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Probably a stupid question but I can't seem to get Octane to just use HDRI as a light source. I have turned down the sun/daylight and added an HDRI I want to use, but no matter what slide I slide either in Carrara or Octane window seem to make any difference.

I know it is probably something so silly I will smack myself upside the head when someone says it

Here is a screen grab of the setup used with the image for reference - the only "light" in the scene is an HDRI. Note that there is no atmosphere, you don't need it to use HDRI lighting in Carrara. I use the Gamma value for the HDRI to adjust doth the color sharpness/intensity and the light/sun intensity. Not all HDRI are created equal, so there aren't really any "one size fits all" settings, but the closer you get to 2.2 (or more), the more intense/focused the sun light will become, and the more defined the shadows will be. Lower values will give softer lighting and shadows.

Hope this helps!

I see you have the sun level at 10, so I am guessing I will need to have some light coming from the default Octane light, Will mess about and see what happens

ArtistX1 wrote:I see you have the sun level at 10, so I am guessing I will need to have some light coming from the default Octane light, Will mess about and see what happens

Actally, that's the Octane Environment level/intensity (which in this case is just the HDRI). If you look closely you'll see that the Carrara atmosphere is set to "none". Carrara sky's or realistic sky's must be enabled to have a sun in the scene (or maybe you can add it through the browser?). The Sun controls for the Octane environment are alway's there - with or without a sun.

One simple trick that can really help to get your HDRI set up and oriented properly is to add a sphere to your scene and give it a chrome or polished aluminum shader (something reflective). It will help to determine exactly where the sun is in your HDRI so you can rotate it to give the proper illumination direction for your scene.

Always something else to try

Thanks

I made this one with just the lighting from the background image. In this case a hi res jpeg.

Maybe I am doing something wrong or using the wrong HDRI, will look for some new ones, or I could make some of my own Fake HDRI when Head feels better

There are many very good and free HDRIs around if you do a search. Start with the sIBL images at HDR Labs:
http://www.hdrlabs.com/sibl/archive.html

Hi Phil

Think that was one of the first places I cleaned out a while back, I guess I really should recheck a few places and update my collection :p

One of the nice things about the sIBL collection is that most have an info file which gives the camera height and gamma of the image, so you can set that in Carrara to match the image very well.