Rendering in Blender 2.8

This is a quick walkthrough on how to get your beautiful Blender models into an image or movie to share with the world.

Step 1: Choose your engine

Ideally do this at the start of your modelling process, as the engine affects some of the materials and effects you can use.

Blender 2.8 has 3 built in Rendering Engines. We will focus on 2: Cycles and EEVEE.

To change the engine, in your properties window choose the ‘Render’ tab and select from the Render Engine drop down

Cycles

Blender’s long-standing ray-tracing engine is great for rendering photorealistic scenes where realistic shadows, reflections, and refractions are important.

Cycles requires many samples to create an accurate scene. As such with Cycles you need to trade between time and quality: a high-quality render can take a lot of time, a shorter render can look very grainy

A low quality cycles render: quick but grainy

EEVEE

EEVEE is Blender’s new ‘real time’ renderer, meaning that the feedback on what your scene looks like is real time. The trade off here is that there are plenty of physical inaccuracies: shadows are estimated, reflections and refractions don’t work well, and tthere is no ‘Global Illumination’ (i.e. light emitted from objects does not fully affect other materials in the scene).

However, just because EEVEE does not use physically accurate rendering does not mean that it looks bad. EEVEE has all sorts of tricks to make your scene look good (and quickly too!).

Step 2: Render Settings

This step assumes that you have already created a scene in Blender you wish to render out.

Whether using Cycles or EEVEE all the settings we need to adjust are in the top two tabs of the Properties panel. The first tab covers settings relevant to render quality (which differ across engines), and the second covers settings relative to the output file (type, size, location)

The tabs are called ‘Render’ and ‘Output’

Render Settings: Cycles

Cycles Render Settings

Cycles has a number of intimidating settings, and most of them have a meaningful effect on the image quality. I’ll cover what’s necessary to get you started here, but I recommend playing with the settings to get a sense of what they do.

If you have a CUDA enabled NVidia GPU you may be able to use that to speed up your render under ‘Device’. If not, you’ll have to stick with CPU.

Sampling

The number of rays sent out per pixel. The higher this number, the less grainy your picture will be. Higher numbers take longer to render.

Light Paths

Max Bounces refers to how many times a ray can bounce off a material before it is cut off. Higher numbers mean a more physically accurate scene but also require more rendering time. For rendering simple scenes the default should be more than enough. You can ignore clamping and caustics for now.

Performance

Threads help decrease render time. Leave on auto-detect to use the maximum number of threads your system can handle.

Tiles refers to the size of the ‘chunks’ of an image cycles renders at a time. Large tiles can be memory-hungry, so the best settings here depend on your system.

  • A capable GPU can handle larger tiles (try 256 or 512) which will speed up rendering times.
  • A lower GPU or plain CPU may need lower tile sizes, around 64

The best thing to do here is test your system with a variety of tile sizes on a large scene and make note of which setting is fastest.

Volumes

Ignore for now. Important when using volumetric lighting.

Hair, Simplify, Motion Blur, Film

Advanced settings to ignore for now.

Render Settings: EEVEE

EEVEE Settings

Sampling

EEVEE also uses samples, but they are a lot more forgiving than ray-tracing samples. I’ve found that I can get away with very low samples (<12), unless I’m adding special effects or complex scenes.

Ambient Occlusion

Ambient Occlusion is a way simulate the way light interacts with corners and holes. Generally corners and holes receive less light than exposed areas, so should appear darker in the scene. I’ve had mixed results with this setting.

Bloom

Simulating camera glare effects popular in the Star Trek 2009 reboot, Bloom adds a sort of glow around bright objects in your scene. I use it as a cheap way to add a little cinematic flare to a scene.

Depth of Field

Settings for camera depth-of-field. Not super relevant at a beginner level, but can be used for great effect!

Subsurface Scattering

Leave alone unless you have special subsurface materials

Screen Space Reflections

Since EEVEE does not inherently render reflections, this effect is a way to estimate reflections in the scene. For some scenes it works great, but requires you to have reflective materials (such as a ‘metallic’ material).

Quality is affected by Sampling setting above.

Shadows

Increasing the ‘Sizes’ of the shadow resolutions will help you get shadows that look a little crisper. Especially in large scenes EEVEE’s shadows can appear a bit blocky.

In addition, selecting soft shadows will help blend shadows into the scene a little better (at the expense of a hard shadow penumbra).

The Rest

The other settings are situation specific, and in general not super necessary for getting the hang of EEVEE.

Step 3: Output Settings

Regardless of Engine, you need to tell Blender some stuff about the file you want to make. You do this in the Output tab of the Properties panel

Dimensions

If you just want a still image, the Resolution x and y are the important settings (and make sure % is at 100).

If you want to output a video, then here is where you specify the framerate and also the number of frames from your timeline to include.

Output

In one of Blender’s most confusing UI choices, this tab will affect animations only. This will not affect how single images are rendered. Set up the directory and filename that you want to save your video file, and choose the video format here.

My recommendation is if you are exporting for video, choose an image sequence (e.g. PNG) rather than single video file, and stitch it together in another video editing program (DaVinci Resolve is also free).

Step 4: Render And Save!

Preview

If you’d like to preview how your render will look, you can change the viewport display mode to ‘Rendered’ in the top right of the 3D viewport. In EEVEE this should provide instant feedback, Cycles may take a moment to resolve.

Viewport mode: Rendered

Render Image/Animation

In Blender’s top menu there is a ‘Render’ tab. Click than and choose whether you want to render a single image (the current frame) or an animation (according to ‘Output’ settings above).

If you choose ‘Render Animation’ the files will save to where you pointed above. If you choose Render Image then there is one more step below.

Save!

After you click Render Image a new window should open with your image (in cycles you will see the rendering progress). If you don’t see the render window click ‘View Render in the render menu.

In this new window, under the Image tab, you can finally save your image!

That’s all folks.

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