In this new tutorial, I will guide you into making a simple self-made HDRI from scratch, without the use of a photo camera. As you may know by now, an HDRI-image is the simulation of light in its natural state: as a high dynamic physics feature. Otherwise, simply Google HDRI and find all about the subject. The human eye is so fast in adapting to different light situations, and your monitor is actually so bad at representing the enormous space between the inside of your jeans back pocket at night and a bright day at the equator, that the fact that the sun is so powerful may strike you only after a day on the beach without a proper sun block. I guess the 32-bit room that we will use is still far from insufficient to capture the whole range between dark and light but it does do an extremely well job.
There's a lot of HDRI photo material available from parties such as 'Sachform
' and 'Dosch Design
' that can be very useful in giving light and atmosphere to your 3D-scenery. But when your client wants a simple classic four-window reflection in his water drop, none of the beautiful things they sell, nor any of what you will find that is free to use, will do. Then of course, you do it yourself!
Apart of course from any major 3D package, you will need Photoshop CS2, in order to be able to merge a number (I will use 7) of "lighting situations” into a single radiance document. This radiance document will have a 32-bit range of dynamics, enough information to actually light your scene, throw shadow and make reflections without the use of specular shaders or channels. I won't go into minute details of setting up the scene.
The final render before we proceed: This image and the shadow are purely made with the HDRI that we will make ourselves without the use of a camera. For the sake of purity I haven't edited the image afterwards:
This is the render.
HDRI from Scratch
The first thing that we do in Photoshop is making a simple pure white window in the middle of a 50% grey background Set it to 850x850 pixel and 16-bit colors and save it as 4.psd.