Nobody likes waiting for hours whilst their render finishes, but most people do. Little do they know, they can cut these render times in half with a little bit of tweaking.
By default, the big CPU sucking features are turned on default the blender devs want to ensure that you get the best looking renders. However when you are still working on the scene and don’t need to see the final image yet, it makes sense to turn these off.
Here’s a list of 13 ways to speed up your render times:
1. Turn off Ray Tracing
If you didn’t know this already, ray tracing eats CPUs for breakfast. It’s not uncommon for ray tracing to multiply your render times by 10. So if your project doesn’t need reflections, ambient occlusions or ray shadows then turn this CPU sucker off.
2. Lower the SubSurf levels
You might call this common sense, but when you’ve been working on a scene for 5 months it’s easy to forget that you created a car tire at the start with 6 levels of subsurf. Glancing over your scene and checking for any excessive subsurf levels can save you lots of time in the long run.
3. Turn off soft shadows
Sure it’s pretty but is it really necessary? If you don’t want to waste hours rendering, set the Soft size and the Samples for all spot lamps to 1.
4. Turn off Ambient Occlusion
Ambient occlusion is great for adding that extra touch of realism to your scene by faking indirect shadows. However it’s also notorious for stacking on hours to your rendertimes. If it’s not completely necessary, turn it off.
5. Turn on Simplification
One of the little known features in Blender is the Simplify option. This allows you to set global limits on subdivision, shadow samples and AO and SS so that you can quickly create preview renders. Definitely keep this feature close if you need to do a lot of testing and adjusting.
6. Turn off blurry reflections
A fairly recently feature is the ability to create blurry reflections. They certainly look pretty but be prepared to pay for that in rendertimes. By default blurry reflections are already turned off, but if you accidentally change the Gloss amount to anything less than 1 you can suffer the consequences of awful rendertimes.
7. Turn off Subsurface Scattering
If you do a lot of character modelling you probably already know this, but for those that don’t: Subsurface Scattering multiples rendertimes like crazy! Only turn this feature on if you are creating the final render.
A quick test revealed that turning this off could reduce your render times by 6 times!
8. Turn off shadows
If you aren’t rendering the final scene it can help to turn off the shadows whilst you are rendering previews.
9. Turn off Anti Aliasing
Another feature that can add hours to your rendertimes is the anti-aliasing option. Turned on by default, this option ensures that all the edges in your scene are smooth and unjagged. But if you aren’t rendering the final scene yet then turn it off! You’ll shave your render times in half!
10. Increase tiles
‘Tiles’ are the little boxes that you see appear when Blender is rendering the scene. Increasing tiles are recommended when rendering to a large size and need the CPU cores to render smaller segments. This will ensure that all cores work on the render until it’s finished without one core finishing before another.
11. Start Baking!
Everytime you hit render, Blender has to calculate all the shadows, ambient occlusion and lighting in the scene. If you are creating an animation it’s highly recommended that you bake all this data so that Blender only needs to calculate it once. If you don’t know how to do this, check out the wiki entry.
12. Make materials non-traceable
By deselecting Traceable in the materials section, you will make that material discarded from the ray tracing calculation. This has saved me HOURS of rendering time. If you have a complex object that doesn’t need shadows or reflections, then turn this off. You’ll be amazed at how much quicker your scene will render.
13. Reduce the dimensions
An obvious trick, but easy to forget. Setting the resolution percentage to 50% will render the scene 4 times faster!
Pretty simple hey? Hopefully these little tricks will come in handy the next time you need to render a large scene 
Do you know any other useful time savers? Share them in the comments below!
This is a lifesaver!
I have spend so much time waiting for previews. Not anymore.
Just have to remember to turn all this options on at the final render…
you can use pretty much all of them if you are only doing the preview of your scene
These are some great tips. I didn’t know about Simplification, and Tiles. I’ll definitely make sure to try those out.
Sometimes however, when it starts to get to the end of a project, and you are forced to turn a few things on, the render times can get pretty long. so I suggest taking a quick walk around the block between renders. There’s no reason to stare at your monitor, so go out side for a bit.
This is a life and time saver!
Thanks a mill Andrew, you definitly know blender like the palm of your hand.
Method 13:
You can always reduce another 5% there, it speeds up quite a lot. (We will squeeze as much performance as we can)
And you can only tell the difference when you shrink more than 10% in the dimension.
When doing simulations and animations, I like to set the render size to 10%. This allows for a quick render time, and I can see whether it looks like it’s working properly or not, even at such a small size.
Two other things that might be useful for test-renders:
Use borders (Shift+B) to select only a portion of the image to render
Use “Isolate Render Selection” (W) after selecting objects of interest to exclude all other objects from the render
Nice i did not try this yet
thanks
, but i was expecting more than that because these are already known.
anyways, aren’t there methods to use third party software
to increase the render speed, i hear they use GPU to render too !! using 3rd party software.
thanks though.
Hi,Andrew Price,
Thanks
Keep up your good work.
Accidently, I came to know your web site and your very interesting knowledgeable video tutorials.I already model a high rise architecture.I’m now working on kitchen interior tutorial.
I read your 13 point solution to reduce render time.I’ll apply these settings.
Thanks Andrew for this useful topic!!
Upping the tiles is a real time saver, could never really understand if increasing tiles would help until now. Thanks.
14. Use a CUDA or OpenCL based renderer like Octane
I think some of these were pretty obvious like Ambient Occlusion or sub surf or sub surf scattering. The rest was something I did not realize especially the ray tracing and the tiles.
well you didn’t splash your face over the internet with this one…
I’m sorry, that was just a joke.
Nice tips.
Just need to remember putting the settings back on when final rendering
Some time ago I made animation in Blender 2.49b. Here is a link if someone want to see it: http://www.youtube.com/watch?v=flgiCCt_x1o
Rendering time was terrible for me. About 10 – 16 hours per frame. But I installed Blender 2.53 and discovered Performance tab in Render buttons. There was 6 different Raytrace Acceleration Structures in Acceleration structure menu/list. I don’t know what differences are between them, but I choose BLI BVH. Rendering time dropped down to about 10 minutes per frame! There was no differences in image quality or I can’t see it
Thanks Andrew! This will definitely help.
Also, you can use GameBooster, TO STOP UNNECESSARY TASKS (processes) WHEN USING BLENDER so that you can have more RAM for blender when using Blender or rendering.
It stops tasks like: Messenger, Utorrent, the printer spooler, etc.
Those tasks are sometimes really not needed. Also, if your like me and hate Vista or Windows 7 (because they are resource hogging OS) and like XP, then you can also, terminate Explorer.exe to speed up Blender.
But, that part only goes if your low on RAM.
BUT SERIOUSLY GameBooster is a great software to download. Plus, IT”S FREE!!!
Thank you very much. Great advice
Here’s a good one:
Go into object mode
Hit “a”
Hit “delete”
Hit “f12″
Render time=00:00:00
great advice andrew, although i ended up finding a bug with raytracing, because when i started a animation render after a short time it turned my pc off, weird i know but i wont ever use raytracing again.
just out of curiosity with a simple scene say of the cube whats the render time dif between having all those settings on and off
Thanks Andrew, good pointers. One thing that popped into my head to improve render times … get a better computer! (Would be a nice lead in to an article on building a render farm or a ‘blender machine’)
Thanks Andrew ! That is very helpful !
Weird I’m rendering a scene and increasing the tiles for example in results in slower rendering ? Are there any limits on that ? I have an I7 so it isn’t the lack of horsepower I think
You know what is also good ? If you have a static background to render it to an image and compose it with composite nodes. I see a lot of people rerendering parts of a scene while the modeled background doesn’t chance.
I didn’t know about simplify, thank you!
I am completely surprised that no one has mentioned Environmental Mapping! Everyone! don’t use ray-traced reflections, just use environmental maps!
Regarding #10, does increasing the tiles have much of an effect for those of us that are still stuck with single core processors? There have been instances when I reduced the tiles to 3×3 and saw an increase in render time, and I’m wondering if that could be why.
Tansunn, increasing the number of tiles will significantly reduce the amount of memory needed while rendering (but I think it doesn’t apply to ray-tree building stage), but usually doesn’t have such a significant effect on speed be it single-core or multi-core.
I know more one Andrew! Camera limits!
Nice Tips!!
Some of them already known, but some new….Always interesting!! (Render Time is a pain when trying to achieve realistic results)
I’ll print them out as a reminder, so that I don’t forget to turn them on before final render….
One suggestion (not ever tried): “Render Farms” are clusters to share render power of machines… (Google it!)
if you want to render an animation and you think it will take you days to render it is always good to check out a free cloud rendering service like renderfarm.fi or vSwarm
Material override in the layers panel, to place lights and preview animations with a simple default material.
Or use SmallLuxGPU when it’s ready… Btw. nice Audi model by Andrew Price!
http://vimeo.com/14290797
Nice tips. Good for preview stuff. Final rendering is another story. Using GPU renderer is a real time saver for that. I also suggest using composition nodes more often. You need to render static background only once and composite it with animated foreground later for instance.
One of the methods I have just started to use – is when something is animated such that it is no longer in the render window, add an ipo curve that will change the objects layer to one that is not rendered. For example, I am working on an animation using the techniques Andrew showed in the shattered glass tutorial. In my case, there are three objects that will explode. The first, and biggest object has all of the particles out of the camera view at frame 300, at which time the next object begins to emit particles. By changing the layer of the first object at frame 301, the remaining frames render much faster.
I’ve found that #12 is VERY good to use on a ground plane. Those things almost never need to be traceable, and they’re usually so large that it significantly changes the render time.
Hey Andrew, this will be useful for future work.
By the way, you may want to check the paragraph under the title. Sounds a little funny. Oxymoron…
Anyway, see you later.
-AE
thanks Andrew!!
Very useful stuff! thanks Andrew. You can also include removing rendering of entire objects in complex big scenes with lots of stuff. That way you don’t need to render all the little things if you just wanna focus on something bigger.
What would really be nice is if some of those settings were included in a render preset. Unless I’m missing something, the only thing the presets change is the image info, size, frame rate, and quality.
One could just create their own preset called “Test Render” and use it until the final render.
re: #10,
Increasing the number of tiles does not always reduce render time. This is dependent on other factors.
http://wiki.blender.org/index.php/Doc:Manual/Render/Options#Parts_Rendering
13 ways to make a preview rendering faster.
your title is a little misleading to be honest besides
2 tips which can also be used for finale rendering.
I have a question that’s more counter-intuitive to this feature. How can I get the best quality render (i.e. anti-aliasing, HD video quality, etc.)?
Thanks a lot!! (^.^)
Very useful article.
Hey can you write one on baking?
A simple article so that commoners like us can understand the basic theory behind it?
Thanks for the tips. Bookmarked the page
Lets hope for render presets in Blender, so the high/low settings can be changed on the fly.
Haha, sometimes I wait for half an hour to get a 200% render. I just love high quality!
Great tips Andrew,
What if we could set up different render presets like:
* Quick preview
* Medium quality (with shadows)
* High quality (with shadows, raytrace and so on)
so we quickly could switch between then when needed.
That would be quite time saving.
I agree to point 11, but only if you have static objects and only the camera moves, otherwise shadows and reflections change continuously and you can’t bake it.
yep, iam curious to experiment this feature. regards
BlenderGuru should have a ‘like’ button, nice post!