No detail in shadows.

[dandelO]

That's great advice Martin. I only wish I could use it like you do! I often use double atmos, like you say but still, GI in those atmos is never practical for me...

It kind of defeats my purpose of messing about with secondary lighting. My only reason for doing this is to conserve on render times, since GI takes up very much of that time, I look for solutions of getting around that, as I use a pretty poor machine for rendering(2x2ghz). I tend not to exacerbate GI calculations in rendering, which is what adding multiple atmos would do to me when rendering with GI.
If I could, I'd use GI consistently but I have to cut corners. So, messing around with other lighting solutions seems to be my only option, for now.

Of course, if computer power and render times are not of any consequence to you, as they are to me, you'll get great results using GI consistently, and by using TU's techniques up there. ^^ Go for it!

[Tangled-Universe]

I see your point Martin, although I really think you over-estimate the added rendertime by having two atmospheres in the type of setup I described.
I would have to do decent benchmarks to verify this, but I think I can safely say that it will at most add ~20% rendertime.
An advantage is that in many scenes, without dense vegetation for example, a GI setting of 1/1/8 will be sufficient.
So if only 20% extra rendertime is required, it still would be faster than upping the GI settings by 1.

Everybody should realize of course that this should all be evaluated for every single scene. I mean lighting, GI, rendersettings etc.
So even with my method above there's no absolute golden standard which will always give the best results.

[treddie]

Tangled-Universe >  That is an awesome image you posted and I can see your points, and I want to experiment with your ideas.  But in that very image...the trunk and branches of the big tree in the back have essentially gone to black with no detail *at least from what I can see in the small image).  This simply would not happen in reality.  That is why I keep pushing the importance of at least mid-range GI (which you used) but in the case of that tree, I think it begs for more, despite a higher rendering time.

[dandelO]

Aye, I get that, Martin. Still, GI in atmosphere takes aprox' double the time to calculate over an edited lighting setup that I would use.
When a basic GI pass takes so long for me, adding secondary atmos will not make it any quicker, if you see what I mean.
This is just my experience, of course. I'm not down-playing your techniques by any means. Everyone can see your lighting solutions are always superb when you render! I'm just a humble cost-cutter.

Oh! For a new computer!

Cheers, man!

* Treddie: I can see all the detail in the tree you mention in TU's scene, there are no blacked out areas for me viewing it here, it looks lovely, as I posted to Martin on another site where he posted the full size image. It's a beautiful lighting setup he has used.

[Tangled-Universe]

Tangled-Universe >  That is an awesome image you posted and I can see your points, and I want to experiment with your ideas.  But in that very image...the trunk and branches of the big tree in the back have essentially gone to black with no detail *at least from what I can see in the small image).  This simply would not happen in reality.  That is why I keep pushing the importance of at least mid-range GI (which you used) but in the case of that tree, I think it begs for more, despite a higher rendering time.

I cropped the image using html code to make the post more readable. Here you can find the full-res:
http://fc02.deviantart.net/fs70/f/2010/228/a/b/Overcast_Weather__V2_by_Tangled_Universe.jpg

As you can see the drop-off isn't that bad at all.
You won't get this much GI/light when using "conventional" tweaking of the GI settings.
Even with GI settings at 4/4/8 or higher you will not get that result.
The numbers of GI-bounces TG2 utilizes is just too limited, so you need to help TG2 a bit by adding lots of diffuse light.

[Tangled-Universe]

Aye, I get that, Martin. Still, GI in atmosphere takes aprox' double the time to calculate over an edited lighting setup that I would use.
When a basic GI pass takes so long for me, adding secondary atmos will not make it any quicker, if you see what I mean.
This is just my experience, of course. I'm not down-playing your techniques by any means. Everyone can see your lighting solutions are always superb when you render! I'm just a humble cost-cutter.

Oh! For a new computer!

Cheers, man!

* Treddie: I can see all the detail in the tree you mention in TU's scene, there are no blacked out areas for me viewing it here, it looks lovely, as I posted to Martin on another site where he posted the full size image. It's a beautiful lighting setup he has used.

Oh this is good discussion Martin Sharing ideas and solutions is what we all love here, at least we do for sure

Here's a comparison which I made very quickly (see below).

1) = default atmo only @ 17s
2) = default atmo + overcast atmo (no disabling of any rays) @ 26s
3) = default atmo + overcast atmo with primary disabled @ 19s
4) = default atmo with secondary disabled + overcast atmo with primary disabled @ 17s

As you can see the added rendertime isn't much at all. Perhaps not very scientific in regard to render-resolution and detail, but you can see that it renders relatively very fast compared to having 2 fully functional atmosphere-nodes at one time (2 vs the rest). So in a more serious situation you will not have to expect a huge increase.
Second, if you look carefully, you'll see that with 2 fully functional atmosphere nodes there's a lot more noise. So what you can basically conclude is that the number of samples required for a clean result is determined by the primary rays (compare 2 with 3 + 4).
So you could conclude that it is also render-inexpensive.

[treddie]

Tangled-Universe > That image is killer.  It's fun to move around and check out all the little spaces.

But I think the big tree trunk though is just too much of a silhouette still.  Everything else has great fill in the shadow areas.  Compositionally I like it because it makes the tree the first read, and your eye moves on from there.  But in terms of how light behaves, if GI can't get in there, what would you do?  Put a big reflector in there that is not visible to the camera, so that you can affect that region only, without disturbing everything else?

[dandelO]

Good comparison chart, Martin!
I think that No.4 looks so much better than TG defaults, and for the same render time, that's great.

People should really exploit these settings, I know I do. Remember, you are not limited to one atmosphere node/lighting solution/planet/etc. Mixing and matching multiple nodes is a great way to combine many different aspects of light and atmospheric effects. The 'primary/secondary' checkboxes in your atmospheric shaders are your friend and a really cool tool to use for scene effects. Maybe you like the rays that a certain atmosphere node creates but you hate the sky/haze colours, no problem! Enable only primary in your 'sky colour atmo' and only secondary in your 'effects atmo' and you can mix and match both. The combinations are endless. Experiment!

Great thread, with lots of hidden gems, once again!

[Tangled-Universe]

Tangled-Universe > That image is killer.  It's fun to move around and check out all the little spaces.

But I think the big tree trunk though is just too much of a silhouette still.  Everything else has great fill in the shadow areas.  Compositionally I like it because it makes the tree the first read, and your eye moves on from there.  But in terms of how light behaves, if GI can't get in there, what would you do?  Put a big reflector in there that is not visible to the camera, so that you can affect that region only, without disturbing everything else?

Well technically there should be some silhouetting, still, because the sun is positioned behind the tree just at the left outside the image.

But regardless that I think you expect way too much. This is TG2 and not Vray, Maxwell or whatever
The GI and all the tricks available here is very suitable for procedural displacements.
The rendering of objects is not equally developed in that regard.
This is the trade-off in the engine I think. Vray, Maxwell and the other raytraced renderers available are 100% sure not able to do what TG2 does.
What they can do though, is render objects beautifully and accurately (user-dependant of course), something TG2 is less well at.

So if you're looking for a way to get the result you're after then I think I will have to disappoint you?

Martin

[treddie]

Oh, not necessarily.  Just trying to push TG2 to its limits.  I've done a lot of experimenting with Maxwell and it is a fine renderer, but like you say it's just a renderer.  I feel that if TG2 is behind in that respect it isn't by much.  One thing is for sure...realism is expensive both financially and work-flow wise.  If you rely heavily on refractive materials, complex displacement or even worse, SSS, the only solution I see is a small render farm.  I'm running a quad-core hyperthread with 12Gb of RAM and to do high resolution justice and do it in a reasonable time frame I would really need about 3 of those MINIMUM.  It boggles the mind sometimes.  Reminds me of running Sculpt 3D on an Amiga back in the late 80s..."OH come ON already...Huuurrrryyyy UP!" 

[AP]

Not really. Check out Modo. Bloody fast renderer using heavy sets of shaders/micro poly displacement and ray tracing with GI, even on my old P4.

[treddie]

A friend of mine back in L.A. loves Modo.  I've never tried it out, but he swears by it.

But nothing rules over TG2 for the most absolutely stunning atmospheric effects.  Even to this day I can't help but be amazed.

[dandelO]

I was amazed when I trialled Modo. The GI passes are extremely fast. I remember wishing that TG was going to get that sort of speed up someday, no luck on that front yet, though!

[treddie]

It's coming I'm sure.  The one thing I REALLY like about Planetside is that they don't make over-ambitious claims and then disappoint.  They are patient, methodical and quality oriented.  If they can't guarantee something by a certain date, they don't even go there...it's done when it gets done right.  That's my impression anyway.