Iray renders completely BLACK - 4.8 Beta

Occams_Razor

Hi All,

Running into a peculiar problem with IRay rendering in the 4.8 BETA.

I loaded the scene from Stonemason's Winter Kingdom: Castle Ruins.

(http://www.daz3d.com/catalog/product/view/id/13049)

Made no changes to anything in the scene.

Went to the Render tab and selected NVidia IRay as the Engine.

Click on the "Default" button to make sure nothing I have done before, (goofing around with other renders), would carry over.

Click on "Render".

I see message that Iray is compiling 0/134 shaders, (which I didn't change or alter).

Why 0/134? LuxRender actually shows it as compiling and showing count of each shader before it starts rendering.

See "Rendering image"

"Rendering..."

IRay Iteration: 1
IRay Iteration: 2
IRay Iteration: 3
...
IRay Iteration: 28
99.98 image converged...
IRay Iteration: 30

Render completes and I have a completely BLACK render image window. Actually not completely Black. It does appear that there is 1 point of light in the render but that is it.

So....

What might I be doing wrong? I don't know enough to really troubleshoot since I haven't changed anything! Trying to learn so any help would be appreciated.

BTW Renders in Basic OpenGL, Intermediate OpenGL, 3Delight and LuxRender, (via Luxus) all render just fine. LuxRender takes forever to actually show anything but it does, eventually, show an image.

:(

SickleYield

What graphics card are you using? Rendering black sometimes happens when you've checked the graphics card but Iray can't use it (because it doesn't have enough memory, usually, but some models are just not inherently driver supported, especially on laptops).

Occams_Razor

SickleYield said:

What graphics card are you using? Rendering black sometimes happens when you've checked the graphics card but Iray can't use it (because it doesn't have enough memory, usually, but some models are just not inherently driver supported, especially on laptops).

I do not have any GPU selected. Just the CPU. I am ashamed to say that the graphics card is just the integrated Intel HD2000 that this Gateway machine is saddled with currently. I am currently looking at updating said card, (probably to a GTX 750 TI), but for now that is what I got. Probably doesn't help that this box also only has an Intel Core i3-2120...

:P

FirstBastion

If you left everything "default", I think that winter set has a skydome, and that would probably stop the unbiased light from hitting the scene.

Occams_Razor

FirstBastion said:

If you left everything "default", I think that winter set has a skydome, and that would probably stop the unbiased light from hitting the scene.

Okay... I think.

I don't know what I don't know yet so...

How do I avoid this issue?

Set Draw Dome = Off?

Change Dome Mode to ??

Thanks!

Richard Haseltine

The dome setting in Render Settings are for the Iray "virtual" sktydome. The one that's in Winter Kingdoms is a real dome, textured with the sky. You can delete it, replacing it with the iray SunSky or with an HDRI map applied to the Iray Dome, or you can select the surface of the dome with the Surface Selection Tool and then in Shaders>Iray in Smart Content apply the Emissive preset and set Iray to render with Scene lights only (since the dome and the sun/sky will be blocked by the dome prop).

evilded777

Go to your Scene tab, and find wkTerra1 and expand it; you will then see wkSkyDome. Either delete the skydome or hide it (not sure if hiding it will work, but it might).

grinch2901

OcamRzr, iRay uses physically based lights, that is to say "real world". So if you put something between the light and the thing you are rendering, it is in shadow and if the thing in between is big enough, no light at all will get through. So if it;s an interior set and totally enclosed and you are using the render setting "Sun-Sky" then the sunlight would not get through the exterior walls without a window somewhere (just like the real world.

Similarly a dome would stop any sunlight from coming through but in iRay your camera has a "headlamp" attached to it and unless you specifically turn it off, it's on and casting light so I don't know why you wouldnt be seeing that. If you are seeing a small bit of light it's possible that some lights loaded with the set and confused the renderer. DAZ Studio native lights don't work with iray, you have to use the new iRay specific lights or the Sun-Sky render setting.

You don't say you added any light but worth mentioning that if/when you do iRay native lights come in with ridiculously low settings, like the equivalent of the brightness of a digital watch trying to illuminate a big dark cave. The default lumens is like 1500. You have to crank that waaaay up, tens of thousands of lumens. 20,000 or even 30,000 is pretty common and for some scenes people are in the millions. So maybe you have a light and it's just set to the default (which is almost the same as not having a light)?

evilded777

grinch2901 said:

OcamRzr, iRay uses physically based lights, that is to say "real world". So if you put something between the light and the thing you are rendering, it is in shadow and if the thing in between is big enough, no light at all will get through. So if it;s an interior set and totally enclosed and you are using the render setting "Sun-Sky" then the sunlight would not get through the exterior walls without a window somewhere (just like the real world.

Similarly a dome would stop any sunlight from coming through but in iRay your camera has a "headlamp" attached to it and unless you specifically turn it off, it's on and casting light so I don't know why you wouldnt be seeing that. If you are seeing a small bit of light it's possible that some lights loaded with the set and confused the renderer. DAZ Studio native lights don't work with iray, you have to use the new iRay specific lights or the Sun-Sky render setting.

You don't say you added any light but worth mentioning that if/when you do iRay native lights come in with ridiculously low settings, like the equivalent of the brightness of a digital watch trying to illuminate a big dark cave. The default lumens is like 1500. You have to crank that waaaay up, tens of thousands of lumens. 20,000 or even 30,000 is pretty common and for some scenes people are in the millions. So maybe you have a light and it's just set to the default (which is almost the same as not having a light)?

One does not need to increase lights to physically improbable levels if you correctly implement Tone Mapping. Adjust your camera and your lights as appropriate.

Stonemason

since Winter Kingdom uses custom shaders made with shader mixer I don't think iray would support it,it's designed for use with the 3delight engine only,

mjc1016

Stonemason said:

since Winter Kingdom uses custom shaders made with shader mixer I don't think iray would support it,it's designed for use with the 3delight engine only,

That's the procedural snow, right?

No, that probably won't work for Iray...and then it's got the 'atmosphere' cameras, too. They can be reproduced with Iray versions, but the snow would be very hard to duplicate.

It would probably look pretty good without snow, but just won't be Winter Kingdom...

Occams_Razor

Stonemason said:

since Winter Kingdom uses custom shaders made with shader mixer I don't think iray would support it,it's designed for use with the 3delight engine only,

Though I have been able to get a somewhat decent render playing around with IRay you are absolutely correct that you can only see the true beauty of the background when it is rendered with 3Delight.

Leave it to me to find the one background scene that doesn't play nice with IRay to try and learn this new engine.

:P

Occams_Razor

Richard Haseltine said:

The dome setting in Render Settings are for the Iray "virtual" sktydome. The one that's in Winter Kingdoms is a real dome, textured with the sky. You can delete it, replacing it with the iray SunSky or with an HDRI map applied to the Iray Dome, or you can select the surface of the dome with the Surface Selection Tool and then in Shaders>Iray in Smart Content apply the Emissive preset and set Iray to render with Scene lights only (since the dome and the sun/sky will be blocked by the dome prop).

I tried using the Emissive preset and it worked! But.... Made the background way too yellow. Played around a bit and found that changing the K value of the Sun helped get me the right color but it was still too dark. I am sure that someone with more experience could make it work but as Stonemason chimed in and noted you lose a lot of detail when trying to force it to render with IRay since many of the shaders are custom made in the Shadermixer and don't translate well, (if at all), in IRay

Here are 2 renders of everything exactly the same except for the changes I made to get it to work in Iray.

1st is 3Delight. 2nd is Iray.

emclean2014

dim pushed an update through the other day for 4.8, and since then ALL my renders in iray and 3d delight are coming out black and nothing i have tried is fixing it. previously fin projects rendered in both engines now only produce black, completely black as if nothing is even there to render black, screens, has THIS happened to anyone else?

BeeMKay

Nve you tried uninstalling, re-downloading and re-installing this set: "Default Lights and Shaders for DAZ Studio 4.8+"?
It's part of 4.8, but a separete download. It's possible that the 4.8 update flattened the light install, and now the default lights don't work.

emclean2014

lee_lhs said:

Nve you tried uninstalling, re-downloading and re-installing this set: "Default Lights and Shaders for DAZ Studio 4.8+"?
It's part of 4.8, but a separete download. It's possible that the 4.8 update flattened the light install, and now the default lights don't work.

no wouldn't have thought i would have had to. i will give it a shot and see if that fixes it. thanks.

on the flipside, i did go to do this and found that 4 parts of 4.8+ auto uninstalled all on their own and were sitting in dim waiting for me to install them again for the 2nd time. so anyone else having this issue, look there first, might be a simple fix.