Join Dave Schultze for an in-depth discussion in this video Geeky definitions you should know, part of Rhino and V-Ray: Rendering.
In this video, I'd like to cover some of the most common terms used by 3D geeks like me. These are terms that many courses assume you already know and then never bother to explain, which drove me crazy enough to make this one video just for definitions. This is a pretty short list so don't worry about having to learn a whole new language. We'll start off with the term Global Illumination or GI. Now this is a cool rendering algorithm or engine, you could even call it a process, that is used by V-Ray and other software to calculate even lighting for soft shadows and soft illumination.
It is very easy to set up and use. Here's an example to the right of the penguin. And you can see that the lighting is very even and the shadows are very soft directly underneath the penguins feet. Now it's also worth noting, V-Ray's going to be using two render engines in series. The first one will be calculating GI or Global Illumination. The second rendering engine or process is called a Raytrace. Now, here's an example of a rendering using only Raytrace processes.
V-Ray uses Raytracing type engines for the second pass. Which includes secondary bounces and details. This is the light emanating from specific lighting in the scene, like a rectangular light. Now, one of the ways you can recognize, this, is, we have much sharper shadows underneath the penguin here. We also have very distinct highlights. Also, in the background, you'll notice it's considerably darker, when the other one was much lighter almost disappeared. And that's because we're using smaller, kind of defined rectangular lights that can only illuminate for a specific distance.
'Kay, next topic up is Skylight or Light Dome. These are V-Rays 2 different types of GI both of these use a dome as if it were a glowing sky to cast even lighting into a scene. Now i've got a dome here to show you but you'll never see this in the scene, it's more of an imaginary dome to get the results of this imaginary dome. You do have to do a rendering and you will not see it in the view board. I mentioned there were two types, Skylight or Light Dome.
We'll be using Skylight only for the majority of this course. On a related note we have Image to Base Lighting. So it's also using a dome, which is for the environment and we don't see. But we're taking an image and wrapping it around that environment. So here you can see it kind of on the outside. And if we zoom in this is what the graphic I created looked like originally. So it's just a simple gradient going from black to gray and I just quickly in Photoshop drew a couple of shapes to simulate lights as if in a studio.
The advantage of using this over the Skylight which is a single color is we have more variations. We have areas of light and dark which, when rendered, will look much more realistic because of the variation of those colors casting light into the scene. Final definition is two-fold. Let's start off with the one you're most familiar with. And that this LDR, or Low Dynamic Range. A file example of that would be a JPEG. You may not know it's got 8 bits, which you probably do know is that gives you 255 shares of both R, G, and B.
All three. Resulting in roughly 16.7 million colors. And I've got an example of a color wheel floating on top of the penguins head just for reference. Now the amount of colors in LDR is also matched by most monitors. So the range of an LDR image, like a JPEG, is a perfect match for all monitors which have the same amount of colors or color space. However, this is a bad match for the real world. Imagine going outside and looking first under a rock and then up at the sky.
I think you'd agree that there's more than 255 shades of value between those two locations. So the. New file format or newer of HDR has been invented to solve that problem. Typical file format is dot HDR and its of 8 bit, its 16 and up to 32 bit. That will give you R, G and B of up to or sometimes more, 65,000 shades which results in literally trillions of colors. So it's worth noting, also, that V-Ray will be using HDR calculations in all of it's renderings, even though, when you complete most renderings, you'll be saving out to a LDR, like a JPEG.
So that brings up the question, if HDR images contain more information than a monitor can show with this higher range of values, why do we care? Well, using simple tools in V-Ray, you can squeeze or modify some of these ranges of values into where the monitor can see. The result is a much more saturated image with vivid colors. Anyway these tools are very straightforward to use. But we will only be covering towards the end of the course. After we have covered the basics.
- Why use V-Ray?
- Installing DR Spawner
- Understanding 3D terminology
- Activating V-Ray
- Adjusting quality settings
- Get quick previews with the material override
- Understanding lighting types
- Exploring materials in the Material Editor
- Creating your own materials
- Texture mapping materials with bitmaps and procedurals
- Saving time with V-Ray presets
- Getting the right size for your render with output settings
- Working with environment lighting
- Strategies for working with cameras and camera settings
- Ensuring accurate color for your scene with color correction
- Rendering tips and tricks