Render white object as white?

Rendering
1

With Rhino Render, a white box in a bright sunny environment is rendered as gray (white_box.3dm):

How do I best make it appear as white, resembling how it would be seen by the human eye?

I know I could just increase gamma, but there are many other parameters in settings for exposure and environment. Also I noticed that in the environment there are spots brighter than the box. This is unexpected as the material of the box is 100% white.

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Rhino Render does not have the ability to use a separate color for the skylight which is why you get a blue cast using an exterior HDR like this one. In more advanced render engines you can specify that an alternate color is used for the skylight instead of the HDR itself. With that said, you can make the box more white by reducing the HDR texture saturation in it’s output adjustment settings. .2 saturation and a multiplier of 1.5 give you this…


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Could I alternatively adjust white balance, just as I would do when taking a photo under the same sky?

HDR multiplier, or the multiplier under Output Adjustment / Color adjustment?

4

You could adjust white balance but I don’t think you’ll get rid of the HDR color values as easily. If you want more control over image based lighting in Rhino I’d suggest a more advanced render plugin. The Brazil eval with Neon is one option.

I adjusted the multiplier in output adjustment for the HDR but the main multiplier will do the same thing.

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Thanks, @BrianJ!

What I don’t understand: Why do I even need to adjust these values?

I was assuming that the purpose of using HDRI lighting is that I get a realistic result without any adjustments. Maybe the Mt. Monadnock HDRI is not white balanced properly?

Concerning more advanced render plugin: These things are generally expensive, and rendering is really something I only need occasionally (and I’m quite bad at it).

6

My suggestion above is a free option.

I’m not 100% certain but I believe I shot that with auto-white balance off to help the bracketing and stitching. I may not have since I was hiking and probably in need of a snack… excuses excuses… but you can adjust it all you like in any 2D editor that supports 32 bit images and the HDR format. My experience has been that exterior HDRI’s lean toward a blue cast.

It’s subjective but I’d say because you can and it’s art. Imagine you wanted to have some of the HDR color but not all of it influence the render for realism.

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