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View Full Version : Can someone please explain HDRI?



dhatch01
08-26-2005, 01:38 PM
Okay. I'm stupid. I need this explained in simple terms because everything I have read on the internet so far is way over my head.

I know basically what HDRI is, but that's it. I don't know how you create the HDRI images or how to use them in a scene.

Is there a simple tutorial out there or is this just not a simple thing?

Thanks!

Dodgy
08-26-2005, 04:41 PM
HDRI is high dynamic range lighting, and what this means is instead of a fixed range of colours (0-255 for each channel) the image is stored with higher precision, with colours that go brighter than 255. To make these images you either need a a HDRI camera, or use an image processing program to boost the range of ordinary pictures. These images are usually signified by the .hdr extension, and these can be loaded into LW as normal Images. To use them for lighting a scene, add the environment plugin ImageWorld (in the Backdrop panel) and select the loaded hdri image there. This will mean it will show up in reflections which are set to either raytracing and backdrop or backdrop only.

To have the image LIGHT your scene, turn on radiosity and use one of the three types. Whichever you choose, the scene will be lit by the HDRI map.

Also, when you render with HDRI, you might find extra bright spots appearing in reflections and such, which don't anti alias properly. Turn on 'Limit Dynamic Range' in the Processing panel (the same as the backdrop panel, just on one of the other tabs) and this will sort out the AA.

Yamba
08-26-2005, 10:05 PM
Hi dhatch01

I found this tutorial some time ago and it helped me through the HDRI maze hope it assists you.

http://www.the-worms-of-art.com/tutorials/lightwavetutes_221.html

Regards
Yamba :beerchug:

dhatch01
08-29-2005, 08:23 AM
Thank you both! This was a world of help!

Lightwave user since 5.6 and still a noob.