Dome light and HDRI and soft shadows

[gnassbasti]

Hi everyone,

I couldn't find anything on it so far and hope anyone can help here:

I am using Vray 3.6 on Maya 2016 for my renderings.

While rendering an arcitectual exterior scene using a dome light and HDRI I am always getting sharp shadows, and can't find a way to get them soft.
While rendering with Vray sun and sky, I am able to soften the shadows by increasing the size multiplier of the sunlight.
When using the dome light and a sun or directional light on top I get double shadows. If i deactivate shadows from the dome light and only use the shadow from the sun light, the image doesn't look right as I get brightness from the domelight but no shadows.

Watching tutorials on youtube this issue never gets mentioned, and it seems no one else has problems with it.

Am I missing something? Is there a way to get soft shadows while rendering with HDRI?

I would be greatful for some tips!

Thank you.

Sebastien

[Buck]

If you want soft shadows from an HDR that has a small point light (like the sun), you'll need to blur the HDR file. You might be able to do this in Maya using the filtering on the image. In the file node, under "effects", start raising the filter. Maybe try like 50 or higher, depending on how soft you want it. I've not tried this on a dome light, but it does work in an area light.

I don't know that the quality of blur will be very good, you'd have more control by actually blurring the HDR in Nuke, photoshop, or whatever else.

And if you want to have sharp reflections and soft shadows, you can use two dome lights. One that is diffuse only (your blurred HDR) and then one that is for reflection & spec only (sharp HDR)



The other option would be to paint out the sun from your HDR, now your HDR is basically an ambient fill light because the bright pixels from the sun aren't there anymore. But all the rest of the color and brightness for the rest of the HDR are intact. Then you could use a sun light to control the direct light.

[gnassbasti]

Hi Buck,

thank you very much for the reply and the tips! Raising the filter in the file node unfortunately does not work. The rendered environment blurs but the shadow does not change.

However, bluring it in Photoshop works great. Using two dome lights (one for diffuse and one for reflections ad spec) works perfectly too.

Thanks again!