problem whit hdri+sun

[Daniel79]

I'd like to use hdri+sun for lighting a scene.
When i add hdri whit power=1, sun power=1, exposure=1 the image is overexposed, is a bug or i'm wrong something?
Please helpme, i use rhino plugin whit octane render 2.20....

Thanks a lot

[face_off]

Firstly, if you are on the plugin version 2.20 - that is very old, and you should update to the latest 2.25 version (2.25.0.64).

You should set the gamma for the IBL you are using - so if it's an EXR or HDR, use a gamma of 1, otherwise if it's a PNG or JPG, use 2.2. If it is too bring, either reduce the IBL power, or the sun power to get the look you are after.

Also - you will want to position the Rhino sun in roughly the same position as the IBL sun. If you are using a HDR, you can just use "Texture Environment" instead of "Daylight Environment", since the sun is already in the IBL (otherwise you end up with 2 suns - as you have).

Paul

[Daniel79]

thank you very much!!
Today i try to reduce the exposure of hdri whit PS and now the image work fine, but your answer is perfect for me!
I want ask information about teture for best bump/ roughnees/ specular...
the image that i have to use is ok a RGB jpg desaturate or i need a jpg in gray scale with no color information?

Thanks a lot

[face_off]

I want ask information about teture for best bump/ roughnees/ specular...
the image that i have to use is ok a RGB jpg desaturate or i need a jpg in gray scale with no color information?

Either a n Image or a Greyscale Image will work fine - you will need to experiment with the specific images you are using to get the best result.

Paul