Quote from: TheBadger on January 03, 2012, 08:19:05 PM
Really Im just trying to understand why there is so much disparity between everyones renders. That is, why is your work here so real looking, and why does some of my work look fake? I am trying to identify the key setting and there optimal values that put everything in the ball park. I have to admit Im not going at it very scientifically, because every render is different there are to many variables. Nonetheless, I believe (incorrectly?) that seeing the file will help. And I would like to be sure at least that I'm doing everything I should, even if my settings are off.
Hi,
after 11 or so years of using Terragen and using TG2 since (if I remember correctly) 2005, I think I have figured out a little bit of what makes a realistic looking picture. I know from my fellow NWDA artists that they all agree that especially point 3 is of utmost importance. Anyway, in my experience it can all be boiled down to the following guidelines:
1 - Scale is important. All scales need to fit in with each other. It's most simple to stick to real world scales. Think of trees: out of the box, they come in real world scale, say a tree is 10m tall. If the tree appears to small, then it's just too far away and not too small. Maybe if it appears to small then your other terrain features or objects are too tall? Another example is the scale of waves on a lake. On the average lake, you don't find 10m long waves, so don't use the default settings, which are more suited to fit to an ocean scene.
You may also choose to work with fake sizes, but then you have to work much harder to keep scales of various scene elements in balance.
2 - Render quality settings. Just don't do a "final" render on mediocre quality setting. I.e., don't render with AA = 3. Good quality takes time. Like when buying a car, if you want quality you have to pay for it. With cars of course, if you want quality you are pretty much limited to buying German car maker brands
So what are the right quality settings? That depends on the image, but in my experience you don't go under AA 6 for vegetation, and GI of 2/3. I think that's a reasonable minimum to begin with. That being said, these settings for "final" renders. And with render detail I find that 0.75 is reaonable for screen size renders, but you might want to adjust that depending on the scene as well. However the render quality settings are the LAST problem, not the primary ones!
3 - Color & Lighting. If you understand this part, you've got the holy grail of making a realisitc looking image. Let's take Impressionism as an example. Made with just pretty large and rough strokes, you can't see much detail at all in the paintings of that period in time. But still the images look incredibly realistic. Why? Because they have chosen the perfect and absolutely natural colors, as in the original scene. That principle still holds true to your renders. If you make a single poor choice for the colors of a leaf texture, or a fake stone color, or anything really, it will make your render look fake. So pay extra attention to choosing the right colors! Secondly lighting. Most people don't think a lot about that TG2 works like a real camera with a limited dynamic range. If you walk around with your pocket camera and take a shot of say a house against a brightly lit sky (even if it's cloudy), you need to make a choice whether you want to expose the brightness for a good shot of the house, or a good shot of the sky. Usually you can't have both. So what most people tend to do in TG2 is to expose for the sky, although the center of their image is the ground with it's vegetation and objects, resulting in a way too dark render. Or, they want to find a compromise, but that usually results in a dull render with neither the ground nor the sky being exposed good enough.
Like in photography, you need good light on your scene to make a good picture. Try to get a good mix of directly lit elements and shadow. If your image has too much shadow or too much light, it probably won't look very good, even if everything else is realistic. Lastly, try to let the sun shine on your scene from the side, at least a bit. Oh, and low sun elevation is better than high noon. The default 25 degrees give you good results for daylight scenes, don't go to 50 or - god forbid - 90 degrees. It will be so much harder to make a good looking render with these settings. Of course sometimes you will want to have a high sun, but in most cases you probably won't.
Anyway, play with the exposure slider and dare yourself to push it up a notch or two.
4 - Detailed Objects - Don't use low or medium poly objects EVER in the foreground or midground. These will immediately sell your render as fake. If you don't have HD objects, such as Walli's NWDA HD Pine trees, just don't put any objects in the foreground, where the simple geometry and low res texture is immediately apparent. I am sorry for having to make this sound like an ad, but it's true nonetheless. Every image I made with low poly vegetation in the foreground actually sucked, and the xfrog libraries don't give you high poly objects and HD textures out of the box.
If you look at Darthvader's render here, I believe he used the xfrog library trees, which are quite low poly, but he wisely put them into the far midground where it doesn't matter much. There is just one foreground tree, but Darth made a good choice with blurring it "away".
5 - Pay attention to detail - Don't go for the quick win. For example, you don't just throw a population of bushes on a terrain, even if the bushes themselves are of great quality, in reality they don't tend to grow everywhere with equal density. Go the extra mile and make a distribution shader for your population that clumps your population together in places and leaves other places empty. This usually requires a lot of trial and error in the beginning, but it is so much worth it. Another example of where you should pay attention to detail is fake stones. Sometimes it's like people are so amazed with the ability to create stones everywhere that they forget to bother about making them look realistic: color variation, size variation, distribution variation, detailed geometry... all that is important detail. I usually have around fifty to a hundred incrementally saved tgd's of the same scene on my hard drive before the image is good enough for a final render. Take your time with tuning detail. If your render isn't detailed, it will not look realistic (in most cases).
I think that's pretty much it.
I am confident that abiding to these guideline will make any image look a whole lot better.
Regards,
Frank