Octane Render review

Tone Mapping

Octane’s interactive credentials are assured by a great feature that allows you to adjust the tone mapping of the render on-the-fly. Important parameters like f-stop and ISO can be adjusted either while the render is taking place and even after it’s finished. Using these tools you feel more like a photographer than a 3D artist, using the live view to frame your shot then adjusting the parameters to set your exposure, all in real time. Saturation, white balance, and vignetting mean that simple post-production can be carried out without the need to use an external image editor, or even re-render.

A downside of all unbiased algorithms is fireflies or hot pixels. These may disappear the longer the render is left to run, but Octane also provides a post-production filter that does a good job of reducing them if time is tight. Not that Fireflies are hard to remove in an image editor, but this is just one more excellent feature that lets you get the majority of the work done directly in Max. It’s also worth noting that the PMC kernel produced far fewer Fireflies in complex scenes containing mesh lights combined with specular and glossy materials than Pathtracer, and if Octane Render does implement Bidirectional sampling in the future we should see a significant reduction in hot pixels and improvement in speed.

Octane Render includes a large number of tone mapping response curves based on real-world film stock and, like all the settings in the Imager rollout, this is all achieved without interrupting the render. It’s a simple case of scrolling through the list of options until you find the look you’re after. There are currently no editable parameters to manually modify the tonemapping curves, but it’s easy to export the image using a linear response and using your own settings in an external image editing program.

Post Production

Bloom, Glare, and Spectral Shift complete Octane’s post-processing capabilities. Bloom is a simple, one parameter tool that produces some very effective results, Glare allows you to set not only the power but the number of rays, the angle and blurriness making it very flexible, while spectral intensity allows you to shift the resulting glare to create some beautiful effects. These are all of course interactive post-effects.

This short video demonstrates many of these features operating on Octane’s native Daylight object.

Camera

The Imager and Post Processing options are also available in the Octane Camera object. This allows you to create multiple viewpoints each with entirely different settings. If no camera is being used, the values will be taken from the render settings. It would be handy to provide an option in the Camera object to use the global values so that all the cameras in the scene could be coordinated. Currently if you are rendering out multiple viewpoints and you wish to maintain a consistent look, each camera’s parameters must be edited individually.

There are 3 camera modes available, all targeted and physically accurate. A standard camera, a cylinder camera and spherical camera. The latter is great for making interactive panoramas or quick studio HDRI maps. DOF is automatic and very easy to control using the the aperture setting, and there’s an option to easily render out anaglyph stereoscopic images with customisable filter colours.

Normal, Cylindrical and Spherical cameras

X and Y lens shift is useful to correct horizontal and vertical convergence for architectural renders, but it was a little tricky to get used to as you have to leave your camera level, then use the shift settings to pan around. The effects of these settings are only visible in the render, the viewports do not reflect the change, so the Octane Viewport must be used to frame your composition when using this technique. As fast as the render view is, it makes editing the scene difficult if the objects in the render are out of shot in the Max viewport, hopefully this is something that can be fixed in a future release.

It’s also possible to use 3DS Max’s standard cameras with Octane, though only some of the parameters are supported. This is helpful if you prefer a free camera or an orthographic view, since Octane’s camera doesn’t provide these features. Equally useful is the ability to use the multi-pass motion blur effect, though it’d be nice to see true motion blur supported natively by the renderer in the future.

Focusing the camera is as simple as picking a point in the render view, alternatively you can leave the camera to autofocus or use the camera target as the focus point. Personally I loved being able to just click an object from the scene and see it immediately come into sharp relief, especially when using a shallow depth of field. Using the camera in Octane is simple, fast and fun!