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Richard Hebert
04-22-2015, 08:13 AM
I have some free HDRIs that have different brightness ranges. Is it possible to clamp an HDRI to a certain brightness level within Lightwave? I would like to swap them out and still keep a consistent brightness level in the scene file. Thanks for any thoughts.

MonroePoteet
04-22-2015, 09:47 AM
I don't know if it will suit your needs, but there is a Limit Dynamic Range toggle and range at the top of the Processing panel (CTRL-F8). There was a fairly recent discussion on caustics:


http://forums.newtek.com/showthread.php?146273-Caustics-question

referencing a video by Chris Wells on Vimeo:


https://vimeo.com/123362353

where he talks about HDRI (calling them Light Probes) with great intensity range.

mTp

Richard Hebert
04-22-2015, 09:20 PM
Thanks for the tip. While not the 'Holy Grail' it will work in a pinch.

MG artist
04-23-2015, 06:08 AM
The exposer filter found in image editor, under the processing tab is your best choice. You shouldn't use limit dynamic range for something like this, it is useful only if there are bright spots appearing in your scene even if the HDRI looks good or to reduce radiosity caustics rendering time by clamping very high color values. If you don't need all the control exposer has to offer, you can simply reduce layer opacity from textured environment.

Richard Hebert
04-23-2015, 07:36 AM
The problem was from a light probe image that caused speckling. I adjusted the surface settings to accommodate the light probe and everything was fine until I used a different light probe. There is such a large disparity in light probe ranges. Differences can range from 2000% to 200,000%. How does one set up a surface to react realistically under these drastic conditions? I guess the real question should be... What lighting convention should I use to make adjustments when creating a material?