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By default, every object in your scene is considered to be opaque. There’s a very good reason for this, it helps speed up renders considerably. But if you’re new to Arnold, you may have found yourself scratching your head when trying to render transparent objects.
Setting up transparent objects in Arnold is easy:
An alternate method is to use the 3ds max Physical Material. It translates to Arnolds "standard surface" under the hood, but does manage things like the opacity flag automatically.
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