Cool Vue 7.5 Image

[Jack]

ambient occlusion with the right settings mixed with global illumination and a second dim sun backlight along with the main sun at brighter settings can pull of global Radiosity effects wish we did have a proper global radiosity as the one in vue really brings out the detail

[Tangled-Universe]

ambient occlusion with the right settings mixed with global illumination and a second dim sun backlight along with the main sun at brighter settings can pull of global Radiosity effects wish we did have a proper global radiosity as the one in vue really brings out the detail

http://forums.planetside.co.uk/index.php?topic=6581.msg70027#msg70027

Martin,

As to my other question, how long did it take you to setup this scene and render it? TIA -Chipp

Sorry, I think I missed your other question, however...I can't remember exactly.
From my head it took about 30 hours to render at 1080p resolution with pretty insane settings.
Setting up the scene from scratch, exclusive tinkering with TG bugs, was about 2 to max 3 working days I think.

I presume you'll reply you can do it faster with Vue

Martin

[Seth]

exclusive tinkering with TG bugs


Martin

huhu

[PG]

He could do that in Vue by pressing the New button

[chippwalters]

I presume you'll reply you can do it faster with Vue

Not my point at all. I was just wondering. I've had Vue renders which take significant time to complete with not so hot results, so I'm in no position to throw stones at such an exquisite render.

best, Chipp

[Jack]

I presume you'll reply you can do it faster with Vue

Not my point at all. I was just wondering. I've had Vue renders which take significant time to complete with not so hot results, so I'm in no position to throw stones at such an exquisite render.

best, Chipp

I don't think chipp is here to bash terragen I think he is just curious about are renders and how they where made

[Tangled-Universe]

I presume you'll reply you can do it faster with Vue

Not my point at all. I was just wondering. I've had Vue renders which take significant time to complete with not so hot results, so I'm in no position to throw stones at such an exquisite render.

best, Chipp

I don't think chipp is here to bash terragen I think he is just curious about are renders and how they where made

I too thought that wasn't chipps intention

Thanks for the compliments chipp The image's thread can be found here:
http://forums.planetside.co.uk/index.php?topic=5981.msg64223#msg64223

Oops...what did I see there? It rendered in >20 hours...not ~30

[Matt]

Vue is very different w/regard to GI vs Radiosity. You can see an example here. I believe Radiosity is a superset of GI. In anycase, I don't know how TG interprets either.

Hi Chipp,

Vue and Terragen use the term "global illumination" to mean different things, so it's not always obvious how to compare them directly. In Vue, "Global Radiosity" is a more realistic solution than "Global Illumination", but that's just a Vue thing. It may be an unfortunate side effetc of their introducing their better global illumination (which they called radiosity) after they had already released a simpler solution called global illumination (I may be wrong about the reasons though). In Terragen, Global Illumination is analogous to Vue's Global Radiosity (as I understand it). Global Illumination in Terragen tries to account for diffuse interreflections, specular interreflections (with limited quality), as well as light from luminous/glowing/emitting surfaces and atmosphere and clouds. Also, the clouds and atmosphere react to global illumination just like surfaces do (I think Spectral Atmospheres 2 has this now too).

So when we say Global Illumination in Terragen we're talking about a solution that tries to account for *any* kind of secondary light in the scene. No exceptions (unless you count inaccuracies or level-of-detail simplifications). In Vue, I think this happens with their "Global Radiosity", but they are using the term 'radiosity' incorrectly. In CG research, 'radiosity' is an old algorithm which was developed a long time ago to simulate diffuse interreflections only. Global Illumination is a more general term for all lighting contributions which are not coming from direct light sources (to put it informally). So Radiosity is a subset of Global Illumination in the wider CG community. In Vue it's just become a bit confused because of the terminology.

http://en.wikipedia.org/wiki/Radiosity_(3D_computer_graphics)
http://en.wikipedia.org/wiki/Global_illumination

The radiosity article i linked to above is not to describe how Vue does it, because I believe Vue uses a Monte Carlo solution which is (or can be) more general than radiosity.

Matt

[Matt]

ambient occlusion with the right settings mixed with global illumination and a second dim sun backlight along with the main sun at brighter settings can pull of global Radiosity effects wish we did have a proper global radiosity as the one in vue really brings out the detail

In TG2, Ambient Occlusion is just a simplified version of Global Illumination that does not look at the colour of the surrounding environment, it only calculates the shadows, and you have to decide what colour and intensity to use. Global Illumination should give the most realistic results. Adding a second Ambient Occlusion light just adds more 'fake' light that really shouldn't be there. Sometimes this looks better because it allows you to simulate more skylight without making the sky brighter, which might be a way to deal with the huge contrast between sky and landscape, but I wouldn't say it's more photorealistic. OTOH, because fine shadow details are difficult to catch - without GI surface details which is SLOW! - there might be some useful contrast boost within the shadows if you use Ambient Occlusion, but it's not really supposed to work that way.

Matt

[Matt]

If shadows are too dark with Global Illumination in TG2, the first thing I will always suggest to try is increasing the camera's exposure. There's even a widget for it in the 3D Preview as of v2.0 because I think it's a much overlooked setting.

Matt

[Tangled-Universe]

If shadows are too dark with Global Illumination in TG2, the first thing I will always suggest to try is increasing the camera's exposure. There's even a widget for it in the 3D Preview as of v2.0 because I think it's a much overlooked setting.

Matt

Thanks for the extensive info in your previous 3 posts Matt.

Increasing the exposure is a good solution for lighting up your shadows, but aren't you also increase your directly lit surfaces as well? (probably not directly proportional?) I think that isn't really desired always?

I still think it would be nice to have a setting similar to 0.9's "shadow lightness".
However, I must say that rendering with GI @ ~2/4 gives very nice results, though a tad slow, but still the best bang for bucks imo.

[rcallicotte]

Thanks Matt.  This understanding you've given is directly helping me on an image I'm working on now.

[Matt]

Thanks for the extensive info in your previous 3 posts Matt.

Increasing the exposure is a good solution for lighting up your shadows, but aren't you also increase your directly lit surfaces as well? (probably not directly proportional?) I think that isn't really desired always?

Yes, it brightens everything, but if you want to brighten up only the shadows it usually looks unrealistic to me. Raising the exposure maintains the correct balance between sunlight and shadow which the GI has calculated for you. I really like that look of super bright highlights when you want to expose things for the shadows. Having said that, with low GI settings it may not be lighting things up quite as much as it should, so this is only a guideline.

Photographers sometimes use bounce cards or fill lights, but that usually looks unnatural to me. I prefer a realistic balance between sunlight and shadow that's motivated by the rest of the scene. But shortcomings of the GI system at low quality settings may influence how you want to change the lighting.

I still think it would be nice to have a setting similar to 0.9's "shadow lightness".

You can increase the GI contribution above 1. It's not 'correct', but it may do what you want, or it may be justified by a lack of accuracy at low GI settings. If you want complete control over the shadow colour and shadow lightness as in v0.9, just use Ambient Occlusion mode and then you can set whatever light levels you want. That's pretty close to what you did in v0.9.

Matt

[scott8933]

I've been amazed at what you can do just by rendering out to a format like EXR - seems like you can bash on the exposure endlessly and still keep the image from blowing out or banding.

If shadows are too dark with Global Illumination in TG2, the first thing I will always suggest to try is increasing the camera's exposure. There's even a widget for it in the 3D Preview as of v2.0 because I think it's a much overlooked setting.

Matt

[efflux]

Agree totally with scott8933.

Since we are actually often trying to emulate photos then we need to use similar techniques. Sky is often very bright compared to ground.

This is one render where I kind of experimented with adjusting sky and ground separately from exr. I think I actually rendered the atmosphere separately to use as a blend between two different exposures (exr adjustments) but I want to try different methods of blending the two exposures. Looking through my work, this image has some nice qualities of space and light that the others don't have. Also, I think TG2 shadows from atmosphere are often too dark. Many lightly overcast days are still quite evenly lit with no major shadowing. Ground may be much darker but not totally shadowed.

http://forums.planetside.co.uk/index.php?action=dlattach;topic=5579.0;attach=14537;image