Rendering the Image
At this point, I'm happy enough to start a serious render. Not everything is perfect and it doesn't look photoreal, but I have faith in the way things were going. This is another step where experience will tell you say if it's the right time or not to go to post-render work. On the other hand, you can always come back and tweak stuff, so if you feel like throwing your renders into Photoshop and playing with them give it a go and see what happens.
It's time to prepare everything for Photoshop now. It's not just about the render at this point, it's also about all the things you can use in Vue that could help the tweaking process later. Enable the multi-pass render, and start adding stuff that you think could be useful. You should always render passes like ZDepth, Indirect Illumination, Shadows, Reflection etc, plus object masks, material masks and any other thing you think might help. Be careful though; this will increase your render time, so if there is a time constraint, keep it under control.
Be careful with the output PSD file. All the layers will be locked and there will be a lot of information in extra channels (object alphas, etc). When you open the PSD file look around and try to think about the way that you could use the extra passes. They will have several blending modes which can be changed by default, so take a look at how they look in Normal mode – you might be surprised at the effect (Fig.15). Here is the render with some extra passes on the bottom. So the work is done now, surely? No, not even close (Fig.16)!
The Photoshop Processing
As I said earlier, what I'm actually looking for in my Vue render is a good base to work with. That means that I want all the elements in place, I need the lighting, I have all the extra passes, so all I need to do is tweak all this information to get the best result. In film visual effects, the result of the CG pipeline is what we have at the moment and it's the role of the compositor to make all the elements fit together nicely. Of course, this is just a simplified description of the actual process, but the principle is the same.
The reason behind all of this is simple: speed. At this point our render times are already a bit slow. A change in the color of the water will take way too much time to render. However, having the water as a separate element in Photoshop, allows us to do that extremely quickly. So we can be flexible and creative, and most of all, results driven. Having good references will come in handy again, because right now we can actually have the two next to each other.
Only one question could arise. Given the fact that we are processing the image in 2D, aren't we losing the power of 3D? What if you have a moving camera in your scene? Well, at this time, this is not our goal. We just want to create a good looking image using the power of Vue. And that is still in reach. But, don't worry; there are a lot of techniques to do exactly the same thing using this process. It's not the purpose of this tutorial, but I will probably talk about this subject in a later article.
I am sure you've noticed that I haven't talked much about the sky at all. Well, there is a reason for that. Even though Vue skies look good, in most cases there is simply no need to use a CG sky. There are tons of amazing picture libraries that you can use, and the result will be well, photoreal. This is what you would do in real-world production where time is an issue, so unless you have a good reason for it, I wouldn't spend too much time trying to get it to look right. I choose a very typical daylight sky, because I don't want the image to look too dramatic. The goal is still a natural looking image (Fig.17).