Tips for more realistic Renderings in Blender

In this article, I want to give you some Tips at the hand to get more realistic Renderings and also explain why you should use them and what they actually do, to give you some deeper knowledge.Everything here can be applied to CG in general, but it is written specifically for Blender.

25/02/2022|In 3D|12 Minutes

Use HDRIs!

HDRIs or Spherical Images, how they got called, are images that get wrapped around a 3D scene to light the Scene. The benefit of using HDRI lighting is, that it brings a lot of details with it which is the reason, it makes the render much more realistic and on top of that, it is quick and easy to set up.

You can also supplement the HDRI lightning with some additional Lights if you want to brighten up a specific are a for example.

Since HDRI means High Dynamic Range Image, images with a higher Dynamic Range should be used, this can make a huge difference even if you don’t export your images in a High Dynamic Range.

You can recognize images with a high dynamic Range by their format. Formats like Radiance HDR, OpenEXR, TIFF and some other formats can contain HDR Images while Formats like JPEG or PNG can not.

To everyone who wants to create Studio light, I recommend the Blender Studio Light Add-on. It is a free Add-on that allows you, to create your HDRIs within Blender by using images of real Lamps which, like normal HDRIs also give you the advantage of the extra detail to create more realistic Renderings.

Bokeh

By using the Depth of Field feature which you can find in the Camera Menu you can create Bokeh which not only makes your Image more realistic since it emulates something which is happening inside a real Camera.

It also gives you the possibility, to hide things you don’t want to show, like parts with fewer details or seams in the texture. Because let’s face it, you can’t create everything with high details because it would take waaaay too long.

Another benefit of using depth of field is that it enables you to guide the viewer’s eye to a specific place.

little girl on a hourse of a carousel 3d animated

Bevels

If you take a look around you, You won’t see many objects with sharp edges. There are some exceptions, like sharp or really thin objects. But these are just exceptions. And making something look realistic means making it look like it would in reality.

Also, If you create some more abstract motion graphics, this small light Edge can enhance the final result.

Motion-Blur

Motion Blur is in every Photo or Video, sometimes it is so little that it is invisible or only gets recognized subconscious, but technically speaking it is there all the time. Which is the reason I recommend using it if realism is your goal.

To activate Motion Blur, you just have to tick the box that says Motion Blur, which you can find in the Render Settings.

Of course, you need to have a moving object in the Scene to see Motion Blur. If you have a still image, just animate the Camera a bit.

The default options should be right most of the time, but I still explain the settings to you.

Shutter

The Motion Blur is a build-up of two effects, the first one is called Shutter. Which in real life happens because the Camera captures the light through a small period of time. Usually the half-length of a Frame. This means if you’re filming with 24 Frames per second, the period of time in which the light hits the sensor is 1/48 second. With 25 Frames it is 1/50 second, with 30 frames it is 1/60 and so on.

The longer the time is the light can hit the sensor, the more Motion Blur you will get and vice versa. You can set the amount of time the light hits the sensor per Frame with the Shutter Option. Which is by default set to .5 which means how I mentioned the half-length of a Frame (24FPS 1/48s, 25FPS 1/50s, 30FPS 1/60s…) Which is the setting most cameras also have by default. You can also change this to 1 for Example which would mean the Light would hit the sensor the complete Length of the Frame which means 24FPS 1/24s, 25FPS 1/25s, 30FPS 1/30s…

You can use this if you want to combine Video and CGI and you had another Setting for the Shutter in your camera, but most of the time 0.5 will give you the most aesthetically pleasing results.

Screenshot of Blender 3D Software Motion Blur Settings

Rolling Shutter

The other Effect is The Rolling Shutter. The reason, that this happens in real life, is that the camera captures the Images in Lines from Top to Bottom. This happens quickly but not at the same time, which is the reason you can see it when it comes to fast-moving objects like cars or planes. It also happens with fast camera swivels.

In Blender, you can activate it by selecting Top-Bottom for The Rolling Shutter, which is currently the only option. You can set the strength with the Rolling Shutter duration, but also here the default settings will do their job most of the time.

Also, if Rolling Shutter gives you more realism, you should ask yourself if you want to use it because it is less aesthetically appealing compared to the normal Shutter Effect.

Reference Images

Since we try to remake something what’s already existing, at least until a certain degree, it makes sense to orient somewhere. Also, If you know how an Object looks it always makes sense to get reference images because most of the time it is a bit different, then we remember.

Getting close to a real object can make a big difference because to recognize something the basic shape often is enough for our brain to reconstruct the rest.
For example, you probably know, that I this bottle is no water and some people would even know which brand this bottle is from.

To organize your reference images, there is a helpful and free Software called PureRef. At this point, it also can be helpful to have a second screen.

Imperfections

In the real world nothing is perfect, every surface has unevenness, scratches and dirt on it.

Ideally you use a Reference Images to see, where things wear out and where the paint comes off first.

But don’t overdo it. The model should fit inside the scene and inside the story you are telling.

Denoise

Image with alot of Noise

The type of noise you have in your render if you are using a low sample count is a different type of noise, then what you would see if you would use a Camera, which is the reason it makes sense to remove that noise.

Blender offers plants of options for that.

If you want to have film grain inside your Images or video, there are a lot of options to achieve this in Photoshop or After effects.

Personally, I am using the Nik Collection in Photoshop and Magic Bullet Looks in After Effects.

Enough Lightbounces

In reality, light bounces around a couple of thousand times. The problem is, that this would eat up too much computing power which is the reason, you can set the number of light bounces in Blender. By default, the Maximum bounces are set to 12 which is enough most of the time.

But in some cases it can make sense, to use higher values especially, when it comes to Glass materials.

Screenshot of Blender 3D Software showing a problem wit Light Bounces

In the picture, you can see the light only coming through the first three plates of Glass. The reason is, I limited the Maximum Light bounces to 4. But also if it is most noticeable with Glass, it can make a difference with any other Material, especially in more complex Scenes.

You can change the Maximum Amount of Light bounces in The Light Paths Menu in the Render Settings.

Screenshot of Blender 3D Software Showing Lightpath Settings

Not only use Principled Shaders

Screenshot of Blender 3D Software creating a Material

Also, if the Principled BSDF Shader can be really usefully and enables beginners to have more realistic materials by default, the possibilities of the Principled BSDF Shader are also limited. And I have the feeling, that since the Principled BSDF Shaders got introduced, beginners stopped looking at the other Material options that Blender offers.

So I want to encourage you to take the time and create nice and complex Shaders. A Good examples for someone who does this is String Fairy.

Do post processing!

Post-processing is something which not only can make your rendering look better it can also can make your images more realistic by emulating effects, that the cameras are doing like lens distortion, adding Grain, adding a Vignette and so on.

Try other Render Engines

Rendering made with LuxCore Render with Bidirectional Engine

Cycles is good in most scenarios, but there are Scenarios in which Cycles performs not that good. The best example are scenes with a lot of Glass, Water, or similar Materials because Cycles is bad at creating Caustics (which is the bright point on the right that you can see in the image above, that I rendered with Lux Core Render).

Compared To the Lux Core Render Render Engine, which is probably the best Blender compatible Render Engine for physical accuracy.