I've rendered two images of exactly the same tgd file; only changed the image width and -height in the Full Render settings: one image 320x240, the other: 640x480 pixels. Both renders look completely different in colour, texturing and lighting. eh... ???
Attached I sent the concerning tgd-files, the WorldMachine Heightfield I used and the two rendered images. Checked and rechecked the tgd-files, but they look exactly the same. Maybe I overlooked something... ???
I've seen this before. In an another situation, which is closely related to this, I rendered an entire picture of 2400X1440 and then went back to render only smaller cropped areas. Interestingly, the cropped areas were more defined, tighter in color, and seemingly denser as a whole than the larger 2400X1440 picture. I believe I read once that Matt explained this as having to do with how GI is calculated...or it might have had something to do with the scope of the render.
I'm sure someone else might be able to explain this better.
For GI calculations, TG2 doesn't consider areas outside the actual render quad. So when you use crop, the lighting situation will be different then if you render the whole image.
I guess EmDee1s problem is similar and that the accuracy of GI rises with image size.
Thanks Calico and Nikita for your replies. Still hope there will be more said about the subject...
At this very moment I feel a bit confused and frustrated, feeling that this amazing TG2 Landscape render-engine (still the best in its domain in my opinion), leaves me with a great uncertainty. Why use crop renders, why use smaller renders as a preview, as the final render result can differ considerable from what one might expect?
I was able to manipulate my crop renders with Photoshop to readily fit within the original scene.
TG2 *does* consider areas outside the crop/render area for GI, but it has to do so at a lower detail level than the main render for reasons of time. This can result in inconstencies like those described here. The GI system will be improved over time, but for now it may be best in these situations to simply use a fill light setup such as the one provided in the File Sharing area here: http://forums.planetside.co.uk/index.php?topic=580.0
GI accuracy is also relative to detail level (hence the setting name "GI Relative Detail"). So if you have this set to 2 and detail at 0.5, if you then increase detail to 1.0 and leave Relative Detail at 2, the lighting can change because the GI detail has actually increased with the overall increase in render detail. Again these consistency issues will be worked on but inevitably with any GI solution you are going to see differences at varying levels of detail. If the inconsistency is a significant issue a well-tuned fill light setup ought to give you reasonably similar results with more consistent output.
- Oshyan
Thanks; I'm gonna study the suggested fill-light-setup topic.
Feel a bit stupid , but I cannot get the fill-lights-setup working...
I deleted my existing lighting nodes, turned off GI (GI rel detail to 0 and GI sample quality to 0, right??),then inserted the fill lights.tgc. In my preview window I can see the changes when I adjust color and strenght, but when I render: just a grey landscape, what ever I try. I múst be doing something wrong, tried the last two hours to find out, without result...
Which fill-lights? If you mean Oshyan's, they should just work. Same with Moodflows, but Moodflows can work with the scene as is without deleting anything. Of course, Oshyan's can too, but his has a sun light included, while Moodflows is multiple suns.
I used Oshyan's fill lights setup. Preview window shows it works, but why not with a Full Render ...???
Post the TGD if you can. Let's look at it. I have about a half-hour I can look at this.
Maybe my render settings are wrong? Forgot something?
Detail: 0.5
AA: 5
GI detail: 0
GI sample: 0
GI surf details: unchecked
Attached two pictures: 1e with modest Fill Light strenght setting at 0.5, 2e with overexposed Fill Light strength setting of 3...
Since I can't see the TGD, I don't know. Have you tried rendering from 1K above the surface to make sure you aren't behind or underneath something?
tgd file attached, thanks Calico...
Sorry, the tgd-file I send you was not the latest one; include that one now...
You could try to turn off the cast shadow in the fill lights.
What I disproved is that the lights are not working correctly. I did this by bypassing the two loaded heightfields (which I obviously wouldn't have) and hovering over the generated heightfield. At about half a kilometer up, this is what I could render. I'm not certain of the problem, but I'm certain it isn't the fill lights.
Is it possible your atmosphere has been dabbled with beyond usefulness (just asking)? The haze Horizon color and the bluesky Horizon colors have both been changed from the default. I've found changing many things in the atmosphere is better accomplished one setting at a time and thoughtfully. It's just a guess, but I'd look there first.
Also, your cloud quality should be at least 64, but I would use 128.
I need to leave. Try different viewpoints as well as verifying that where the sun is shining actually is showing up in your environment. I wonder if your loaded heightfields are just large enough to cast large shadows.
Thanks Calico for your patience and quick answers; I'll look into your comments; meanwhile I tried Volker Haruns suggestion and that worked! Thanks to both of you for your kind help and replies...
I've noticed that there are some strange displacement problems in the power fractal "Basis grijsgroen", which I think is a problem with very small values for "smallest scale". This is a bug I will need to fix.
In your scene it is creating massive spikes that shoot into space. This bad displacement could also be the reason why the fill lights are casting shadows where you don't expect them to. I would disable the displacement in Basis grijsgroen or change the smallest scale to something larger, e.g. 0.1.
Matt
Thanks Matt, I scaled the displacement down to 0.1. When I turn on the cast shadows in the fill light now, it renders correctly now, not a gray (shadowed) landscape but one with the intended colors! Still it's not easy to find the right settings in the fill lights to come up with the right appearance. But I keep trying... :)
Working with the fill lights setup and reading around on the forums these days (Oshyan's fill lights, Moodflow's), I tend to think it's better at the moment to turn off GI anyhow. It won't be as easy as that I think, but anyway I see some advantages:
-a great (very great!) decrease in render times
-more possiblitities to adjust lightning
-with GI turned on, a small (and I mean real small ) change in camera point of view will change the lighting in the final render dramatically; even so: crop render with GI turned on differs a lot from the same part in a full render of the whole picture, etc. So GI off means more "render certainty", you know what you will get...
There must (?) be a loss when turning GI off I guess; shadows look much harder now I believe, but maybe that means more tweaking in the fill lights settings...(?) I have to practice a lot I guess, but
I believe it's worth it: never saw a render engine that could produce such picturesque and crispy renders...!
Matt,
I mentioned this once before in the Support forums, though I think I had a couple of other issues with the TGD that I had caused, which may have masked this very same problem. Once I changed my odd displacement value (among some fake stones), I got my light in the atmosphere back.
Quote from: Matt on July 21, 2007, 09:19:14 AM
I've noticed that there are some strange displacement problems in the power fractal "Basis grijsgroen", which I think is a problem with very small values for "smallest scale". This is a bug I will need to fix.
In your scene it is creating massive spikes that shoot into space. This bad displacement could also be the reason why the fill lights are casting shadows where you don't expect them to. I would disable the displacement in Basis grijsgroen or change the smallest scale to something larger, e.g. 0.1.
Matt