In this tutorial I´ll explain how to create full spherical panorama renderings within 3Ds Max with VRay. You can use this technique to create panorama tours through architecture, skydomes for image based lighting, animations in planetariums or amusement parks or just for fun. Usually for QTVR you would use the included panorama exporter from 3Ds Max, but using VRay and Global Illumination you would get different looking images for each side of the cube, because each side would be rendered as one image separately. So when GI is used, the corners / connections between the sides would not be consistent and therefore this method is not well suited for panorama renderings.
In order to render proper 360° domes or spheres you should use the VRay camera method that is also suitable for animations. But first its important to know the final purpose of the 360° rendering, as it may make a difference in setting up the camera and render parameters. Do you want to create a Quicktime-VR for the web where you can navigate within the image and turn around ? Or do you want to create a skydome animation for a planetarium, or a full sphere animation or just a 360° panoramic image that is limited to the top and bottom ? The following images illustrate the differences:
Lets start with a full sphere 360° panorama. Reducing the size or ratio of this panorama is easy, so its good to understand the full sphere first. As mentioned above, 3Ds Max has a built in “Panorama Exporter” that is suited for easy creation of QTVR with the Scanline Renderer. But when working with VRay and Global Illumination, its not suited. When you are using VRay, you should use the VRay Physical Camera and set the type to Spherical and 360° within the render settings camera rollout and the image render resolution to an aspect ratio of 2.0 (e.g. 1000 x 500 or alike). This is important in order to get non-distorted renderings with this camera setup.
If your settings are correct, the rendered image should look something like this:
If your settings are correct, the rendered image should look something like the image above.
Now the question is what can you do with this equirectangular format ? Actually you need to convert the image into a format that is readable as QTVR or as Domemaster (a domemaster is commonly used for planetarium and dome projections).
QTVR uses a cube with 6 sides to interactively display a panorama on the computer or within websites. You can either create these 6 sides by converting the image with a software like PTGui or Cubic Converter for example. Some website panorama players also read this format directly, the PanBox360 Flash Player for example is a simple and good solution for fast embedding of panoramas in websites.
For cylindrical and skydome panoramas, you basically just need to crop the rendered image bottom 50% (Skydome) or top and bottom for the cylindrical panorama. Of course you don´t want to render full 360° x 180° images and afterwards crop the images. This would use too much rendertime. You can crop the images while rendering, just by setting the render region corresponding to your needs in the render window.
If you want to render dome master images directly, without the need to convert the equirectangular image after rendering, there is another very easy camera in VRay, the VRay Dome Camera. Using this camera, you can easily render skydomes or dome masters directly from within 3Ds Max.
This so called dome master should have a resolution of 4k (4096 x 4096 pixel) in PNG format if you want to use it for projection.