Daz 4.11 Iray Dark Eyes Bug ?

2

Comments

  • emu42emu42 Posts: 50
    edited August 2019

    And finally 4.12.0.67 (still looks the same as 4.12.0.60 to me):

    daz4_12_0_67_memory.jpg
    400 x 400 - 36K
    daz4_12_0_67_speed.jpg
    400 x 400 - 36K
    daz4_12_0_67_auto.jpg
    400 x 400 - 36K
    Post edited by emu42 on
  • WendyLuvsCatzWendyLuvsCatz Posts: 37,711

    is the path length set to infinite?

  • emu42emu42 Posts: 50

    is the path length set to infinite?

    It is (assuming -1 means infinite). I experimented with that parameter a bit, but ended up only with worse results or no change at all.

  • outrider42outrider42 Posts: 3,679

    EUREKA!

    I believe I have found a remedy for this nagging problem!

    So I happened to stumble across this thread yesterday. https://www.daz3d.com/forums/discussion/344276/any-remedy-for-hair-cap-artifacts

    The hair caps edges can be visible at times. The issue seems to be related to this one, the answer there was to use a morph to push the hair cap slightly away from the head. So IMO the issue looks to involve where the seams of geometry overlap a little bit, and somehow Iray is unable to properly figure out which goes on top, and as a result it simply renders this black. The eye moisture surface sits right on top of the sclera. The reason the Iris looks ok is because the cornea pushes out from the eye by default.

    So what I did was create a simple morph that pushes the eye moisture out away from the sclera. And it works! And you do not even have to push it out very far, the tiniest of distance between the two surfaces is all you need to get it to work. This might also be why some users do not see the issue, as perhaps some characters push the eye moisture out a bit on their own.

    So I would guess that this method can be used to solve some other weird instances of visible opacity seams.

    I rendered this at 12000, 0, 0. This is Genesis 8 using Genesis 3 skin (I converted to Iray.)

    Default morphs

    With my Eye Moisture Push Out morph at 100%

    So this way you can retain your eye reflections far from world center without swapping between Memory or Speed optimization.

    I uploaded one for Genesis 8 Female to ShareCG. It is an easy thing to make. I sent the developer G8F to Hexagon, selected the eye moisture surface and moved it out a bit.

    https://sharecg.com/v/94366/view/21/DAZ-Studio/Dark-Eye-Fix-From-World-Center

    You do not need to go to 100% to fix it either. Around 30-40% will work fine, maybe less depending on model.

  • TheKDTheKD Posts: 2,666

    Yeah, it's totally bizarre, getting the same results with hair and eyes in the beta. They are not even instanced items, so no idea why that setting should even have any affect on it.
     

    instnace auto.png
    800 x 800 - 636K
    instnace memory.png
    800 x 800 - 856K
    instnace speed.png
    800 x 800 - 733K
  • EUREKA!

    I believe I have found a remedy for this nagging problem!

    So I happened to stumble across this thread yesterday. https://www.daz3d.com/forums/discussion/344276/any-remedy-for-hair-cap-artifacts

    The hair caps edges can be visible at times. The issue seems to be related to this one, the answer there was to use a morph to push the hair cap slightly away from the head. So IMO the issue looks to involve where the seams of geometry overlap a little bit, and somehow Iray is unable to properly figure out which goes on top, and as a result it simply renders this black. The eye moisture surface sits right on top of the sclera. The reason the Iris looks ok is because the cornea pushes out from the eye by default.

    So what I did was create a simple morph that pushes the eye moisture out away from the sclera. And it works! And you do not even have to push it out very far, the tiniest of distance between the two surfaces is all you need to get it to work. This might also be why some users do not see the issue, as perhaps some characters push the eye moisture out a bit on their own.

    So I would guess that this method can be used to solve some other weird instances of visible opacity seams.

    I rendered this at 12000, 0, 0. This is Genesis 8 using Genesis 3 skin (I converted to Iray.)

    Default morphs

    With my Eye Moisture Push Out morph at 100%

    So this way you can retain your eye reflections far from world center without swapping between Memory or Speed optimization.

    I uploaded one for Genesis 8 Female to ShareCG. It is an easy thing to make. I sent the developer G8F to Hexagon, selected the eye moisture surface and moved it out a bit.

    https://sharecg.com/v/94366/view/21/DAZ-Studio/Dark-Eye-Fix-From-World-Center

    You do not need to go to 100% to fix it either. Around 30-40% will work fine, maybe less depending on model.

    Thank you for the morph, it was a life saver. Any chance for a male version? I've got zero idea how to go about it.

  • jstiltonjstilton Posts: 134

    thanks so much for the morph!

  • outrider42outrider42 Posts: 3,679
    I can whip one later today. I might also do G3 versions so they are out there.
  • AsariAsari Posts: 703
    That's wonderful- thx Outrider for the research and the solution!
  • outrider42outrider42 Posts: 3,679
    edited April 2020

    Ok, I got the G8M version done. Here it is. https://sharecg.com/v/95487/view/21/DAZ-Studio/Dark-Eye-Fix-from-World-Center-G8M

    HOWEVER, I want to stress that this is a last resort. You should use either memory or speed instancing optimization before ever using this morph. In fact, you should ALWAYS have one of these options selected, and I will you show you why. If you are seeing this dark eye issue, then you are having other problems with your render! This is only a band aide to mask one single aspect of this problem that Daz Studio Iray has. It is far worse than simply eyes, or even transparencies around hair. It can directly effect the color accuracy of your works, and this is a very serious problem, one that Daz needs to address ASAP. Either Daz Studio needs to fix the AUTO setting, or they need to remove it completely. It is useless. 100% useless, and it negatively effects people's works. There is absolutely no reason to EVER use auto instancing optimzation.

    If you look at my ShareCG upload, here is the 1st image.

    Here is the second. I use this as a chance to show users where the instancing optimization option is located.

    If you compare this image to the first two, you will notice that the skin is lighter in the second image. This is Sanjay 8's skin default preset, if anyone is curious. These images were rendered with the model at 2000 from the world center. However, I was able to spot a difference in the skin color even at just 500 from world center! It was subtle, but it was there. And what is important is that the eyes did not have the dark sclera issue at 500. So you would not immediately notice the problem if you were using the default auto instancing optimization. And that is terrible, because AUTO is the default! Whenever you create a fresh new scene, it is the default. You have to make sure to remember to select one of the other options every time.

    I also want to point out, if I didn't already, that you can see problems in my original pics for the female version. Look at the crack above her lip. That should not be there! Again, my morph only hides the eye problem, other problems will still be there.

    How extreme does this get? Lets look. How about 5000 from world center?

    Lets start with the dreaded AUTO.

    Holy crap, our boy became the spawn of Satan! Not only are the eyes all black, but his skin is drastically darker.

    Let's try switching to Memory mode.

    Wow, that cleared it up good. That's basically the same as he would look at world center.

    Lets try the Speed mode.

    Hmmmmm...still mildly Satanic looking. Not full hellspawn. Maybe he's just angry.

    Lets try using the Eye Moisture Push Out morph on him with the same Speed setting.

    Yay! He's not hellspawn now! But look at his skin. It is still noticeably darker than the memory mode. So using this morph only helps the eyes. If you see the dark eyes, you need to try switching this setting around, because this only masks the eyes.

    All of these images were using a single distant light, created with default settings, slight rotated to be at an angle. I also used the headlight camera at 40% strength, because I didn't want to have to reposition a light every time I moved the model. All of the positions are on the Z axis. So when I say 500 or 5000 from world center, they are all on the Z axis. This is for anyone who wants to recreate this test for themselves. I also used Sanjay's skin because I had a feeling his material preset would show off this issue better than other models.

    In this case, selecting the memory mode was a clear winner. However, it is not always the winner. I have had situations where using the speed setting worked better than the memory setting! So it is not a consistent thing, which is why I am stressing you need to try both settings. Don't just pick memory and think it will work every time. The time that speed worked better for me, I had a large scene that nearly filled my 1080ti's VRAM to capacity. You would think that using memory would be the logical choice in that situation, but no, speed was the only option that had no issues.

    So Daz staff, I urge you, this needs to be addressed. The auto option is simply broken. I believe the best course of action is to remove auto from Daz Studio until it can be fixed at a later time. The issues with speed or memory are much more palatable for users, since they work so much better than auto does. Most users will not have any idea that instancing optimization is behind this unless they happen to find this thread. So at the very least, just get rid of the option for auto. I have yet to find a single situation where auto actually makes an improvement. 

    I had a horrible time with ShareCG getting this uploaded. Seriously. It took me longer to work out ShareCG than it did for me to create the morph and the pics for it! Very frustrating. So while I promised a G3 version, its getting late and I'll do that another day. I'll probably just put them together in a single zip file so that  don't have to deal with ShareCG twice.

    Post edited by outrider42 on
  • Thank you for the fix! heart

  • outrider42outrider42 Posts: 3,679

    I tried to make a G3 version of the eye moisture pushout, but ran into some roadblocks. I also made some new observations which explain why this problem has become worse for us now.

    The first is that G3 has the eyelashes as part of the model while G8 makes the separate. I forgot that this also includes the tear that lays on the lower eyelid. On G3 this tear is part of the eye moisture surface, so pushing out the entire eye moisture also pushes this tear out as well. Its not a huge problem, but at large values it might be visible.

    Now my observations. It seems that G3 has more space between the sclera and the eye moisture. Because G3 is MUCH more resistant to this problem in my testing. In my G8 testing, I was able to get a dark eye at 2000 from world center. But G3 does not. I had to more than double that value to make G3 get the dark eyes. At around 4300 from world center it becomes visible. That is a quite a difference and really unfortunate for G8.

    So that's interesting. But the next observation is a real downer. Our modern G8 characters really hate this.

    I tried applying my favorite material G8 presets to G3. As I was not getting the eye to darken, I thought maybe something was up and changed materials to a native G3 instead. The eye was still not dark, but I noticed was something else, the skin looked fine, too. Like completely fine. Remember as I stated above, that Sanjay's skin started to look dark at only 500 from world center, and it only gets worse from there. But my G3 skin did not have this issue at all here.

    I did a lot of testing to try and see where this was coming from. What I found is that there is a relationship between chromatic sss and translucency here. If you use mono sss for your skin, the skin is largely uneffected no matter how high you turn up the translucency. I tested up to 0.9, which is as high as you would ever want to go with mono sss. Even at 10,000 from world center, I still saw no difference in the skin tone, even with auto instancing.

    However with chromatic sss I found a different story. If you keep the translucency low, the effects are not that strong. But the vast majority of chromatic sss skins I have seen have been 0.8 and higher. Many are even 0.9. When you have that high of a translucency with chromatic sss, the skin gets a lot darker as you go further from world center.

    It can be drastic.

    I tested with G3 and G8 male. I used a variation of Nix's skin on both. I tested them both with the exact same settings as well to make sure there were no additional surprises between G3 and G8 besides the eyes. There are not. So my next testing was based around mono and chromatic sss. Eventually I got to 0.9 with both at 10,000 from world center.

    This is that test, 10,000 from world center, both have 0.9 translucency. Left is mono, right is chromatic. This is with the memory setting.

    This is how they look at world center as well. So at least here, the memory setting completely erases any issues. I would post a world center test as control, but there is no point, this is what it looks like.

    HOWEVER, if you switch over to the auto setting....

    Now there is a difference. The eyes of course are effected at this distance, we already know that. But look at the skin. The mono skin is not effected at all, but the chromatic skin is clearly not right.

    One last test with speed.

    The G3 looks mostly ok. His eyes have a white ring around them, but otherwise, he's fine. But the chromatic isn't doing so well, and neither are his eyes. So once again, memory wins here. But you can see that speed can work quite well for G3 in a lot cases if you are using mono.

    So what have learned here? Well, clearly there is something about high translucency with chromatic that is a problem in Iray. Like I said, this issue is not just about dark eyes. And G3 seems to handle this issue quite well. So for people running into this issue a lot, maybe look at good old Genesis 3 for those renders, and maybe even consider using a mono sss skin set up.

    Perhaps with Genesis 9, Daz should think about how they design the eyes with this issue in mind. Just a small amount of separation between the moisture and the rest of the eye is all it takes, very tiny adjustments that no user will ever notice. And of course, remove the broken auto setting.

  • DamselDamsel Posts: 374

    What does "world center" refer to? I do a lot of romance ebook covers, and the eye bug drives me nuts. I always have to photophop it.

     

     

  • DamselDamsel Posts: 374
    edited April 2020

    Ok, I see what you mean by world center. I do renders with couples who are usually looking at each other, so that's why I always have the issue. They can't both be at world center. I'll try the memory settling. I always wondered about the hair issue, but that was easy enough to photoshop. But the eyes are a pain.

    Post edited by Damsel on
  • chris-2599934chris-2599934 Posts: 1,765
    Damsel said:

    Ok, I see what you mean by world center. I do renders with couples who are usually looking at each other, so that's why I always have the issue. They can't both be at world center.

    The problem gets worse the further you are from world centre - but doesn't really show up till you get tens or even hundreds of metres away. So providing your couples aren't practicing extreme social distancing and looking at each other from 200 metres apart, they should be OK - provided they're both near the world centre.

  • PaintboxPaintbox Posts: 1,633
    edited April 2020

    The core issue (which I read from a dev thread somewhere) is that there is a rounding error between floating values (think 0.001 values) when the subject is away from 0,0,0 (world center) and that is when you mostly get problems. This is the first time I've seen the skin reported though, very interesting to see that this can happen, so skin tone accuracy might also be affected.

    Post edited by Paintbox on
  • Paintbox said:

    The core issue (which I read from a dev thread somewhere) is that there is a rounding error between floating values (think 0.001 values) when the subject is away from 0,0,0 (world center) and that is when you mostly get problems. This is the first time I've seen the skin reported though, very interesting to see that this can happen, so skin tone accuracy might also be affected.

    The problem is, as I understand it, that the values have a fixed precision (number of significant digits). As the item moves away from th centre of the world then the gap between the start of the integer portion, specifying the distance from 0, and the later digits, recording the slightly different values for the layers of mesh, is too great for the number of significant digits and the separation gets rounded to nothing.

  • outrider42outrider42 Posts: 3,679
    edited April 2020
    Damsel said:

    What does "world center" refer to? I do a lot of romance ebook covers, and the eye bug drives me nuts. I always have to photophop it.

     

     

    Are you using the 'memory' option in the settings? I can't imagine why you would have this issue with just 2 people in an small environment with these settings. But you can also try the morphs I made if you are using G8.

    How far are your characters from the center? What is their X, Y, Z location? I think this info could help. Look at my testing, and how far my models were from the center and see how they compare.

    Maybe hardware plays some kind of role? But I really do not think that is the case. I can have 4-6 characters in a scene with an environment and between the speed and memory setting, I never have this issue. I have never actually had to resort to the morphs I created for this problem! I only created those morphs to help other people who have had it.

    Post edited by outrider42 on
  • outrider42outrider42 Posts: 3,679

    As another note, if you do use the morph to fix the issue, you can always use the spot render tool to render just the area around the eyes and drop that over the original render with dark eyes in photoshop (this is all assuming that everything in the scene is the same, including the cameras.) Because the spot render is a much smaller portion of the scene, it will render many times faster. Then it takes maybe 30-60 seconds to fix them in photoshop, most of that time is for photoshop to boot and load the pics.

    Just remember to go to the spot render tab and select 'new window', and it will work perfectly.

    This way, you do not have to render the entire scene again, saving a ton of time.

  • Hello,

    I had this issue as well. The solution I found was to go to the model's Surfaces->EyeMoisture->Specular parameters and set the Multiply Specular Through Opacity setting to On. You may need to play with other values there. I suspect this has to do with the complexity in calculating the caustic behavior of the moisture in the eye. 

    Hope this helps,

    eyemoisture_setting.jpg
    600 x 731 - 73K
    before_multiply.jpg
    800 x 800 - 164K
    after_multiply.jpg
    800 x 800 - 164K
  • Hello,

    I had this issue as well. The solution I found was to go to the model's Surfaces->EyeMoisture->Specular parameters and set the Multiply Specular Through Opacity setting to On. You may need to play with other values there. I suspect this has to do with the complexity in calculating the caustic behavior of the moisture in the eye. 

    Hope this helps,

    Just wanted to thank you for this post, it solved my issue!

  • xbartxbart Posts: 0

    Struggling with the same issue right now and for the life of me I cannot find "Multiply Specular Through Opacity" under Surfaces->EyeMoisture. Does it still exist in 4.15?

  • xbart said:

    Struggling with the same issue right now and for the life of me I cannot find "Multiply Specular Through Opacity" under Surfaces->EyeMoisture. Does it still exist in 4.15?

    Yeah same here, not seeing it annoyingly :D 

  • I am having this issue as well....again......I had it about 2 years ago and then it seemed resolved.....now it's creeping back out....I saw someone say it's linked to the hair skullcap bug when lines come through the forehead. To fix that, I always upped the scaling of the head by a percentage or 2 to eliminate that.....would that also possibly fix the eye issue?

  • outrider42outrider42 Posts: 3,679

    It would be a bandaid not a true fix, but you can move the eye moisture/cornea just a tiny bit away from the sclera and iris to make the dark eyes go away. This is not easy to do inside Daz. I made a morph that does this on sharecg linked a few posts above.

    But you should try other things first, like switching the instancing to either 'speed' or 'memory'. One of these settings is usually enough. Sometimes one works better than the other in different situations. But don't let it stay at 'auto'. You are almost guaranteed to have the issue when it is set to auto. Luckily your scene saves this setting, but any new scene you make after opening up Daz will default to auto.

  • outrider42 said:

    It would be a bandaid not a true fix, but you can move the eye moisture/cornea just a tiny bit away from the sclera and iris to make the dark eyes go away. This is not easy to do inside Daz. I made a morph that does this on sharecg linked a few posts above.

    But you should try other things first, like switching the instancing to either 'speed' or 'memory'. One of these settings is usually enough. Sometimes one works better than the other in different situations. But don't let it stay at 'auto'. You are almost guaranteed to have the issue when it is set to auto. Luckily your scene saves this setting, but any new scene you make after opening up Daz will default to auto.

    I will certainly keep an eye on this going forward.....I'm just curious why I haven't had this issue for 2yrs and now all of a sudden it came back? I can't remember if I had set anything when I first had the issue. There were a few updates between then and now. Only thing I can think if 4.15 might have changed some of the default settings? It just seems weird to me that Daz knows of this issue and keeps the culprit within the program for a surprise later on, lol. Little frustrating since I do bulk rendering....a lot of times, you don't see the issue when you use iray in the viewport, you only see it when the render actually starts. At least for me that's the case....so a little frustrating. Thank you for your help. 

  • outrider42outrider42 Posts: 3,679

    I believe this is an issue with the Iray render engine itself, and it has been around since Iray began. The problem is that Daz added a new default option for instancing that is auto, and auto is completely and totally broken. If you haven't updated Iray in a while, your old version may not have had this auto preset. So really, this is both Nvidia and Daz's fault. Nvidia never truly fixed it, and Daz has only agitated the situation with an extremely poor design choice that does not work. Daz has the ability to remove the 'auto' option, it is their software.

    Another thing that may be happening is unintentional design choices by PAs that make this glitch show up. As we get more complicated material setups and shaders...you are bound to get more complications as a result. You might not see this issue with some shader setups. As my tests above show, chromatic sss can have its own issues away from world center besides just the dark eyes.

    Just curious, can you say what specific character you are using? It could be the way the character was made. You could look at the surface settings for eye moisture and cornea and see if they are different from the characters who do not have this issue. You could probably just copy the surface settings from the working characters to the ones with the issue. That might solve it if this is a material setup thing. There are several things that can contribute to this problem. You have geometry, the instances, and the materials.

  • That would be difficult to do because all of the characters I work with are created by me. Only 2 that I use are straight up models from the site. It doesn't happen on every character though. I have only seen it effect 3 out of all the models that I use. I'm able to fix the issue in photoshop if I don't catch so it's no biggie....just time spent later on....though, rather not spend that extra time.

  • outrider42outrider42 Posts: 3,679

    In that case you can still narrow this down. Do your characters use the same eye materials? If not, then maybe the ones effected have a different value and you can change it. The other option is if your morphs are effecting the eyes. That is probably the case, your morph effects the eye just enough to cause this issue. And in that situation, pushing the eye moisture out (like my morph) will very likely fix it. The distance you need to do this is extremely small, so small you may not even be able to see the movement of the moisture in your modeling app.

    I made my own, but all I did was jump into Hexagon, highlight the eye moisture, and move it slightly on the Z axis. This doesn't work as easily with Genesis 3, because of the tear being part of the moisture. You could also shape the eye itself instead, pushing the effected area a hair back from the moisture. But that would be much trickier to do.

  • I have this issue in 4.15, I tried all the suggestions on dark botches, black sclera, etc. Changing geometry, poses, depth for rays, etc.

     

    The only thing that has ever fixed this for me has been to center the character to 0,0,0 on all the axis and move the environment around the character 

Sign In or Register to comment.