the right lighting for photo match with sketchup

[lape]

For my next project I need to use photo match with Sketchup. I have a photo of the real environment, where I want to place my model. The problem is: how do I get the right lighting?

In Sketchup, I can add the date and time of the photo, so I get the right settings for my shadows. But on my photo there is a sky with some distant clouds, the sun is only very weak. When I use the Indigo sun and sky options, shadows fit perfectly, but the color and itensity of the sun is much too strong, because the sun was weakened by the clouds.

What would be the best way to simulate the light from the photo? Is there a possibility to reduce the sun intensity?

[Zom-B]

Showing the Photo could help here

In Full Indigo version you could use LightLayers and simply reduce intensity of sun layer.
To get that done in Indigo RT you need to do the following:

- set your sun the way it fits the scene.
- Now place a camera in the XYZ center of your scene, and deactivate all meshes.
- Now render that scene with spherical cam and save the resulting HDRI as EXR file
- Open the EXR in your favorite image editor and dim the sun sphere by painting over it or whatever
- You can also blend that clean sky + Sun Hdri with some other HDRI (where you paint totally over the existing sun) to get some clouds etc.
- painting a new little bigger Sun can create softer shadow edges that can be needed for a cloudy scene

[cotty]

Two problems with this workflow:
- No HDR output with Indigo RT
- Spherical camera not available in SkIndigo (yet)

Edit: some older hints for equirectangular environment rendering can be found here

[lape]

Thank your for your replies!
Seems I need the full Indigo version... Next time it would be useful to take a hdri panorama with my camera. I have a multirow head and ptgui, so this would be no problem... unfortunatley it's to late for the mentioned project

[Zom-B]

- No HDR output with Indigo RT

Oh, I totally missed that -.-'
So my "HowTo" fails in the earliest stage...

- Spherical camera not available in SkIndigo (yet)

simply start rendering with a usual camera and then change it to spherical in the GUI

[StompinTom]

- No HDR output with Indigo RT

Save a series of regular JPGs or PNGs at different exposures and merge them in Photoshop

[cotty]

simply start rendering with a usual camera and then change it to spherical in the GUI

I've always searched this in the render settings and never opened the property editor for the camera until today... GREAT TIP! Thank you!