Iray lighting bugs! Is my Daz Studio broken?
Rafa20
Posts: 92
I'm struggling with this problem since 3 whole days and just can't solve it!!! I've really tried everything!
I have a very huge scene with a lot of props and environment (a hallway with lights, furniture, other rooms in the hallway etc.). Also a background with houses, trees and an IR-Base from this product https://www.daz3d.com/iray-worlds-skydome (I'm using just the IR Base without the skydome and sun.)
I've created a primitive sphere and took an emissive uber shader on it to simulate scattered day light from outside coming through the window (with soft shadows). I've tried it also with a photometric sphere/disc but these things are always visible in the render (Nevermind if "Render Emitter" is ON or OFF!!!) .
Here the weird issue: If the scene is complete then it looks like this:
https://s5.postimg.org/ou3nvn65z/1_Whole_Scene.jpg
It's darker and the character looks like in a comic!!!
But if I delete everything around but this bedroom (and its props) with the character, the sphere mesh light outside and the IR Base, then it looks like this:
https://s5.postimg.org/annx0faqf/2_Only_Bedroom.jpg
It's brighter and the character looks normal!
I absolutely don't know what's causing this! I've tried to delete every little prop step by step and thought many times that I found the prop which is causing this lighting issue. But after loading this whole scene again and deleting this prop it was still the same cartoon style! Only if everything around is deleted, then the scene (light) looks natural!
Does anyone have a clue or idea what's the matter of this ridiculousness here??? I really don't know what else I could try and I'm startin' to get really desperate! And I urgently need every prop around!
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Comments
You're deleting (or including) items that block light. I don't know what your scene is or what all the props are, but part of that is obvious from what's happening with the door area. Note on the floor that the color of the light on the floor changes when you've deleted the hallway outside the door, and that area is a little brighter. That's because the HDR you're using is no longer being blocked by the hallway itself.
From the way the light changes, it looks like there may be something outside the window in the darker image that's blocking the light or casting shade. When you delete everything around the room, whatever is blocking the light isn't there any more.
Since it's meant to be an interior scene and you have lights on in the hallway, for this scene to work the way you want, you need to have lamps or an overhead light or something that would create light within the room. Otherwise, the darker scene looks perfectly reasonable for what it is: a room that's not getting a lot of sunlight where it's dark enough that you have inside lights on anyway.
You might be able to get more light into the scene by turning up the intensity of the HDR, but without knowing what's casting the shade or how the scene is structured, I can't say for certain.
Why do you need the IR Base for an interior scene where you can't see it?
I need the IR Base because this is just one image out of 40 of this scene, where you can see the IR base out of the window.
And even after deleting the whole hallway with all the lights and props it looks still the same: https://s5.postimg.org/cn4irt2h3/3_Deleted_Hallway.jpg
And I don't need more light! I've created an emissive sphere with a cutout of 0.0001 and positioned it in front of the window. And the light is perfect in the second picture with everything deleted around. I don't want any electric light in this room cause it's day and I want only the simulated scattered day light from outside. I also don't want a spotlight because of the harsh shadows!
I've found out that one reason for this was a pole light from outside which I forgot to turn off. But nevertheless it looks a little better now it is still "comic like".
Now to get the normal light rate like in Picture 2 (Only Bedroom) it works only this way: you have to delete all lighs of the hallway and delete the entire hallway. If you delete only the hallway lights... it doens't work. If you delete only the hallway... it doesn't work. Only if you delete the hallway + the lights (and maybe some more props) so that there's only the bedroom with the character left. Only then you get the proper light rate! WTF??? Can someone explain this? Actually I think this is either a Daz Studio bug or the scene is damaged somehow!
In fact, it doesn't look the same. Look at all three images side-by-side-by-side. You've got three different lighting situations, and they all look different. In terms of lighting, Deleted Hallway is between Only Bedroom and Whole Scene; "Deleted Hallway" is more blue because of the sunlight and blue sky, and it's somewhat brighter than "Whole Scene" as well, but not as bright as "Only Bedroom". Somehow, some way, there's something in the scene outside the window or around the room that's affecting things. I can't know what that is, unfortunately.
If "Only Bedroom" contains the lighting you want to show up in the scene, and "Whole Scene" is the way you want the part outside the doorway to look, the simplest solution is to render it twice -- which you've already done -- then layer them together in your graphics program -- Photoshop or GIMP or whatever -- then in the "Only Bedroom" part of the render, delete/erase the scene through the doorway so that IR Base is gone and you can see the hallway. That way, you can have things look exactly the way you want. Beyond that, I think you're kind of stuck with what you have. Until you can figure out what's affecting your lighting in the scene, it's simply not going to be possible to make it look the way you want otherwise.
(Edited because I realized that I'd said exactly the opposite of what I meant at the beginning. Sorry for any confusion.)
Probably (... possibly) not relevant to your inquiry, but I'm curious and also a bit confused. Are you using IR Base purely for the ground plane? If you've deleted the skydome that comes with IR Base and its lighting, where does the sky in the background of "Only Bedroom" and "Deleted Scene" come from?
OK but how can the closed lights of the hallway and all the props around the bedroom influence the light coming thought the window in the bedroom and the surface of the character? That's nonsense! There's nothing in front of the window except the invisible emissive sphere. I also got some weird bugs while using the Iray preview. Sometimes when I delete things and the return them back they are invisible. I don't know but maybe I have to reinstall the program again. I think I worked over 10k hours with Daz Studio now but I never had such an annoying issue!
Well, thanks for your help attempt. I guess I really have to render it twice like I also thought myself before. The only problem is the light on the floor which comes from the hallway. If I delete everything but the bedroom I will have a completely different light as with the hallway!
I'm looking at the "whole scene" and "deleted hallway", and swapping back and forth between the tabs. I'm not sure what you mean by the whole scene looking like a comic, but the main difference I am seeing between the two is that the whole scene is a lot grainier. It looks like there are lights in the hallway, so the scene is more complex both in geometry and lighting. Is the "whole scene" rendering for a longer time than the one with the hallway deleted? If they are both reaching a set time limit (I think by default the render settings have a limit of two hours on a render), you may want to raise the time limit on the whole scene to let it render longer and see if the shadows smooth out to what you expect.
If the issue is with the overall scene brightness, if you haven't already you may want to adjust the tone mapping. Since it is an interior scene, with diffuse light coming from the window and doorway, you may get results you want by adjusting this. I am not very experienced with this, but SickleYield has a short write up on it that can help: https://sickleyield.deviantart.com/journal/Tutorial-Lighting-and-Tone-Mapping-In-Iray-531864617
What are you expecting? I'm not seeing anything look off really; the light changes in those two scenes as one should expect.
The one with only bedroom has more blue because there is more blue light.
The right of the image, looks like it might be a window? Is there glass in the window or just space? If you can remove the glass do so, it might make lighting it easier, and it might not.
Lighting is possibly the toughest aspect of 3D rendering (and photography too I believe).
Not nonsense at all, light reflects and bounces; there look to be lots of glossy surfaces in the images, which will create lots of bounce. Have you converted the items to IRAY shaders, or let IRAY do it. And what conversion have you done if you have. Selecting everything and just using the Uber shader doesn't do a bad job, but the more complex the scene, the more issues.
It has nothing to do with tone mapping or render time or everything else that has been mentioned here. The thing is: I have a huge scene in which I'm changing a few things what has a drastic effect on the light coming through the window. In front of the window is nothing but an emissive sphere which is invisible (cutout 0.0001)!
I already found two things in the scene which are causing this issue. The first one are the brightly burning pole lights outside. And the second is the IR-Base where I had to turn the luminence off and put the emissive color on "none". Pay attention on the glossy parts of the skin of the guy on the bed.
Here are 3 complete render examples where you can exactly see the difference and what I mean!
1) The very first render. Very little light is coming through the window. Look at the surface of the guy on the bed. He looks so strange as if he's painted! His glossy parts on the skin are dark!
https://s5.postimg.org/d6iss9iuf/Day11-2_2_Sophia_enters_Dylans_room.png
2) In this render I turned the pole light off outside and also turned off the luminance of the IR-Base and put the emissive color to "none". Everything looks much more natural and also the guy has a more realistic skin surface. But the glossy parts are still not 100% natural!
https://s5.postimg.org/s2hbzvhef/Day11-2_2_Sophia_enters_Dylans_room2.png
3) In this render (I rendered it briefer than the other two!) I deleted everything but the bedroom with the guy (and the woman). The skin and the lights look even more natural than the render before. The glossy skin parts are perfect and natural!
https://s5.postimg.org/ivz1ceh93/Day11-2_2_Sophia_enters_Dylans_room3.png
But I absolutely don't know, what influences this difference between render 2 and 3! I only get this greatest light rate when I delete the hallway lights and the hallway with all the props. So, how can this influence the light coming through the window and the character's skin? I don't delete anything behind the window! Only the hallway and its lights which are in the back! And the weirdest thing is: only when I delete both the hallway and the lights I get the result of render no. 3.
From what you've shown, it looks like there is geometry of some sort blocking the environment light from coming in the window (this is of course assuming you haven't changed tone mapping). The second image being brighter than the first would indicate that geometry associated with the "pole lights" outside the window are blocking light from entering the window (they must also not be extremely bright, since the image is lighter with them gone ... what are the lumen values for them??). My guess on the third Image is that there is some geometry associated with the hall that is blocking some of the environment light. Make a new camera, and move it to where you can see everything that is outside your room (zoom way back to insure there isn't something unexpected in the background blocking it), I'm guessing you will see something that is partially blocking the environment light from getting in the room (keep in mind that sometimes what seems logical to you, may not be the same logic used by the creator, so there may be "stuff" that you think shouldn't be blocking light that is blocking light). If this is the case, and the geometry is tied to something you want in the scene, then just use a sectional plane to "hide" the offending geometry from blocking the environmental lighting. It may also be possible that the window pane is a part of what is being hidden, and it is causing some light to be locked (even though it is transparent).
What I tried is to delete every light in the hall except of one. I also deleted the most of the hallway. And here if I turn the last light off then the light which comes through the widnow changes too. How is this possible? How can a simple single mesh light plane in the hallway influence the whole scene? But attention! Also only if enough parts of the hallway are deleted. If I don't do this then also the lights don't change anything.
In your complete scene you have 3 lights that affect the bedroom: the emissive sphere at the window, the lamp post and the IR base. The only way for any of these lights to get into the bedroom is through the window, but there is the sphere in the way (even though it is set to almost completely transparent, it's not completely and therefore defuses the other lights passing through it.)
You mentioned lights in the hallway, but I suspect they might not be giving off enough light to bounce enough through the doorway and around the rom to brighten it up.
So when you remove said hallway, all the light that it was blocking (the lamp post and the IR) can now come flooding in through the doorway as well as the window (although still difused a little bit from the sphere)
That mesh plane will possible interract with light rays; I seem to recall that mesh lights do that, but can't be sure.
Test. Set the mesh light to be very low, it should be just visible in the scene.
Put a bright light behind it from the camera's perspective; is there shadow cast by the light plane due to the other brighter light?
I use ghost lights if I want to boost the light coming in through windows, doors, and holes in general (be there glass there or not).
On reading all of the posts in the thread, my first thought was also that something must be blocking your light from outside. I did just have a thought, even though it's an outside chance - what setting do you have for the camera headlamp? If it is set to "Auto", it could be increasing or reducing light to the scene in different situations. It might be worth checking and setting it to "off" to see if it makes a difference.
You say it happens when you delete all the props and leave the room on its own? It looks like you are getting the light from the HDRI, which you can see through the door, which is now coming through the window where before it was being blocked by geometry.
I would delete the emissive sphere, and instead place a flat plane ghost light (ie: an almost invisible primitive, like your sphere) next to the window, but just inside the room. This will boost the light but still look like it is coming from the window, so should not significantly change the look you are after. This should render faster than you light set up. The enviromental light coming from outside should still be there, and will help to provide specular light that makes the scene look less toonish, the ghost light at the window simply boosts the light in order to speed up the render. If the scene looks to dark, increase the tone mapping.
Thanks for your answers! Actually most of that I already tried myself.
@Havos For this scene I just seperate them and cut them together in PS. But from now on (the next interior scenes) I think I'll try the ghost light. I never did it before because I thought it's the same like an invisible mesh light plane! But maybe it's really different from it...
Interior scenes with no direct lighting are always a challenge for Iray or any other PBR engine. What you need are ghost lights to fake some direct lighting into the scene. Then you can use tone mapping to tone down the image as needed. Remember that even real cameras have issues with dark scenes. In cinema and TV movies tone mapping techniques are often used in post to convert a daylight scene to a night scene. With PBR engines you have similar limitations.
https://www.daz3d.com/iray-ghost-light-kit-2
I've experienced strange changes to the overall lighting in scenes when adding emissive planes a couple of times. The first time it happened, I had the scene mostly lit, but needed to add another small emissive plane to fill an area that was a little too dark. After adding the extra light, I did another test render, and the lighting was totally messed up - like the main lights on the character had been turned way down.
Long story short, after messing around for ages trying to correct it, I found that switching off the extra fill plane restored the original lighting. Turn it back on and the lighting was messed up again. The plane wasn't blocking anything, it had a cutout opacity of 0.0000001. In the end I gave up trying to figure it out and just hid all the scenery and props and every light that didn't affect the main character, and rendered the character alone, then hid the character and his lights and rendered the scenery on its own, then merged them in post.
The concept is the same as your sphere, however a plane primitive is just one light source (ie 1 polygon), so quicker than the many polygons of a sphere, also if the light is inside the room it does not have to consider refraction from the glass planes which would make a tiny difference to your render, but does slow down the calculations of the paths from the ghost light.
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Next scene and again such issues! Especially the more I tried to edit this scene the worse the lighting got! I think my Daz Studio is broken!
In this kitchen scene there are three ghost lights right behind the three windows and one on the ceiling.
And here the strange thing. Every light outside of the kitchen is making the scene darker! Outside is a backyard with a pool. Inside the pool there are pool lights on both sides. If I turn these lights on, the scene gets a little brighter. Even the luminence of 1 makes the scene darker. Then if I put the environment intensity on 0 the scene gets again much brighter! WTF???!!!
1) Original Scene
https://s5.postimg.org/54aut2c0n/1_Original_scene.jpg
2) Pool lights turned off (at surface tab)
https://s5.postimg.org/jnhzuhcvb/2_Pool_lights_turned_off.jpg
3) Pool lights turned off + Environment Intensitiy on 0
https://s5.postimg.org/mucje4cqv/3_Pool_lights_Environment_Intensity_on_Zero.jpg
Does anyone have an explanation for that? I'm working since 1,5 years with Daz Studio (over 10k hours experience!) and this issue appeared the first time with the scene at the beginning of this thread (1 week ago)! I never had such issues before!
The only thing I can think of is to uninstall and reinstall the program. But before I'll do that maybe someone has another idea. Maybe I accidently turned some option on somewhere which has to be turned off...
EDIT: After updating the program to the newest version my Iray preview is blinking blue and pink now. I can't imagine this is normal! I uninstalled Daz Studio with the Install Manager and installed it again but nothing changed.
https://s5.postimg.org/s71ds8sxj/image.jpg
https://s5.postimg.org/wg63uhgs7/image.jpg
Is your camera Headlamp on auto?
That is the only reason I can think of that would make the scene brighter if lights are removed, because it will switch on automatically when the light is too dim. However if this was the case your scene would get much brighter, which is not what you are seeing.
Also what do you mean by the pool light enviroment intensity? Normally enviroment intensity is a render setting affecting the HDR or sun-sky brightness, not settings of individual light(s).
My camera lights are always off.
Inside the pool are round pool lights on both sides which you can turn off at the surface tab by putting the luminance on zero. And yes, additionally I also put the environment intensity on zero at the rendering settings tab. So, if you turn all those lighting off the scene gets brighter and brighter what is very odd! Like I said. I'm working since over 10k hours with Daz Studio and never had this problem before.
But look how my Iray preview looks now after updating Daz Studio.
https://s5.postimg.org/s71ds8sxj/image.jpg
https://s5.postimg.org/wg63uhgs7/image.jpg
I'm very sure that Daz Studio itself is the problem. So, that's why I think of reinstalling it properly.
It is odd, particularly since the light alteration is so small, however I have noticed the brightness change when I swap from Render mode "Dome And Scene" to "Scene Only", and I think sometimes the light increases (though mostly it decreases). Although you have not changed the Enviroment Mode, when you set the Environment Intensity to 0, then you are effectively saying "Scene Only".
You can try reinstalling, but I would be surprised if that changes the behaviour you are seeing.
OK I tried to power uninstall and reinstall the program by deleting everything. And yes, it didn't help!
The problem with uninstalling Daz Studio is also that it never uninstalls it properly. You have to reinstall windows so that it is deleted completely.
I absolutely don't know how it is possible that if you put the environment intensity on zero the interior scene gets brighter and more lights comes through the window. And if you increase the environment intensity then to the contrary it gets darker and less lights come through the window (don't forget I got the ghost lights behind the windows).
What is additionally very odd: There is a light plane in another room which is closed by walls and doors. So, no direct contact to the kitchen. But if I delete this light plane then also less light come through the window into the kitchen.
Emissive plane is turned on (behind the wall) = more lights come through window.
https://s5.postimg.org/mpddi4hxz/Plane_ON.jpg
Emissive plane is turned off (behind the wall) = less lights come through window.
https://s5.postimg.org/ejvbk21fr/Plane_OFF.jpg
Is there really nobody out there who has an idea of this whole oddness??? Is the whole scene maybe broken? Or my program?
If I was going to guess; the problem is not due to a broken Daz Studio but the construction of your scene. Since you are using a closed building in a skydome, you have a box within a box.... As a rule, a skydome will be slower than a HDRI with more diffuse light and a performance hit. With the closed building, any light that comes in is through a transparency which becomes a second performance hit. Next you add lots of props and characters who need their reflections and everything calculated thus a third performance hit. Since you have a limited amount of iterations to render your scene in, you get fireflies. When you delete stuff, less calculations and scenes get clearer, brighter, and less cartoon like as you have more interations for your render. There may also be some interference between lights in the props and lights in the scene.
I would try 1) remove any geometry that isn't being used, 2) use the Iray light portal to make your windows more efficient, (https://www.daz3d.com/forums/discussion/113636/do-iray-light-portals-work-in-ds4-8) 3) hide every ceiling or wall etc... if it isn't in the scene, and 4) the iray plabe could be your friend (https://youtu.be/GCJfIlk-4Yo).
The lights look to be working correctly here.
Picture 2 Pool lights off -- the light on the picture and the girls back is lost so they darken because of the loss of light from the right.
Picture 3 pool lights with dome zero -- you are now getting the light back from the right but have lost the ambient light frrom the dome so shadows on the left of things are darker.
Picture 4 plane on -- is giving fill light from the left giving a highlight down the left side of the kitchen towel roll on the table and is brightening the shadow on the fridge door so acting as a fill light softening shadows.
Pictures 5/6 --- by turning the plane off the fill light from the left has gone but it also looks like you turned the pool lights off too as you have lost their light from the right.
If you open all the images on separate tabs and flick back and forth from one to the other you can see the shadows and highlights change as each light is turned off or on.
Maybe if you post some wireframe shots of the scene surroundings we could have an idea of what is going on.
Looking at your last two screenshots... how does it look in the actual render, rather than the viewport? Is this primarily an issue with the preview?