Vray Domelight and HDRI - HDRI not showing in viewport and render

[Guest ksymenaborczynska]

I'm flollowing the tutorial by Peter Guthrie on HDRI lighting, seem to have all the camera and render settings set correctly and still - i can't figure out what I do wrong.

 

I have a HDRI map set as texture in my domelight (not selected as "invisible" or anything like that). The map doesn't show in the viewport (when I select "Use Environment Background", the viewport turns all black) and in the render there is no background whatsoever.

 

I use 3ds max 2013 and V-ray 2.4.

 

Attached is everything that can possibly help to spot what's wrong.

 

I would be very thankful for any advices, I'm struggling with what seems to be so simple for quite a time and it's rather frustrating. How is it that what's shown as achieved so effortlessly causes such problems to many people?

Edited April 29, 2014 by ksymenaborczynska

[RyderSK]

VrayDome light doesn't show in viewport, it's not considered "environment" to 3dsMax (which refers to Environment slot in ExposureTab from rendering pulldown menu). So the viewport is black because that is the default color of unmapped Environment slot.

 

If you want such preview, instance the same map from material editor to both environment and domelight slot (requires latest SP5 update from 3dsMax to work correctly).

 

I suppose it doesn't show in viewport from this angle only, since Peter's HDRis are hemispherical with black part bellow horizon.

 

I also think (but do that many people stuggle?) it cause confusion because the idea of domelight instead of directly sampling Environment slot is weird at best.

[Guest ksymenaborczynska]

Render setup.

[Guest ksymenaborczynska]

Thank you for your quick and very useful reply.

I've been trying to use HDRI with domelight, as that's what most of the tutorials recommend, strangely, and avoided the simple way.

As it turns out, you're right - with your simple and clear answer, as always.

[RyderSK]

Well, Vray has two ways to sample HDRi for direct light (better noise and GI convergence, so it should be used):

 

a: VrayDomeLight ( you can still use the environment slot for preview, but keep the DomeLight ON) for exteriors, or interiors with 'large' windows.

b: HDRi in 3dsMaxEnvironment slot and VrayLight set to SkyPortal at windows: for every other interior, it samples faster

c: HDRi in VrayEnvironment slot in Render settings/Vray rollout and VrayLight set to SkyPortal at windows, same as above

 

No combination of Domelight + SkyPortals.

[Guest ksymenaborczynska]

Thank you once more. I'll experiment with those settings and let's hope the results will be satisfying,

[paneli]

No combination of Domelight + SkyPortals.

 

I actually never tried Sky Portals, but why not combining?

[moifa]

Hi Juraj,

 

I also would like to know why "No combination of Domelight+SkyPortals". Most of the tutorials out there use that method, including me. Is there a reason for it?

 

Also may be you could help me to solve this as well. My HDRI image is showing up as bands in the viewport and it render fine. I lower the Overall Mult to a level where I can see the image probably in the preview (not white). I also turn up the viewport texture to 4k but it doesn't fix it.

 

Thanks.

 

[padre.ayuso]

I actually never tried Sky Portals, but why not combining?

 

So it intrigued me. So I tried it myself. The result, the rendering is smoother, less noisy, less lit as well, but it seems more realistic, light is not bouncing unrealistically all over your scene. I increased the HDRI mult because it was darker compared to having it on the dome light, and the space is now better lit, more realistic. I had done a similar scene earlier with domelight and skyportarls and they sucked, I ended up with fireflies and noise everywhere. Anyhow, that's what I have experimented so far. Anyone else can input their test results.

[yp]

Even though this thread is a little older I have to jump in here, a little confused..

 

I did not use VrayHDRIs in the environment slot before much because it always caused more grain / noise.

Strange enough I was surprised by the speed and quality an HDRI, plugged into the environment slot, produced with an interior (I do exteriors mostly). Preview / LQ renders turn out pretty slick actually.

 

The light intensity of the HDRI is lower, true, but as I tend to stick to real light values and corresponding physical camera settings it wouldn't matter much to me tweaking the HDRI values - as those are kind of "unsure" anyways.

 

I ran into some strangeness now - rising the HDRI value does work up to a certain degree only - rising it higher does not bring brighter results!

Same with camera: brightening up the image through ISO, FNumber or Shutterspeed gets kind of "clamped" as well -> concearning the HDRI only. Other light work fine, same as the HDRI in a dome light.

 

Tried it with various HDRIs and several setting, all the same.

 

Maybe I'm missing something?

 

To get noise free results like a simple quick render with HDRI in environment slot I have to crank up the quality quite high, no matter if I use HDRI only or HDRI in the environment slot along with light portals (set to normal, simple work only for simple, small openings with no things in front of the window or overhangs and such).

 

See images, hope they explain things a little further.

Those images were rendered all with the same physical camera settings.

Images with lit with domelight or portals on are very grainy compared to the environment slot only.

Brightness is more or less not controllable with HDRI in environment slot only (for interor, exterior is different, strangely)

 

Different camera settings. Lower exposure is possible.

Higher exposure gets "clipped".

(Pendant lamp light is off in the second image, image would be too overbright otherwise)

 

Edited October 30, 2015 by yp

[RyderSK]

HDRi (or any texture) in Environment slot alone, is not considered a "light" in Vray, unlike other renderers. It looks most smooth, because it's not importance sampled, so it's sampling rather convoluted clamped version of the texture. If you look closer, you will also see it provides incredibly poor GI quality when used with conventional IR/LC method.

 

My chart still applies, it's good to almost always simply use Domelight (only). Direct light and GI will get sampled correctly, and the noise can be treated like should in Vray3.2 , using sampler threshold.

[yp]

Juraj,

 

thanks for clarifying. I was expecting something alike, kind of no GI calculation as the render looked flat. Stupid me I chose a dull /overcast HDRI for testing purpose - with a clear sky it would have been more visible (and obvious..).

Using a HDRI (or just an LDR image) in environment slot and setting up a direct light / vray sun in the light position like the sIBL method from HDR Labs (if I'm not mistaken now) would be a quick render workaround with better results but as for not as good as the direct HDRI calculation with a domelight as you describe.

 

Actually I had some trouble with getting the threshold low enough to get rid of any visible noise even though there are big openings. Finally used the "store with IR map option" to blur the lights. I had some troubles a while ago using this option for a domelight which took me some time to indentify the cause so I was kinda reserved using this option.. will use it for sure if it turns out working properly.

 

Any thoughts about that? Appropriate use to eliminate noise?

 

BTW: For interiors with SMALL openings I'd refer to your post #5, HDRI in vray / max environment and light portals (set to normal if there's "something" outside) and NO domelight - it calculates more GI samples inside and therefor creating less noise. Right?

 

Thanks, as usual, for your insights!

[RyderSK]

The sIBL method, convolutes HDRi to supple importance sampling, but Vray (and other renderers) already do this by default :- ) If you place 14 000px HDRi into Vray domelight, it will only sample light using 512px (default, or otherwise as specified) version. So no need to go all old-school and create 3 version of same map as sIBL :- ). The idea is correct and right, just not neccessary anymore in most renderers.

 

Regarding using HDRi with clamped or no direct light (like overcast), or LDR in environment, and using direct light/sun/other analytical light,

that will work, because the directlight/sun will be able to sample directly but of course, in interior spaces, where lot of light is still coming from environment, the GI wouldn't work well anyway, so the environment, would need portal lights, which effectively become analytical lights with intensity of environment. So the interior will sample those portal, not the texture behind them in environment.

[yp]

Yeah,

 

I'm catching up and will arrive in present soon. Just digged out the "HDR vs sIBL" thread some hours ago.

I really like those tech talk things, especially those bright aha-moments.

 

Setting up a diffuse lighting (equals VrayHDRI in env in this case) + direct light works in exterior, did gain a speed saving of roughly a fifth in a quick test scene - but the quality in direct comparison was lower (less diverse). Seemed like that, but it was a rough test only, might be interesting to crunch rendertimes for animation. Didn't look to close into noise differences there.

 

For the skylight portals mystery, my basic understanding of GI in this case is, that the number of rays traced inside of an interior without portals (and small openings) is just too low and therefor creating noisy / blotchy renders - and light portals are substituting that calculation with additional rays, right? In my actual interior scene there are some quite big openings (but with large overhangs in front) and the render is a little too noisy in HQ settings. With "store with IR map on" its way better interpolated (and quicker), but only really HQ settings are more-or-less free from blotches. Any way to get more rays traced with simple domelight only?

[RyderSK]

Domelight shouldn't produce splotches unless you're using "Store with IR" option, which I would stay away from, always. Even for animations, where every second counts, I rather simplified my lighting setup than go with "Store" because the interpolation (which you then have to substitute by higher IR settings) simply sacrifices visual quality of shadows far too much.

 

Usually portal lights do what you describe, facilitate rays towards where they point, although I am not sure if that's exactly how they work in Vray (although they definitely function like that in every other renderer). I rather believe (but here I am not sure...) that they simply become area lights of light intensity behind them. Which seems kind of similar, but it is also the reason why they affect lighting solution slightly (or more in "simple" mode).

 

The best sampling solution overall is this:

 

[djordjemiletic]

ive got problem with black render. Using vrayphisical cam and dome light...when i use domecam there is a normal render..but somethings wrong with phisicalcam and render is black...can u help ?

[djordjemiletic]

im using vray physicalcam and dome light with HDRI texture..but render is black? when i use domecam render is not black.So i suppose there must be some problem with physical cam?

[yp]

Djordje,

 

why domecam?

 

What exactly is black? Background? Full render?

Vray version?

 

If background is black - maybe "invisible" in domelight options is checked?

Depending on the file you're saving the background may appear as black as well.

 

If the problem still exists, post back.

If the question has been solved a short feedback will be nice, too.

[djordjemiletic]

All render was black..vray adv.3.00.07..i merged my objects with camera in new scene and the problem was solved..i still don't know the real reason of the problem.invisible was disabled, it wasnt a problem..