You are working on a 3D animation task and the deadline is in 2 days. You have done all the modeling, texturing, lighting, rigging and animation and also currently its time to render your last output. You put up your render and also it indevelops you that your sequence of imeras will certainly be ready in 3 days.

You are watching: Why does video rendering take so long


What’s going on here? Read on to learn why 3D rendering takes so much time and also what you have the right to execute about it.

In basic terms, the factors for 3D rendering taking so lengthy is its a memory intensive procedure, your computer specifications may be low, and also you might not be optimizing all of the things in your 3D scene, your render, and also your output. However before, tbelow are more than a dozen other determinants to take into consideration as soon as trying to figure out why your 3D rendering is taking forever before. We will certainly acquire right into every one of them however let’s start via the basics of just how 3D rendering actually works.

3D rendering is the process of developing a 2D picture from a 3D scene. Its kind of favor taking a photo of the genuine human being, except its a online people. If you are rendering a movie, it may be a sequence of still documents favor .tiffs or one movie file such as a .mov, .avi or .mpeg. An individual frame in a movie may take a 2nd or several days to render, based on many factors.

Now let’s discuss this in information and also then take a look at possible workarounds.

Factors Affecting Rendering Time

Computer Specs

Its true that the amount of computer power obtainable to us appropriate now via multi core processors and numerous RAM is literally 10s of countless times better than 30 years ago. But as I point out later, we have checked out an increase in picture format output and top quality demands and viewer expectations.

CPU speed helps through rendering time. So does the form and variety of GPUs if your mechanism is capable of using them for rendering. In basic, the greater the computer specs the much better it will certainly be for rendering. Tright here are many workstations especially designed for 3D work, however rendering the actual output conveniently has actually its own requirements which a workterminal might or might not completely accomplish. More around this later.

Let’s look at components that the majority of add to rendering times.

Photorealistic Rendering

A photorealistic render of a solitary framework have the right to take days depending upon the information and settings associated. When you multiply this by 30 frames per second for movies you acquire some staggering numbers. As the name argues, such images come cshed to real life and this needs eincredibly detail to be perfect. Shortcuts below would certainly really stand also out. If you are doing photorealistic rendering on a huge range rendering time will certainly be an concern.


Computers use miscellaneous methods to geneprice each picture, or still structure in a movie. One of them, raytracing, is a slow process. To make things really easy to understand also, it simulates actual light rays from light resources that hit the camera. This provides your 3d scene act favor the genuine people, and to those familiar with 3d animation and also how its produced it renders perfect feeling. We are simulating actual phenomena such as light rays in a “real world” 3d scene. Not surpisingly, playing God is memory extensive.

Reflections and also Refractions

Speaking of memory intensive procedures, reflections simulate how light rays bounce off surencounters and refractions exactly how light rays go through surfaces. We are playing God aobtain considering that we want the resulting imeras to look like the outcome of actual world physics. Bouncing lights rays approximately the scene likewise requirements to be optimized for output. You deserve to shed most rendering time if your rays are getting shed or if you collection things approximately usage as well many kind of or the choices are simply not set optimally. With experience and virtual or book study you have the right to grasp this, but its additionally certain to the render you usage so consult its hand-operated.


Tright here are generally two types of shadows in a 3d program, depth map and ray traced. Depth map shadows are a lot faster to render but come with their own concerns, such as resolution and also artifacts. Basically a depth map is developed from a light to each shadow spreading object. Depth map shadows deserve to be modified to proccasion artefacts and also still administer a great high quality.

Raytraced shadows on the other hand also are not precomputed; they are rendered one pixel at a time in the time of the actual scene rendering procedure simply favor other raytraced items. Be incredibly careful about utilizing raytraced shadows. Even film production residences use depth map shadows.

Output Resolution

This is widespread feeling to many type of yet lets go via it to make sure we understand also. Required output size has actually grvery own over the years from 720×480 pixel conventional interpretation video to 4k (4,096 by 2,160 pixels) and also 8k (7,680 by 4,320 pixels). Imeras via better resolution take longer to render considering that its done one pixel at a time.

Of course this doesn’t have actually as a lot of an result if we are talking web 3d animations consisting of animations for 300 pixel wide banner ads, however the internet is recording up. With monitor sizes getting bigger and better resolution, and civilization currently projecting their web content onto 80 inch tvs and 100 inch estimate displays, the output requirements for the internet are transforming also. While screen dimension and also display resolution are 2 different things, if you keep resolution the same and also increase your screen size by a far-reaching amount your image will certainly shed information.

Physics Engines and also Dynamics

Physics based animation is a good means to rate up your occupational and make realistic motion, whether its blood cells in a capillary or fluid simulations. However before, since the computer system has to calculate all the collisions, and periodically there are thousands in a scene, rather of you animating by hand, much of its computer power is supplied up below.

How To Shorten Render Time

Now that you recognize what is associated in producing a 3d animation or 3d still and also see how memory intensive it is, lets look at some methods we deserve to resolve this concern.

3D will constantly be 3D (and we are glad bereason it helps us develop a real-choose world) however its a lot more complex than 2D in regards to calculations. Also, in 2D animation, the human is the one who draws much of the piece by hand also, even if utilizing automated inbetweening done by the computer system.


Keep in mind that as soon as a render starts, the regimen looks at every little thing in your scene, from nodes to models to textures to shadows. If your geometry is hefty and also your 3d scene is slow-moving to pack and also navigate with, possibilities are your rendering will certainly endure as well. So try to optimize your scene. I supplied to be a perfectionist through my 3d models and also make them high detail anywhere.


The method that will certainly conserve you rendering time is to focus on what will be in the frame. People have gone as much as deleting components of a design that execute not challenge the cam for the certain file to be used in rendering for this reason. If you are working with subdivision surdeals with you can reduced the subdepartment level.

Look through your scene and also see if tbelow are any type of models you operated on for a lengthy time that you have included a large number of subdepartment levels to. With polygons there are miscellaneous approaches depending upon the software program of bringing the variety of polygons dvery own as much as its still acceptable for viewing.

Also, plan ahead- when a things will certainly be far from the electronic camera or not in emphasis if you use a shallower depth of area, you have the right to pay less attention to its detail, shadows, reflections, etc.


Subsurconfront scattering is excellent for making character skin look realistic. But it likewise adds a totality lot of time to render. See if you really need it, specifically for long animations, and also if you have to store it on, leave it off till the final render.

You can use textures fairly than polygons to make the scene lighter, especially if the version is not exceptionally close to the camera and does not need to be detailed.

Baking, relying on the software application, have the right to be done on textures, shadows, lighting, ambient occlusion, and so on Bake as much of these as you can before rendering to rate points up for an computer animation.

Command Line

Also, uncover out if you can batch render your scene from the command line. You deserve to execute this in programs favor Maya. That means your open up 3d regime will certainly not be making use of a lot of your mechanism resources while rendering (and trying to present you each new frame in a viewport). Instead only the rendering component will certainly be open up and also active.


Raytracing can be turned off totally which would certainly save you a huge amount of rendering time. This all counts on your current project and whether you really need to usage refractions, reflections, ambient occlusions and ray shadows. Think of just how you can job-related roughly these.

I mentioned optimizing your raytracing. You desire to look into alternatives such as the variety of max steps, which will decrease the variety of bounces of a light ray. The number of bounces itself deserve to be managed. The more bounces the even more realistic the scene yet you can balance this in between perfection and also speed.

Shadows take time to render, particularly ray traced ones. If you need them save them off until the last render.

Gamings usage a trick for actual time rendering (not for prevideotaped animation sequences that are done the sluggish way) which involves rasterizing where distance and orientation from each surconfront to a light is calculated, rather than bouncing actual light rays anywhere the scene, also where they cannot be watched by the viewer.

Turn off your ambient occlusion unmuch less its absolutely vital. Sure it provides things look more realistic however at what cost?


Get yourself some faster hardware pardner! In all seriousness, it might be time to upgrade your computer to somepoint prefer 12 cores and 64gb of RAM.

Even with multi core processors, rendering times can be boosted if you usage many kind of CPUs, so a render farm with thousands of CPUs have the right to be of advantage to you. With the development of cloud computer, this distributed rendering has obtained even much easier (and also faster).

On the topic of cores, make sure your rendering software program is making use of every one of them. You would certainly be surprised that many kind of times for whatever before reason it is not. Check your rendering software program alternatives for this.

Some 3D rendering devices assistance GPU rendering as opposed to CPU rendering. Check this with your software program maker as GPU rendering deserve to rate up your rendering times. You deserve to also use multiple GPUs installed in your mechanism.

Hard disk performance and connection is an worry also. You do not want to be rendering to a USB 2.0 non powered low rpm portable drive.


If you have actually scene via dynamics/physics associated, you might desire to bake the animation out to keyframes prior to rendering. Consult with your software application manual.

Render Settings

Are you making use of movement blur in your animation? Depth of field for realism? Are they essential for this particular scene?

Think about what renderer you really need for a certain scene. Do you require psychological ray or will certainly a consistent renderer or probably a toon renderer suffice? Tbelow are many developed in renderers and plugins, depending on your 3D software program package. New render plugins appear on the industry all the moment promising faster render speeds.

See more: Which Of The Following Is Not An Example Of European Supranationalism?

Below is a video clip on increasing your 3d rendering using GPUs:

I hope that this short article assisted you understand why 3D rendering is such a time consuming procedure and also the tips above gave you some concepts on just how to shorten your rendering time. Thanks for reading.