Rendering: Creating HDRI for reflections

[magnoborgo]

Just use Panoramic Transformation to transform the Mirrored Ball to a Latitude/Longitude Image, and map it to a big sphere in your scene.

As you are not planning to use it as a hdri light source, you may save it to a Low Dynamic Image format (normal tiff, jpg, etc) and if necessary do some adjustments in photoshop.

;D

[Kel Solaar]

As you are not planning to use it as a hdri light source, you may save it to a Low Dynamic Image format (normal tiff, jpg, etc) and if necessary do some adjustments in photoshop.

I think that it's a bad idea to convert the HDR picture in a LDR one because he will clamp all the lightning data of his HDR image, resulting in a LDR picture with white color clamped to 255. The problem with this is that he can't get the bright specular reflexions produced by an HDR picture.

ssyed:
I don't want to do the whole "diffuse/specular convultion" it takes for ever. I heard you don't need to do it if you only want to use HDRI for reflections.

No you don't need to do it with your reflexion HDR map. When I render with HDR, i use two maps: one for reflexions (about 512*256) and an other one for lightning (64 * 32) with a diffuse specular convolution filter in order to have a less splotchy render
. These two map are adjusted so they will display correctly at gamma 1.0, this is very important because if you load them directly whitout this adjustement the maps will be very dark because max load them at gamma 1.0 and you view them at gamma 2.2 in HDRShop.

[gmask]

Originally posted by ssyed
I want to create and HDR file from pictures I have taken. I don't wnat to use these for lighting only for reflections. How should I do this? I have HDRShop, and the mirrored ball, I don't want to do the whole "diffuse/specular convultion" it takes for ever. I heard you don't need to do it if you only want to use HDRI for reflections.
Please help :p

BTW what program are you using?.. there is a fake on www.pixho.com that is great for Maya may work with other programs as well.

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