I'm fairly new to Houdini and am doing a lot of tutorials. Every one of the tutorials show a viewport display that does not match my view. I've looked through all the display settings I can find and verified that they are set to default setting. I've tried messing with the gamma and messing with light exposure.

What I'm always getting, whether with a polymesh or a volume, is an object that is much darker than the tutorial, and when adding lights the lights are darker. I'm attaching an example image below.

Right off I can see that the tutorial is produced in 15 or older and I'm using 16. Can't tell as the version is not in the title bar like in 16. Was there an display upgrade or change from 15 to 16?

Can anyone give me any tips on what else to check or change?

I am running 2 nVidia GeForce GTX 1080's with driver 385.41 on Win 7

Thanks!

Do you have the OCIO environment variable set for some other app? H16 supports it, 15.5 and lower does not.

As far as I can tell I have not set any variables other than $JOB and I looked thru the list in ‘Alias’s and Variables' and saw nothing.

Under what conditions would I use the ‘exposure’ control on the light? I've found raising the exposure to a value of 5 on both of the scene lights I can get it to match what I'm seeing in the tutorials. However, that has to be wrong.

At a loss.

thanks

Just in case it is helpful, here are two objects with two lights set to intensity of 1. FYI- gamma is set to 2.2 and HDR Rendering seems to make no difference.

Hi, when reproducing your scene above, I remembered two things that might help.

1/ A lot of users will use the camera to place lights by control clicking the shelf tool and this automatically adjusts the exposure. (usually increasing it)

2/ I don't remember which version this changed but some lights (like point lights) were set to use half distance attenuation and some lights (area lights) to use physically based. It now looks like all are physically based which are producing darker results. (probably for consistency) If you change to half distance attenuation, you may get similar results to previous version tutorials.

2.5/ Also might be worth looking at Normalise Light Intensity to Area as I think this also use to vary per light type.

Rob

Thanks for the idea. When I add a light to the scene using the shelf tool it sets the light exposure to 5.15

It seems strange to me coming from Maya but the viewport and render view look correct now.

I'd still like to know what basis it uses for adjusting light exposure.

The exposure dial on lights is an alternate brightness scale that uses a familiar power of two scale, so adjustments can be made more intuitively. +1 is 1 f-stop brighter, -1 is one f-stop darker. The shelf tool sets the exposure on new lights automatically based on distance from the origin viewport pivot such that the inverse square fall off is exactly cancelled out.

“”“ Sets the light exposure such that brightness is 1.0 at the
viewport pivot, compensating for physical attenuation, if set. Does
nothing when scriptargs indicate that ctrl or cmd weren't being held,
since that means the light wasn't created from the viewport camera. In
that case we don't currently have a good estimate of the required
exposure.”“”

Volumes might look funny in the viewport for various reasons.

• Object level transformations are not applied when computing lighting.
  
• Inverse square falloff is not applied.
  
• 3D texture bit depth defaults to 8bit when switching desktops, which can cause the color banding as above.
  

Be sure to set the scene and texture settings in the scene viewer display options:
HDR on
3D textures: 16bit