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View Full Version : HDR and Transparency issue



seventh
09-11-2003, 06:48 AM
Hello. I am wondering if anyone has had this problem. I decided to re-render and tweak my car http://vbulletin.newtek.com/showthread.php?s=&threadid=2230&highlight=Eclipse
(btw I used to be banshee, new email and web created the change. I've got the wires too, so no controversy). This render was GI 110%, 2bounce, 8x24 with a HDR in image world at 300% for better highlights and G2 for additional boosts. If you look through the glass, you pretty much see the white background (and reflections). I achieved this with a small poly-backdrop 100% luminous no shadows etc... The problem I was having and am still having is that if I remove the polys and use a 32x32 white image as the backdrop in the compositing tab, the HDR would continue to show through the glass where one would think that the 32x32 would and should be visible instead, thus giving me a solid white background, thus the compositing. I have done various tests and have found that if I use a non-HDR in image world, I don't have this problem and I get my white background but unsatisfactory GI and "truer" highlights that HDR's provide. I would assume that with the higher dynamic range of the HDR, maybe it is cutting through everything. I tried to reverse my initial settings (imageworld to 100% and GI to 300%) but no go. Thought it was something with G2 but no. Single sided, double sided, adjust transparencies, increase/decrease ray recursion etc... just about everything. The only thing that I have not tried is making the 32x32 white image into an HDR itself but I doubt it. Is there anything else to try? Is the poly backdrop the way to go? Is it a miss-handling of HDR with LW? Any insight would be wonderfully appreciated. Btw, using LW7.5b on PC 2.4ghz 512 GF4400ti
Thank you again.