In the last few weeks I’ve got several emails, where you guys asked about tips & tricks on increasing render speed ,while maintaining (or even increasing) render quality. Since different settings are suitable for different types of scenes, this is not something I’d be able to summarize in a few sentences. So I dedicate this post to collect and share some settings I found useful.

These settings are partly the results of my experiments, partly tips Michel has shared before. The settings are optimized for outdoor scenes, and focus on getting noise-free, sharp renders.

If we want to render good quality images in shorter time, we need to follow two golden rules. The first one is, if the render doesn’t look good enough in your preview, it won’t look good after the final render either. If the preview render is too noisy due to low atmosphere quality settings, there is hardly any chance to get the noise completely removed, even using high Anti-Aliasing settings (that can really make the rendering process slow). If the clouds are too sharp, they will remain sharp, regardless of your render settings. If the bump is too strong on your foreground plants, no render settngs will change that. The Anti-Aliasing strategies listed below are very useful to improve the overall quality of the image, but you need to take care of all the details and fix every little issue before starting the final rendering.

Before moving on to the second golden rule and the AA strategies, I’d say a few words about the atmosphere. Realistic lighting equals to Global Radiosity is something I always mention; these strategies are optimized for GR lighting. Let’s see the Light tab first. You can decrease your render time without virtual quality loss by decreasing the GR quality boost to -0.5. It may not sound too much, but it counts. If you have lower PC specifications, you can decrease it to -1, or even -1,5, but -1,5 will already show a slight difference in quality.

Let’s take a quick look at the Sky, Fog & Haze tab, more exactly to the global quality boost slider at the bottom. By default it’s -1, and it may be enough for a cloudless atmosphere with no volumetric sunlight. But high quality renders require volumetric sunlight. Our Sun is not simply a directional light which is not affected by the particles found in the atmosphere or objects that block its way. Volumetric lighting is what creates realistic godrays through the clouds, rays in a forest or beams coming through a window, and it also gives a stronger contrast between highlighted and shaded areas. Sounds perfect? …It’s not. It also creates noise. Noise on clouds, noise in the atmosphere, and in the whole scene. This is where you can’t fully rely on AA settings; a proper global quality boost is also needed. The AA strategies work best with a quality boost of +2 or higher, but it also depends on the scene. If you don’t have any cloud layers (or metaclouds), +2 is enough for a HQ render. If you have less dense, soft clouds, a boost of +2,5 to +3 is necessary, but if you have dense, sharp clouds, a minimum of +4 (but maybe higher) is needed. Of course your PC specs count a lot, but sometimes  the longer the better. And with the right render settings, you can decrease render time compared to better presets like Superior or Ultra.

Now it’s time to….grab a coffee and take a break before all the information piles up :D ….so let’s reveal the second golden rule; do NOT use preset render profiles. Yeah, Vue ships with several render presets, but they either don’t produce high-quality renders, or they contain more boost in some features than necessary, making the render process slower. A general and obvious fact about render settings; the higher the number is, the slower the render is. I would like to start with those settings I use the most. From all the settings listed, this is the fastest.

Believe it or not, the basis of this custom render profile (which I just call “Fast & Sharp”) is the Final preset. Yes, with some tweaks you can get pretty nice renders in a short time, even from loading the Final preset. To be able to modify settings, you need to select User settings, and load the Final preset from the Environment folder in your Vue installation. The screenshot below shows the render settings.

As you can see, I disabled Depth of Field in Render quality. Unless we are about to render a scene with DoF blur effect, it’s not needed. I decreased the Advanced Effects quality to 40%, but if you’re not in a hurry, you can leave it at 46%. Now let’s see how different Anti-Aliasing strategies work with these settings.

The AA settings in my custom “Fast & Sharp” profile are the following:

I’ve used these settings in 98% of my newer renders; you can check them and decide if their quality is good enough. I’m pretty satisfied with this profile; fast, uses just as high settings as needed; works well in most types of scenes.

Now let’s see those AA strategies Michel has shared. The first one is the so-called Classic Adaptive Sampling Method.

Just like the prevous strategy, it works well in most cases, maintaining a good balance between quality and render speed. It uses Crisp AA strategy, which can give a perfectly detailed, impressive results, although the render can be a bit noisy with lower quality settings. The 70% quality and a bit more subrays/texels are necessary. There is only a little difference in render speed between these two profiles.

In this method, we are forcing a minimum of 8 samples per pixel. This can be useful if you have a lot of meshes in your scene with hard or slanted edges, like building, vehicles and other objects. This profile is a bit slower, but considering the nice results, it’s worth the wait.

The last two profiles are suitable for scenes with heavy atmsopheric features; thick fog, dense clouds, intense godrays etc… and scenes full of complex textures as well.

The same strategy as in the second method, only this time, we increased the quality to 90%, this will make Vue eager to fire more rays at the object if it decides more rays are needed. This method will be SLOWER.

The slowest of all, bit it gives the most beautiful results, if you have dramatic atmospheric features and a lot of time, you can give it a try.

Of course there are several other variations you can experiment with, but these are the profiles we’ve tested with different scenes. To summarize it all, the first two profiles are suitable for most of the scenes, but in some cases you need to go higher in quality boost. The main goal is to find the right balance between quality and render time, which is not easy, but I hope this post helps a little. I suggest you rendering smaller areas from the scene first to check if your profile works well. There’s nothing worse than waiting for long hours for a render, then finding out it’s not as good as we expected. Thanks again to Michel for his tips!

Additional tip to increase render speed: if your scene contains large-scale ecosystems, select the leaves’ materials in the material browser, click Edit material, and reduce the subray quality drop to -2. This reduces fine calculations and decreases render time without virtual quality loss.

Well…that’s it, friends! Now you can understand why I chose to include all of this information in a post rather than including it in response emails. Thank you for reading this post, I hope you found the answers to your questions. :)

© 2012 Drea Horvath - 3D Landscape Artist Suffusion theme by Sayontan Sinha