Here are some tips and tricks I've been picking up from websites in order to teach me how to use sketchup/ indigo/ photshop.
Environment
Turbidity: The turbidity defines the haziness/clearness of the sky. Lower turbidity means a clearer sky. Should be set to something between 2 and ~5.
Extra Atmospheric: Removes the sky and renders only the sun. Good for renders in space
Extra Atmospheric: Removes the sky and renders only the sun. Good for renders in space
Illuminates scene with an HDR environment map. Indigo can load two types of HDR environment maps, an .exr, and a .float map in spherical format. .float is a simple format exported by the HDR Shop program. You can define the . map's width, but it must be equal to its height.
Gain: The map's brightness is scaled by this factor when it is loaded.
HDR
An HDR environment map is an image that fully wraps around your scene to create the effect of having a background, and also emits light. It is important that you use an HDR environment map that has good light, especially if it has the sun in it – the sun is many thousand times brighter than anything else and will only cast good shadows if it has been captured right. This technique gives the best results because all the reflections from the materials will accurately respond to the 'environment' as if it were real. But it is difficult to find a good HDR environment map for free – and can be difficult to make your own. I am using an HDR environment map found from openfootage.net
Download an .EXR or .float HDR map. Indigo does not support .HDR files, but there are good converters out there. Try Picturenaut.
Depth of Field
An image is always sharpest at the cameras focal distance, but the depth of field is controlled by the camera's aperture, measured in f-stop. The smaller the f-stop number, the smaller the depth of field; the larger the f-stop, the larger the depth of field
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