Houdini Isn’t Scary - Part 5: Rendering

Welcome back to Part 5 of Houdini Isn’t Scary, this part is the continuation of the donut rendering part. We are finishing off the render settings needed for rendering our donut. This means that we’re covering ROPs as well as Motion blur, Velocity blur and how to actually save out an image from Houdini. When we ran our sprinkles through the DOP network, we generated velocity. That velocity can be used to blur our sprinkles as they fall. To do that, we need to activate our motion blur in two places: Firstly, on the sprinkles object. And, secondly, on the render node in our /out network. Next we activate depth of field. Depth of field is the blurring that you notice in an image when things fall in and out of focus. At a larger scale, depth of field is less noticeable but as we move to smaller scales, the amount of blurring increases. For the most part the blurring is controlled by the scale and by the f-stop. If you’d like to understand f-stop in real life (and by association in Houdini), here’s a great art