Interior lit by HDRI DomeLight - am I insane?

[fewlo]

Hello all,

Is it ridiculous to think you can light an interior, with fairly small window openings, just with an HDRI on a domelight? I work with 32bit EXR, Linear colour mapping LWF, then do post in after effects, . Here's what always happens:

- add domelight with Peter Guthrie HDRI
- start optimizing using Akins theory
- add domelight into the equation and get massively frustrated that I can't get clean reuslts from the domelight, even with extremely long render times
- end up reverting to storing with irradiance map for domelight
- output to 32bit exr and heavily comp in After Effects
- get great feedback from clients but left feeling dissillusioned as an artist that I'm just not getting something right at base level!

I'll lay myself bare here with a before/after still from a typcial animation:



Its all a bit flat I think due to the light being stored, but as mentioned if not stored the noise is unacceptable from the dome light. Also I always fight against burn out, especially when there is only 1 small window like in a bedroom.

Any thoughts on what I'm doing wrong or is this all to be expected?

[peterguthrie]

Hi Michael,

If you can send me the scene I'll happily take a look at it (assuming i can find time!)

Peter

[fewlo]

Hi Peter,

That would be great if you have a minute (or two!), I'll provide a scene, not particularly this one, but certainly one that highlights my ongoing problem...

[peterguthrie]

send it through. peter@peterguthrie.net

[eyepiz]

Please post your finding...I have the same problem with interiors looking a bit flat.

[Morbid Angel]

well, its not uncommon to do artistic lighting when staging photography in interiors/exteriors. So, perhaps this is something worth exploring. If you guys would like, I can also take a look

[Dariusz Makowski (Dadal)]

A world of advice. The images you look at from photographers. Most of the time there is LOTS of retouching with quite a bit extra of artificial lighting. Start playing with lights would be my suggestion and learn retouching :- )

[samuel_bubat]

Honestly it´s pretty much nonsense lighting an interior with a HDRI. There are many points that speak against it.
1. Most HDRI have a way to low dynamic range to get a strong enough direct from the sun within the HDR.
2. If you examine a daylight HDR than you´ll notice that usually just the sun has values above 1. So basically
you can just replace it by a direct or a vray sun wich offers you after all, the same effect with a lot more options
like color, intensity, shadow softness.
3. Don´t worry about your reflections. If you use strong lights and strong environments again like a VraySun/Sky
or direkt/environments with values above 1. Your scene itself becomes HDR and reflecting objects inside the interior
receive nice strong reflections from the windows.
4. Keep in mind that a HDRI makes a diffuse lighting. So getting direct light with nice shadows from a Sunny Day
requires enormous ranges wich I haven´t found i a single HDR we bought over the years.
Check out the free Paul Debevec HDR´s. Those make nice direct like shadows. But they have ranges way above 1000.
You can probabely wait till the end of time until they generate an absolute clean result
4. If I look at your images and the light coming through the windows it could be just replaced by a single environment color
and the effect would be pretty much the same.

I would use HDR´s only when you match objects into a photo of a complex lighting situation. It´s perfect for exteriors
like rendering a car into a backplate, or some object into the photo of a room, or basically anything where you integrate
3D into real scenes. But for lighting an interior. it´s just giving away control of your lighting without a real benfit.

[fewlo]

thanks guys, so Samuel and Dadal, you do think I'm insane to light an interior by HDRI?

I've seen some wonderful imagery and animations by BBBViz and I'm sure he only had the one peter guthrie lightsource... so it must be possible ha!

I often have 30 different animation shots making up one house tour and naturally it is more economical - timewise- to have almost the same lighting throughout, clients usually want to see a correct sun position also. So a lot of the rooms in a typical house don't have direct light from the sun, just the subtle environment lighting of the HDRI, which I like tbh. Are you suggesting that each clip would be much better lit independently, which would in turn lead to quicker light calcs and lower subdivs etc?

[Dariusz Makowski (Dadal)]

I would use sun for direct sun and GI source.

I would use a humh... calm HDR - no strong light sources. Just ambient light. To fill in the gi with light portals OR just rely on GI. I think you could precalculate GI very quickly and just use gi for lighting this way.

As long as IBL dont have light sources then you will get soft realistic fill light in your houses that should render relatively quick.

[Morbid Angel]

thanks guys, so Samuel and Dadal, you do think I'm insane to light an interior by HDRI?

I've seen some wonderful imagery and animations by BBBViz and I'm sure he only had the one peter guthrie lightsource... so it must be possible ha!

I often have 30 different animation shots making up one house tour and naturally it is more economical - timewise- to have almost the same lighting throughout, clients usually want to see a correct sun position also. So a lot of the rooms in a typical house don't have direct light from the sun, just the subtle environment lighting of the HDRI, which I like tbh. Are you suggesting that each clip would be much better lit independently, which would in turn lead to quicker light calcs and lower subdivs etc?

I think there is a misconception about use of hdr/its purpose. Hdr is used imo to place 3d obj in to a photographic environment, so to approximate the lighting correctly from otherwise impossible sources of the photograph.

however, when you have full cg environment (your rooms) and ext image has little lighting coverage, you need not use hdr at all, just colors from portals.

[Pixelcon]

I do think HDRs aren't the easiest thing to work with when lighting and interior but some lighting schemes just can't be achieved with the vray sun/sky. Some of PG's HDRs with low golden sun really look great for interiors. If you are however lighting the interior with indirect light and/or small openings you could use an HDR as a "look development" tool before replicating the light colour/GI colour with the vray sun/sky for speed.

[Dariusz Makowski (Dadal)]

I always use blurred IBL for GI pass. Just so much better than a vrays sky to get all those variations and so on.

[eyepiz]

I always end up brightening my scenes in post...this weekend I watch a YouTube video from Paul Fatkins (Basic int Lighting with Vray and 3DS max) . I was surprised to see he used a box with a mesh light covering almost the entire interior of the scene to create ambient lighting...looks like it worked well.

I am interested in exploring this approach has anyone used this method before?

https://www.youtube.com/watch?v=5j_-GDFQIts

[squintnic]

there are many ways to skin cats
i see bros getting caught up with trying to replicate other peoples work and forgetting to experiment.