Light up an interior scene with HDRi

[AdamT]

It's possible, but not really practical as you would have to use a huge number of samples and a very high diffuse depth.

[SecretDesign]

I'm trying to get a good scene done with GI and a few lights, but the render time is to much now. Need a render time under 30 minutes. Now its a little under an hour.

I use 3 lights, omni with area shadow (know that area shadow is slow.) The radiosity setting is set to a low setting.

What should I use for shadow instead of area shadow and still get the same effect?

[dtoxxx]

Have you ever worked with HDRI lighting before?

Because those spheres you speak of are the actual lighting for the scene.
They have to be just images on a sphere to properly light the scene, and provide true reflections.

You CAN adapt this to indoor lighting it just might take a little work.
You'll most likely have to use some compositing tags for your objects in order to keep the shadows and illumination right.

And probably some diffuse trickery with a somewhat higher sample rate, but I wouldn't say it's not possible or totally impractical.

I think I could do it if I had to.

[dtoxxx]

Yeah that's kind of a toughie.
Using GI, but having to keep the render time under 30mins is a tough one.

Is this an animation?
Have you heard of the problem with GI flickering during animation?

The only thing I can suggest is Ambient Occlusion.
Less render times, but it's not a real GI solution.
Not sure how it stands up during animation.

[the-negative]

Personally I would just skip to hi-res (read: RAM) soft shadows instead of hard and render Ambient Occlusion as an external pass. Shadow hardness would differ that much.

[SecretDesign]

yes its an animation. I need the rendering to be as good as possible. But if I need to have rendretimes up to an hour per frame then so be it. Have heard about GI flickering during animation, but some say its not there and others say that is as bad as hell..

Ambient Occlusion, havn't used it before. Any good tutorials on how to use this?

[dann_stubbs]

yes its an animation. I need the rendering to be as good as possible. But if I need to have rendretimes up to an hour per frame then so be it. Have heard about GI flickering during animation, but some say its not there and others say that is as bad as hell..

Ambient Occlusion, havn't used it before. Any good tutorials on how to use this?


on a single CPU it is relatively easy to get rid of GI flicker.

on a render farm or multiple CPU it is very difficult (or time expensive) to get rid of GI flicker.

AO can be almost as long as GI in render times, but no flicker.

dann

[SecretDesign]

Sounds very strange that you can't use GI in animation because it causes flicker. Why would they (Maxon) have such a big fault in the render?

[makind1]

yes its an animation. I need the rendering to be as good as possible. But if I need to have rendretimes up to an hour per frame then so be it. Have heard about GI flickering during animation, but some say its not there and others say that is as bad as hell..

Ambient Occlusion, havn't used it before. Any good tutorials on how to use this?

if you are doing animation, what about using GI Baking
Bake your textures to the walls.

[dann_stubbs]

Sounds very strange that you can't use GI in animation because it causes flicker. Why would they (Maxon) have such a big fault in the render?

nearly every GI solution - with can have flicker - some of the newest are just finding ways around it. mental ray flickers the same or worse.

essentially GI was a still image thing - with the ever increasing horsepower it can now be used for animations with patience. it was only a couple years ago that GI and CPU's became a possibility for animations. bluesky's bunny was the first "big" short film to use GI which helped bring it to the attention to many and they used their own renderer.

dann

[dann_stubbs]

nearly every GI solution - with can have flicker - some of the newest are just finding ways around it. mental ray flickers the same or worse.

essentially GI was a still image thing - with the ever increasing horsepower it can now be used for animations with patience. it was only a couple years ago that GI and CPU's became a possibility for animations. bluesky's bunny was the first "big" short film to use GI which helped bring it to the attention to many and they used their own renderer.

dann

and to be fair to maxon and AR - steve bell (don't know website offhand) has done some very nice animations using GI and just lots of power and patience.

dann

[SecretDesign]

Ok, what would you have to do to get rid of GI flicker?
Edit every frame in photoshop?

Need to test this out to see how bad it is. Have just made an animation using Fprime and lightwave with radiosity without any flicker so quess this must be one of those renders that doesn't have flicker?

[leed]

It is about optimizing the scene. Normally I use area shadows at the beginning, because they look good over a distance but they are the first to go when animating.
Do you have diffused reflections?... they can hit hard on the time....What are your GI settings?

Post a test pic with your settings. lets have a look and see. Every image is different. it may help get your times down.

About the animation though, do you have time to render on 1 computer, if you get your times down?
If so then use camera animation. As long as there is nothing else moving in the scene.... that should work.

Lee

[SecretDesign]

It is about optimizing the scene. Normally I use area shadows at the beginning, because they look good over a distance but they are the first to go when animating.
Do you have diffused reflections?... they can hit hard on the time....What are your GI settings?

Diffused reflections? Where do I find that?

About the animation though, do you have time to render on 1 computer, if you get your times down?
If so then use camera animation. As long as there is nothing else moving in the scene.... that should work.


No, must render it on a render farm. But if the render times gets down to well under 30 minutes it might be enough time to render on one computer with dual core.
There are a couple of doors that are opening but other then that it's only the camera that are moving.

I'll post up my settings and a test render later tonight.

[leed]

Diffused reflections? Where do I find that?



It is called Dispersion, in the Reflection of the Material editor, if you are cutting back that set it to 0%,
There is a lot about GI optimization on this forum, but in the past I have opted for non GI animation with specific colour AO, applied to specific materials within the scene, put 2 -3 soft shadows omnis in with resolution at 40%, with a bright shadow casting light.

GI across a farm is difficult.

Lee

[acid2002]

Hi

There is a very good tutorial here.

http://www.meltinglight.com/pages/BasicHTML.html


Derek

[AdamT]

One way around flicking is to bake your GI solution, but if you have a lot of moving objects (as opposed to moving cameras) you'll have to work around that.

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