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!
Have to print this page and put it side by side with the BlenderSheet so dont forget to turn all on
@Morten
Andrew, thanks for this great guide! It will help me in the long run.
However, I noticed that you made a slight error. Increasing the tiles does not decrease the render time. It dramatically increases it for me. I took your realistic fire tutorial and rendered it in 8×8 and it took 2:00 minutes flat. then i took it down to 2×2 (tiles) and it took a whopping 50 seconds less! (1:10)
Just sayin’
It was just yesterday I was searching for some tips to make fastest renderings… and then your awesome post appeared!
Really thanks !
Now that you mention it. A baking tutorial would be helpful. The concept still confuses me. I think that somehow it reduces the render quality (to bake?)
baking is basically just pre-rendering that only needs to be done once that save time in rendering because your computer doesn’t have to recalculate it evey time.
wow, nice! I did not know about the simplification! Really a helpful article!
Nice Thanks a lot
#14 turn off your computer ; )
its ridiculous how many things you have to disable in blender to get proper render times. You can do complex stuff such as sculpting with blender but if you want simple reflections you are back in the nineties..
- untick subsurface scattering from the scene tab, it takes precedence over individual material settings.
something that has helped me reduce render times is being able to “region render” using shift-b in camera view. untick the border option in the scene tab when done. region render is great for testing local changes at their eventual resolution without having to render the entire plate.
thanks Andrew,
how about a render command from the shell/terminal? I think u should mention it too in this post.. i haven’t test it yet, but logically it should be faster than rendering with GUI’s
Yes that is true. Baking will help a lot. I once did a project and on my PC I had then took 1h 15 min per frame and after baking the walls, floor and roof nokked it down to 15 min.
But agan oy can only do it with objects that doen snot move or have any reflections on it.
I was confused by step 11, “Start baking”, where it says “If you are creating an animation it’s highly recommended… ”
In the Wiki it says “If shadows are baked, lights and object cannot move with respect to each other.”, so surely that means it’s no good for animations? I haven’t experimented with this since the UV unwrapping would take me ages, so apologies if I’m talking nonsense!
Also dont forget for testing specific parts of your scene, you can do partial renders using the box tool in camera view.
Whoops! Just noticed, dealga beat me to it lol
wow, thank you very much for this, Andrew
I have a big project in progress, and the render tests take forever… definitely bookmarking this 
Awesome list – for those who’ve been around for a while, not much news, but still a good refresher. Too bad we can’t have our cake and eat it too – fast times with all the eye candy turned on!.
Well Stan it might be true that Blender’s internal renderer isn’t the fastest but noticed how much faster is the new renderer in 2.53 beta.
I’m getting rendering times somewhere between a third or a fourth of the time on average for most scenes compared to what Blender 2.49b used to take and in some cases it takes even less.
I take for example a scene that used to take me 33 minutes in Blender 2.49b and I open it as it is in Blender 2.53 beta and render it in there and the render time is reduced to 8 and a half minutes. That is not a small improvement, that’s huge.
At least they are trying to make it faster and they have to be acknowledged for that and that was quite a change and we are almost there into a full production ready Blender 2.5x were we will be able to use all its tremendous improvements.
Some1 please answer my question(if you know anwser).
Is there any script in what i can export blender projects for
cinema 4d or 3Ds Max?
Some1 please help me?
If there is,please send me the link!
Thats great hints!!
Maybe you could expand this on a bit looking into techniques that allow to split up scenes for anmiations. Cutting the cheese in the background.
Like separating background and foregrounds for animations. So one could get away with rendering stuff that changes while using backdrops for distant detail that are stable anyway. I sometimes imagine that like they do it in the movies using mockups in the back that is out of focus anyway.
@anon go to blendercookies.com you’ll find baking tutorial
There doesn’t seem to be a background image setting in blender 2.53 Beta, any one know how to get it?
I use it for making cars in blender, but since I can’t find it, I use blender 2.49.
@ André Jordaan
There is a background image setting. When you press the “N” key, use the scroll feature on the window on the left and it will be close to the bottom, you can’t miss it.
Anyway, this was a very helpful article. I’ve got a mini project started and this has already helped me out tonnes.
Could we translate this tutorial in Spanish ? quote and named the author and the references links¿?
You could also tweak around the Acceleration Structure settings under the Performance tab, which is by the way, new in 2.5 series. So far with my understanding, this has something to do with Blender’s way of calculating raytraced reflections, instanced objects, etc. For huge scenes with lots of vert count, occlusion, shadows, and such, I have found that the old Octree with the maximum setting of 512 works nice, but I stand corrected if there are tests to prove this otherwise.
http://www.blender.org/development/release-logs/blender-250/ray-tracing-optimization/
@Reaction
>In the Wiki it says “If shadows are baked, lights and
>object cannot move with respect to each other.”, so
>surely that means it’s no good for animations?
The critical words are “with respect to each other.”
Although the camera may be moving around, and the characters may be breakdancing, the sun and the streets and the buildings probably aren’t moving noticably with respect to each other. Therefore, the shadows of the buildings on the street don’t move from frame to frame, so you can bake ‘em and be done with it.
The breakdancers will have to have their own shadows rendered on each frame, of course, but the point is that you don’t have to re-render *every* shadow on every frame.
If your light source is a pair of headlights on a moving car, however, you’re out of luck, because the positions of the shadows will change in each frame (it would look weird if you baked, and the shadows didn’t move with the lights)
By the way, some more things to reduce your render times:
1. If you really wanted to go for raytracing (e.g. mirrored reflections, indexed refractions, etc.), you could go to your material’s mirror tab/raytraced transparency tab and set your depth to something lower. The default of 2 is sometimes painful and causes longer render times (especially with reflective surfaces facing each other). Usually, I set it to a depth of 1 unless I want the “mirrored mirror” to create more reflections. This applies to raytraced transparencies too. However, you’ll sometimes notice that when setting raytraced transparencies to a low depth, some parts appear blackish, so you might want to just increase it a bit.
2. If you don’t really need actual reflections and just wanted to have that shiny feeling on your objects, you could go for reflection maps which are basically images (preferably HDRi or 360 degree images) then mapped on the objects “Reflection” coordinate.
My two cents. ^_^
one more way to reduce render times:
1) Faster CPU / more threads
2) More RAM
Thank you Andrew. For those that may use blender straight out of the box and don’t yet have a familiarity of the interface, this shows them where it is and what it does. Good work.
One mention on the tiling issue. As ‘artem’ pointed out, this is not a ‘fix for all’ option. It will depend on your system capabilities. I have been playing with this on a ‘duo core 1.8 with 2GBMem and GT240 Gfx’ and have found out the following.
On a complicated Physics scene at FullHD with reflections and four lamps. – increasing the tiles to around 12*8 with the threads set to 12-38 can reduce each frame by about 6% or more.
But on simpler scenes other settings are required. You will have to weigh up the time/resources taken to create each thread, against the time taken to render each tile.
Actually, increasing render tiles will INCREASE render time, unless you have THAT MANY processors. For a quad-core, 4 tiles (2×2) is the fastest you can get… IF all 4 tiles render at the same duration!
If they don’t, and you have like… One tile that has most of the work, then yes, increase your render tiles and you will get a gain in performance.
An awesome feature would be ‘dynamic tiles’… If you have 4 cores, it will do 4 tiles… If one tile finishes, it will split one of the remaining tiles in 2, etc, and always keep the CPU busy.
Hmm, sounds pretty simple to implement… And I’m learning programming… Anyone have any pointers (no pun intended) I might be able to use to help me make such a feature?
What about, using a 2nd PC to do the rendering for you.. so it frees up your main?
Thanks for the tips!!!
Has anybody suggested adding a pull-down or a selector that will allow you to choose a render “level” or “quality” that will change all of these things?
The render levels/qualities could come with reasonable defaults, but should also be editable by the user – they may want reflections in their lowest level/quality render.
About the tiles number, it requires some trial and error. Too high numbers will indeed increase the render times, but the exact number of your cores isn’t the solution either.
If you have lots of raytraced reflections in one quarter of the screen and nothing in the other 3 quarters, using a quad-core machine will result in three tiles rendered immediately and one that takes ages because a single core is rendering it.
The idea is to study the scene and look for the best amount of tilles.
Another good idea is to try the different options of “acceleration structure” under the performance tab. Most of the time the “auto” option works great, but there are cases where selecting the good ol’ octree manually will give better results.
All in all, this list is pretty obvious and the things you propose to de-activate are only useful if you don’t need them. If you need soft shadows because you want a more realistic render turning off soft shadows doesn’t make sense. If you need AO, turning it off doesn’t make sense and so on.
So what we have here is a pretty obviouse advice: Turn off every render feature you don’t need and you’re good to go.
Sounds more like something for a tweet than for a “guru” blog post.
@ Jake
Thanks a lot Jake, it really helped me, now I can make more realistic cars on blender 2.53 Beta.
I O U
A good way to reduce renter times with spot lamps is to reduce the area where shadow samples are being calculated. You can define a start and endpoint for your calculations, which should always only start/end where the objects in the scene appear. Also, making the cone radius of the spot lamp smaller makes the shadows better, because you don’t waste space that needs to be calculated. Of course these tips don’t directly increase render times but they increase the quality of soft shadows, which means you don’t need to put the memory buffer too high.
Actually an overview of Netrender would be a bonus. Its a bit hit or miss my end as I’m not sure if its behaving properly. It outputs its EXR frame correctly, but not the resulting image to requested format, in my case PNG. Just spits out blank frames at the default camera scene resolution (half 1080p). Also under the client tab its not displaying the slaves or jobs in cue, but all info shows up through its web gui.
I know its still beta, but would love to see this fully working, as it would save so much time rendering some of my heavy animations.
OS – Ubuntu 10.04 64bit 4GB ram i7 core
Andrew, I just have to say….awesome job with your tutorials. I only started using Blender about a month ago. So far, I’ve tried my hand at the volumetric clouds and am currently working on the Starcraft logo. The clouds were so-so. I was still fumbling with the UI and such so that didn’t help. However, I learned a ton. While doing the Starcraft logo, I’ve become more proficient and its looking really good for a noob if I may say so myself.
I’m having a blast and your in-depth instructions make it easy. I look forward to trying the flag. Keep up the great work!
Hi,
great stuff here! But kills me the time for an extra cup of coffee
When running Linux and haveing access to sources of the linux-kernel and blender, there is another way of speeding up the whole thing: Hand-optimize your kernel settings and
user-config.py in the sources of blender to hand tune the
CFLAGS/CXXFLAGS. I found this for an AMD Phenom II X6 T1090 useful:
-march=amdfam10 -pipe -msse3 -combine -ffast-math -fopenmp -fprefetch-loop-arrays -ftree-parallelize-loops=12 -funroll-all-loops -fwhole-program -mtune=amdfam10 -O3
Be careful not to compile the kernel itsself with these flags!!!
Futhermore: When using Blender 2.5x set the threads
to two time the count of CPU cores. Increase the count
of tiles — the correct setting of these is depedant on the scene you want to render and the size of L1/2/3-cache of your CPU.
As long as the load meter of your CPU does not reach 100% while rendering there is something sub-optimal with your setting/hardware.
HTH
Again, a really wonderful entry and a massively useful one!
You’ve been featured for sharing your expertise with others in my recent blogpost about blogging. Okay, that must sound a little strange, but at least you’re linked and for me a role model in writing tutorials with stunning results!
Another way to reduce your render times is get into your pocket and buy a GPU based unbiased external renderer like Octane(http://designkingdom.ug/articles/octane-render/) . What it does is it takes the rendering power from your processor to your dedicated graphics card. (assuming you have one). Then it renders it at super speeds sometimes 50times faster than usual. But there is a big limitation; it costs about 99 Euros for a licence.
I am a noob at blender but this is what I was able to render in 30Minutes after using Andrew’s tyre modelling tutorial:
http://designkingdom.ug/members/andrew/album/picture/10/
Machine specs: Win Vista Home Edition 32bit, Intel core2 Duo 2.0GHz, RAM 2GB and a NVidia GeForce 8400M GS graphics card.
So is it worth it? You be the judge.
If you composite a lot, If you have several render layers, render time will be high, here is one more tip to save your time.
Use “save buffer” in Render panel under performance.( you have to give the path to the temp folder to do this)
Render once, it will save the buffer as a exr file in temp folder. If you close the blender file and come back later, you don’t have to render from start, go to Node editor and just press ‘R’, to read the render layers.
Artem has a point, the render times do increase if you set it higher, because each cpu has to do more bits and it takes a while for it to go to the next bit. so really only set it high if you doing huge renders. rendering a cube at 4×4 parts took 1.32 seconds.
rendering the same thing at 20×20 took 3.77 seconds.
rendering it at 2×2 took 1.18 seconds.
but rendering it at 1×1 took 1.79 seconds.
wow i may not be great at aniamting but those render times are getting so much better!!! you rock!!!
Oops, looks like people really dont know what they are doing.
“Put gas in your tank and you’ll notice your car will drive a lot better.” “Put your rear view mirror perpendicular between your eyes and the back window.” “Close the door of your car before taking off.”
Good tips, but if you want to take this hobby a little more serious you should read in on why these tips work.
Hi,
one more “tiles trick”…
The setup:
Linux 2.6.36.1
Phenom X6 T1090, 8GByte RAM
Render:
Raytracing, Antialiasing, a lot of lamps, raytracing mirroring
Hair-Particle
Image size:
5760×3600 pixel
Tiles set to 10×10. This equals to tiles sizes of 576×360 pixel.
Blender starts 6 threads (as there are 6 cores in this CPU), when one finishes, it starts the next so that there are 6 cores under load all the time.
BUT:
The last tile, which will be rendered, is ALWAYS that one, which includes the most complex part of the picture which takes the longest time to render (in my case: The head with the hair.).
And: For this most complex part of the scene only ONE core is used, since all others have finished its work and there is no other tile to render.
Blender does not subdivide this last tile again to start again 6 threads on six cores.
The result:
99% (equals 99 tiles of the 10×10 tiles) of the tiles were finished relative quickly while one tile takes up a huge amount of the complete rendering time.
Rendering this image takes about 19 minutes to finish, working on the last tile for about 6minutes (roughly).
Now the tiles count was craked up to 900 tiles (30×30). so that the area of the previous “last tile” became 3×3 tiles.
Now rendering took only about 13 minutes.
Conclusion:
If the scene consists of simple parts, which render very quickly and only a few areas,with complex, slowly rendering contents AND those areas count is less than the number of cores/threads which could be started in parallel (PHYSICALLY in parallel!) increase the tiles count in a way, that that area becomes at least divided by a number of tiles equal (or better greater) as the number of cores/threads you system is handling physically in parallel.
It is not useful to have 9 threads “in parallel” from which 3 are waiting for I/O and/or CPU time.
Hopefully I have confused you all….
Best regards.
mcc
Feature request to the blender developper:
Please make sure, that — regardless at which part of the scene the rendering process is currently — the complete core/thread count, which is configured — is under load until the rendering is finished.
This implies the subdividing of tiles if not explicetly disabled by the user.
Hi,
While rendering a sketch anim for a project, I found that switching off Environment Lignhting (and placing Hemi light to do the same) decreased rendering time dramatically, from 3 mins/frame to ~30 sec/frame.
There was only one other light (a spot with mapped shadows).
It was dark when I woke. This is a ray of suinhsne.
holy shit!
my render time decreased from over 2 minutes to 18 secondes!!!
thanks a million times
Thank you, you guys are awesome….
New computer??, have you installed blender and it runs slowly, the solution is here:
Windows drivers, search your drivers in the main page of your ati or nvidia web site and update it, windows drivers are out date and doesnt show to your pc how to use it at max power.
it takes too long to render a high quality. is it ok that my animation takes 3 hours on rendering pls help me how to do it im new user of blender.
thanks…..