy Specular to adjust that to a correct setting.

    - Talking about Glossy Specular: that needs to match your Refraction Index (looks good btw, is in a considerable range). I assume that's a 1.410 there, so it will be a 0.028924 for each the red, green and blue RGB color channel.

    - Glossiness: too high, try a 0.30 there.

    Top Coat Weight: too high, will blow your diffuse and translucency, try a value from 0.35 to 0.45 there, can be a bit lower if that suits your needs.

    - Top Coat Color: don't have a clue what that strange map should resemble there. But since it's most obviously not a PBS Specular Map, remove it and set the color back to standard RGB 255, 255, 255.

    - Top Coat Glossiness: same as Glossiness on the Base, too high, 0.30.

    - Top Coat IOR: depends on what you want your Top Coat to simulate: for stratum corneum 1.52 - 1.55; for sebum 1.5.

    Top Coat Thin Film IOR of 1.41 doesn't make any sense if you don't determine Top Coat Thin Film. Thickness of that would be around 20800, and IOR 1.5. That's for if you want to have actually a thin film (sebum). Set Top Coat IOR to between 1.52 - 1.55 then 

    Translucency: common method is to use a red color to mimic the blood contained in the dermis as Translucency Color. What kinda red can be target of a discussion, some refer to RGB 255, 0, 0, some to RGB 167, 0, 0. A picked color value from a veneral/arterial blood mix looks like RGB 180, 65, 65. Translucency Weight for caucasians is at around 0.45 - 0.50. You'll also need a "Shadow Catcher" (Color Catcher) mask like explained by MEC4D in the "Show us your Iray Renders" threads to avoid the brows of your texture map getting tinted by your translucency color. The "Part II" one if I remember correctly, at around page 35. For the Volume settings you can read through the postings on this thread.

    Could just be the tiny thumbnail, but your reduced vibrance looks a bit odd there on Bree. At which strength did you reduced the vibrance? Below is the Bree face texture at -60.

     

    Post edited by Gr00vus on
  • Arnold CArnold C Posts: 740
    edited October 2015
    Gr00vus said:

    @ ArnoldC - I've tried your suggestions (to the best of my understanding) and here's the result so far:

    So, I haven't gotten things quite right I think.

    When you say "Volume settings" - are you talking about bump and normal maps, or something else?

    Also, I assume the top coat thin film thickness you state of 20800 translates into 0.208 as the parameter for the top coat thin film weight?

    Thanks again for the help. Please be patient with me. smiley

    Hi Gr00vus, you're welcome. For starters, and to make yourself familiar with Iray shader setup, I'd recommend you may first try to work with the original "Bree" textures. For creating textures for Physically Based Shading use you'll require a certain working space on your graphics software, for Photoshop it has to be setup like shown in the picture below f.e.

    MEC4D's method is one way to make up skin, and I'm quite sure she doesn't tell us all her little secrets, which is from a mercantilist point of view understandable. But in any way you need to have a "shadow catcher/color catcher" texture in you Translucency Color slot, or it will come out too strong, as your render shows. Without one, Translucency Weight should be set way lower and shouldn't exceed 0.3. You'll still have the problem of tinted eyebrows though.

    "Volume settings" are the Subsurface Scattering, or short SSS settings (absorption and scattering), we here discussing about atm.

    No, the 20800 doesn't translate, that'll be the value you put into. wink For starters, just drop thin film for a moment and set your Top Coat IOR to the default 1.5, until you got the basics to what you like, and then experiment with adding one.

    I know, the "Pixar Campus" HDRi is a nice one, and has been something like a standard used back in the days, but unfortunately the Luxo Jr. statue provides some additional lighting to the scene, which could make your skin look nicely in that distinct lighting soulution, but horrible in another, so it's therefore a bit unsuitable for shader setups, as it would be the default Sun-Sky.

    Andy recommends to use some 5000 K meshlights for that.

    I recently tried some of j.cades Painter's Lights (now I know why his name in this thread sounded familiar :D) and the "Classical" ones seem to be suitable for that purpose, too.

    PS_Workspace.jpg
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    volume_settings.jpg
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    Post edited by Arnold C on
  • AndyGrimmAndyGrimm Posts: 910

    Light and SKIN ... i start with 5k light color and not 6500k......  color neutral light is around 4500 - 5000k since a long time in the photo and print industry (our reference images!). I noted that DAZ textures looking better in 6500 and this is one of the reasons why they are to much red saturated (compensating the blue in 6500!. in hdri ligth which is not shot around midday sunlight with  overcast....direct sunlight is around 5k!



     

    colorchart.jpg
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  • AndyGrimmAndyGrimm Posts: 910
    edited October 2015

    here my skin shader examples - showing the light color difference which is not massiv but to see - the 6500 looking more real (gen3 base texture.) - the diffrence is what i will later remove on the orignal texture...


    the third example using my new settings with BACKSCATTERING (thx to arnold - he made me understading how to use it in iray smiley).... and i think it is my best yet (comments appreciated - still trying to improve - without touching maps yet))...  subtle difference but see the nostril line - it does now shine on the edge like it should.

    all examples are done using DAZ standard and render settings - i only changed iso to 200 

     

    no-backscattering---5k spots.png
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    no-backscattering---6.5k spots.png
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    Backscattering---6.5k spots.png
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    Post edited by AndyGrimm on
  • AndyGrimmAndyGrimm Posts: 910
    edited October 2015

    Gr00vus

    Here my recommended workflow - which may help you to understand the ubershader (or shader layers in general)...AND LIGHT!

    you can use  gen3 base for this: -> You see us here talk about values and additional maps - different use of top coats and so on... this is VERY CONFUSING for a first time user.


    Important is first that you understand how a PBR shader - iray uber in our case, is organised!

    setting up a scene

    1. change NOTHING in the render settings... do not switch the HDRi map.... 
    2. pose your characater and set 2 - 4 spot or meshligths around - color to 5000k!....   i use spotlights (easier to position).. and change light geometry to a disc or rectangle (here is your meshligth with better controls)...  

    use lights with 3000 - 15000 lumens! ...... (this simulates real photo ligths in a studio with neutral colors)...
    you set the lights about 1.5 - 2.5 meters away from your model !

    if your model is still to dark -> you can bring the lights more close  - DO NOT change lumens - you let them in the range i posted above.

    still to dark -> in rendersettings change to ISO 200...... DO NOT USE or change other values!

    THIS settings above simulates SUN DAYLIGHT -> you want also use your skin shader in other light situations later.. (HDRI MAPS),,,,  that's why we use a camera with daylight values (is already there by standard).

    Start with: SCENE LIGHTS ONLY


    SKIN

    apply the ubershader.....PBR specular/glossiness

    NOW TURN OFF EVERTHING EXCEPT BASE COLOR 

    set every parameter with "weigth" to zero


    No translucency, no glossy, No top coat, No thin film...

    The only things you can see now is your base color (diffuse texture)...and bump

    Adjust the bump or normal map! -> if you show not just the face you must do this to every material surface independent! BUMP is mesh density dependent! ( that's why i use a arm and face in my tests!)....


    Render:

    ...

    base color and bump.png
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    Post edited by AndyGrimm on
  • AndyGrimmAndyGrimm Posts: 910
    edited October 2015

    next switch to DOME ONLY using our standard blue dom.... change nothing...



    If both renders looking acceptable using the SAME RENDER and CAMERA SETTINGS  you are set to start working on your shader....

    Switch back to scene only...

    base color and bump - DOM.png
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    Post edited by AndyGrimm on
  • AndyGrimmAndyGrimm Posts: 910
    edited October 2015

    NOW our goal is to add every layer and effect each step by step... 

    First ONLY translucency -> we want to come, step by step to a good skin setup...

    play around ONLY with translucency.....  set to scatter and transmitt...  and use values which are in the range arnold posted above... NO map yet...

    My gen3 looks now like this: Example one

    ( here is the reddish which we can remove later )

    your goal using translucency (and subsurface scatter) is to come as close as possible to a real looking skin allreay ( you can try SSS TINT to reduce the red - i use other ways)...

    LITTLE BIT REDISH IS OK

    If you have a "shadow catcher map" which masks BROWS and maybe other things.... you can use it here (translucency weight.

    Play with translucency WEIGHT....  you want a real skin color - litle bit reddish but not glowing or to dark (i use a dark "blood" red and a map here) -> see second example 100% translucency

    My darker translucency color - makes it to me more easy with glossy backscattering (my test series), just explaining why i ignore Arnolds adwise - it looks best weighted in with 0.45 in my case.


    EVERYTHING ELSE IS STILL SWITCHED OFF!

    If you are happy with your skin - test translucency with a BACKLIGTH (ears)....

    I use 4 lights around my model - so i can switch light and shadows (key, side, back left, back right) fast....   
    also cameras i use 3 ... so that i can watch results always from the same places - for every additional layer/effect..

    base color and bump and translucency.png
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    to much translucency.png
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    Post edited by AndyGrimm on
  • AndyGrimmAndyGrimm Posts: 910
    edited October 2015

    Translucency looking good 
    Bump too
    I think it is nice allready - little bit to warm ....  example 1

    Still everything else is switched off - NO glossy, no top coat, nothing 

    ok - for demonstration i will correct the reddish tone right now....    

    I simply reduce a little bit red in sss tint correction. example two

    base - transluceny - bump - test.png
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    sss tint correction2.jpg
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    Post edited by AndyGrimm on
  • AndyGrimmAndyGrimm Posts: 910
    edited October 2015

    ...to make it complete also the same render using just the DOM... because we started with a correct light setup.... our skin should now look good under every light condition. Here we have a colder, more diffuse light (blue DOM)...   and she looks great.

    and just a detail which is great to see now: there are strange white parts on her neck. This is light which is PAINTED in the texture.... if we aim for perfect realism such a texture will not work! that's the whole talk about Albedo Textures.... in a Albedo Map light and shadows are removed.

    However - This texture coming for free.. and is good enough for skin shader settings training  in Iray smiley...

    So - if somebody follows till here - give me a sign... because now the difficult parts start :-)

    Setting up base color, translucency,,, SSS transmitt and bump FIRST correct is the foundation for a great skin!

    sss tint correction hdri.png
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    Post edited by AndyGrimm on
  • I am following this and I really appreciate the detail you've gone into.

     

  • ErdehelErdehel Posts: 386
    edited October 2015

    I am following this and I really appreciate the detail you've gone into.

    +1

     

    Post edited by Erdehel on
  • Gr00vusGr00vus Posts: 366
    edited October 2015

    @ ArnoldC - I'm using Gimp, so I'll try to find a way to put it on a similar setting as what you're showing for photoshop (if anyone knows how to do that already, I'd be happy to hear about it). I'm taking your advice to heart, and will try to make your suggested adjustments. I did go back and redo the vibrance reduction on the base textures to more closely match yours. Again, as I'm using Gimp, the vibrance adjustment plugin there doesn't exactly match the photoshop one, so I had to guess at what MEC4D meant, with my first vibrance reduction going overboard (I used -6 on the first attempt, on the second I think -3.5 got closer to your adjusted map).

    I'll see if I can track down a shadow catcher map for the translucency strength. Not sure where to find one or how to create one, but you said there's info on it here somewhere so I'll try to locate that.

    @ Andy Grimm - I'm going to try your workflow out as well, as I like the results you're getting. Please do continue your explanation, it's very, very valuable for us who are trying to learn this.

    I'm hoping to try some of this stuff out tonight if/when I have time.

    Again, thanks to all who are sharing their knowledge, experience and lessons learned (success and failures)!

    Post edited by Gr00vus on
  • AndyGrimmAndyGrimm Posts: 910
    edited October 2015

    ok - welcome....   (i was afraid i am alonesmiley)


    ok if you master BASE TRANSLUCENCY (and VOLUME SSS) BUMP...and LIGHT...  your model renders looking great allreay... then you want add Glossines and Shine smiley

    Simplified!

    Our irayUber shader Is LIMITED (to make it more easy)... but we have 3 layers - well actually 2 and a thin film!
    our skin has way more layers..... And that's the another reason for big confusion in the forum and red glowing daz characters and readers here laugh...
    Actually - for a simplified but good looking Skinmodel... using BASE BUMP TRANSLUCENCY (sss) and GLOSSY/SPECULAR is enough...


    our goal is now to add Glossy and Specular - and we still only use BASE and VOLUME (sss)....(no top coat, no thin film)... 

    ALSO here - first you must understand how the different parameters work....

    For Fun and understanding .> use this values:

    Glossy Layered Weight : 1
    Glossy Color: 1, 1, 1
    Glossy Specular : a dark blue
    Glossiness: 1

    example 2-----   you can see that Glossy Specular is VERY important and affects the whole skin AND the Glossy color (thats why Glossy Color is ALWAYS pure white!...  you must use a REAL WORLD value here for specular.


    now change Glossy specular to 00.38 00.38 00.38... RGB 58 58 58 : example 1 -  for a normal skin with average specular use RGB 51 51 51

    real value glossy.png
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    glossy specular.png
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    Post edited by AndyGrimm on
  • Gr00vusGr00vus Posts: 366
    edited October 2015

    To partially answer my own question about creating a mask (shadow catcher) for the translucency, or, more accurately, to have ArnoldC's old post answer the question....

    http://www.daz3d.com/forums/discussion/comment/808926/#Comment_808926

     

    I got some questions about creating a "Shadow Catcher" map like those MEC4D noticed in the "Show your Iray Renders II"-Thread (http://www.daz3d.com/forums/viewreply/807952/). Since I'm not a Pro in Photoshop (mere a bloody beginner) I want to be sure I'm on the right track here. I made some screencaps for the most important stages (using Photoshop CS6).

    1. Convert the skin texture to a Black & White (greyscale) image.
    2. Remove reds by pulling the red channel slider all the way up (to 300 in that case).
    3. Apply a Gamma Correction value of 2.2
    4. Save as JPEG in ICC sRGB IEC61966-2.1 formate, as recommended in this Tutorial (http://www.computer-darkroom.com/ps10_colour/ps10_1.htm) Would have chosen .png, but sadly there's no ICC option for this.
    5. Choosing JPEG Options "Quality: 10" and "Baseline (Standard)".

    The outcome is, depending on the texture set used, a mostly white jpg. (Victoria 6's conversed textures came out almost entirely white).
    Would that be the correct procedure, or am I missing something?

    - Picking a color for the SSS "Transmission Color" :
    I choose an area of the skin texture which would be one of the brightest (in Victoria 6's case I picked an RGB of 230 - 156 - 124 on her cheek). Is that recommendable, or are there other, more accurate methods?

    - Defining "Scattering Measurement Distance":
    when applying the Iray Uber Base to V6 ("Belle" texture set), you'll get a value of 10.0. That seems to be way to high IMO.
    Using the standard value of 0.10 would also be too low I guess. Are there any recommendations, how to set this right?
    I never worked on SSS values before, I always used "what I got".

     

    MEC4D followed up with:

    http://www.daz3d.com/forums/discussion/comment/808934/#Comment_808934

    It would be better if you choice the color for Transmission by seeing the exactly level of Luminosity , what is the L in color picker
    forehead is good place to pick up the color should be not less than 56 and not greater than 72 ... around 68 is the best for Caucasian skin .
    Also regarding the shadow catcher to block the translucency from washing off the eyebrows, when you slide the red channel up , you control the level , how darker the eyebrows how better , you can remove everything else than is not white from the textures and leave only the eyebrows for ladies .. for guys would be good to leave the hair stubble too ... or scalp or body hair ...


    thanks for the illustrations it will help people to get off of the washed off eyebrows and hair


    For the SSS
    Distance : 0.50
    SSS Amount : 0.30
    SSS Direction : -0.50

    that are the best settings for me so far
    for the transmitted color choice the flash color of the diffuse

    Gr00vus said:

     

    I'll see if I can track down a shadow catcher map for the translucency strength. Not sure where to find one or how to create one, but you said there's info on it here somewhere so I'll try to locate that.

    So ArnoldC, did that method of creating the shadow capture work for the purpose of controlling the translucency?

    Post edited by Gr00vus on
  • AndyGrimmAndyGrimm Posts: 910

    How to control Glossiness...

    For fun und understanding:

    raise BUMP for the face to maximum -> example 1 shows how important realistic bump/or normal maps are! 

    a NOSE does NOT have overstanding pores! the pores are large AND FILLED.....   flat and smooth when you touch it... just a hint for texture makers  smiley..

    ok .,, ideally you would have a realistic bump map - but well i never saw one yet smiley....

    So you need a map which controls the amount of glossiness - for bodyparts which produce more sebum! and a great bump map!... no specular map is needed for human skin!...not a automatic created one! they are nonsense!

    For now we just dial back glossiness and or glossiness weight to the amount we want to see on our model (sweety, dry or whatver...)...

    fun bump.png
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  • AndyGrimmAndyGrimm Posts: 910
    edited October 2015

    Now we know -> color specularity for human skin is always 51 51 51 ( a darker grey) why do we have specularity maps? 
    If you have a map there in specualr color remove it! this is the wrong spot and just converting gen2/3 characters to the iray uber shader adds the map unfortunately in the wrong slot!

    OK, bump controls glossy -> and we can control glossiness with a map,,,

    As long as this two things are not right, it does not make any sense to layer different glossy strengths and specularity colors using additional layers! ...

    For demonstration i  reduce the bump now to zero.. and the result are very sharp glossy highligths -> i changed nothing else for this example to above.. just the bump is gone...

    glossy no bump.png
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    Post edited by AndyGrimm on
  • AndyGrimmAndyGrimm Posts: 910
    edited October 2015

    if we set glossines to 0.99 or lower... we have a additional paramater glossy anysotropy

    it does not help really for our skin glossy problem.. because there is not much of this effect on human skin...  it is also very subtle to see...

    But to make the glossy part complete..

    here 3 examples - zero bump... 

    o, 50, 100% anisotropy

    It makes the highlights softer -  i turn it on just a little bit... not sure about the numbers (Arnold?)... But because bump is way more in control of glossiness then everything else, i dont care......    i use somehwere around 0.3

    glossy no bump 1.png
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    glossy no bump 50 anisotropy.png
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    glossy no bump 100 anisotropy.png
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    Post edited by AndyGrimm on
  • Arnold CArnold C Posts: 740

    Thanks for the heads up about light colors and the colorchart, Andy. Very nice tutorial! yes

    Gr00vus said:

    To partially answer my own question about creating a mask (shadow catcher) for the translucency, or, more accurately, to have ArnoldC's old post answer the question....

    MEC4D followed up with:

    Also regarding the shadow catcher to block the translucency from washing off the eyebrows, when you slide the red channel up , you control the level , how darker the eyebrows how better , you can remove everything else than is not white from the textures and leave only the eyebrows for ladies .. for guys would be good to leave the hair stubble too ... or scalp or body hair ...

    So ArnoldC, did that method of creating the shadow capture work for the purpose of controlling the translucency?

    There it's hid itself. smiley Yes, that's correct. The "shadow catcher" (I prefer more to be named as "color catcher" or "translucency mask" for that's what it does), prevents eyebrows etc. from getting tinted by the translucency color. That's not very critical on very dark/black ones, but lighter brown or blonde ones will receive an odd redish tint.

  • AndySAndyS Posts: 1,434

    Hi,

    once again:

    Could you please give a complete summary of all iRay-parameters for the best skin setting to get the correct translucency effect without letting the skin turning too red or dark. After all the different discussion proposals I'm totally lost.

    Thank you

  • fastbike1fastbike1 Posts: 4,074

    @smftrsd72 

    You're probably lost because several people have very "definitive" instructions that ted to be fairly different from each other. I suspect partly because most of these settings are from experimentation given limited documentation, and because everyone has a different perspective about what's right. The other issue no one mentions the impact for those that are using color profiled monitors, or just montior adjustments in general.

    These could make all the difference between just right and too red/yellow/green etc.

  • AndyGrimmAndyGrimm Posts: 910
    edited October 2015

    @smftrsd72

    i did not post values for translucency and sss - because this depends of the skin texture or the character for which you try to apply irayuber. (Without altering and additional textures!)
    I tried to show that you can get great looking skins  without a lot of technical values - just using BASE MATERIAL and your own eyes and a correct light setup
    You like me to post the values i use above for THIS example - gen3 base?

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  • AndyGrimmAndyGrimm Posts: 910
    edited October 2015

    ......  the values for my examples here:..

    No additional maps - i removed them so that everybody which is still reading here can  dublicate what i show.

    I came to the conclusion that full red is not right for translucency.....   

    Translucency Color RGB: 183, 136, 100
    Transmitted Color SSS RGB: 227, 135, 68

    ALL OTHER MATERIAL LAYERS ARE NOT USED IN IRAY UBER - TURN OFF ! ....  ignore the glossiness - i am in the middle of finishing my glossy tutorial above smiley... 

    Turn off is also the problem with many posted settings screenshot.... MANY VALUES YOU SEE IN SUCH SCREENSHOT ARE NOT IN USE! and they confuse!

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  • AndyGrimmAndyGrimm Posts: 910
    edited October 2015

    this is how i decide how much transluceny weight i use....

    A light with 10000 lumen from behind about 1.5 meter away - camera daylight standard.... ears and fingers i want glowing...  neck must be on the edge... face dark!

    result 0.45.... exactly in the upper range of cauacasian people!

    When i'm finished with glossy - i test her in different lights and hdri.. and then it might be that i tweak a little bit.. but she will stay in the range of .35 - .45 i am sure about that.

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  • AndyGrimmAndyGrimm Posts: 910
    edited October 2015

    If you watch your fingers against light - test it with soft light and a very strong light! Note the difference!

    Soft light which you only see when it is dark through your fingers = red!

    Strong light which you can see also on the day = YELLOWISH ORANGE!..... that's another reason why i moved away from pure red!..

    Post edited by AndyGrimm on
  • AndyGrimmAndyGrimm Posts: 910
    edited October 2015

    Tweaking glossiness

    a real nose of  a young girl without makeup- shot with a flashlight (or mobile LED) looks like example 1:
    We can not copy the same result without a map because if we try to get this effect the glossy highlights are everywhere... example 2.... here simulating a similar situation, using camera headlamp as flashlight, no offset, strength down to 0.3- to have a similar light amount....example 2

    So - what i do is turning down glossiness to exactly a amount where a nice highlight start to shine (in this flashlight situation,.and control the sharpness/blur with glossy anysotropy...   example 3...

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  • AndyGrimmAndyGrimm Posts: 910
    edited October 2015

    and here how she looks now in the photostudio situation and also with the blue colder light dom

    edit: and one using just the standard sunsky evening.....   and 12 am

    everything with same camera values.. and zero change in tonmapping or tweaking. If i find the time i will do some using the pixar HDRi - where she even will look better...

    (i did not tweak her - to show that just minor corrections are needed - she has a little bit to much yellow now -> sss tint)

    And we can her still improve - because we have top coat as a additional material slot still empty (glossy highlight (easy map just for the nose), dirt, water splashs,  whatever you want).

    My point why i toke my time to come up with this workflow tutorial is:

    if you start with the right LIGHT setup -  and you dont let you confuse from to much values (because the ubershader has tons of slots which you DONT NEED for a simplified skin simulation. ....   you can get amazing results - the easy way smiley.

    I hope this helped some of you.

     

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  • ErdehelErdehel Posts: 386
    AndyGrimm said:


    I hope this helped some of you.
     

    It did :) Thx a lot for this comprehensive explanation of how to set skin settings in IRay. These few posts really help.

  • AndySAndyS Posts: 1,434

    Hi Andy,

    Thank you. With these values I see the effect.

    So it was not only the translucency color; the important parameter set is the transmission section. smiley

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