Getting low render times for animations in Cycles

Support Lighting and Rendering
1

I make small animations with Blender for some time. Till now I went with Blender Internal, but I feel the time has come to switch to Cycles. I opened up a simple scene I got from Blendswap a few days ago, and started configuring the lighting and messing around with the render settings, in hopes of getting an acceptable render time without noise. Obviously I run into the most common inconvenience regarding Cycles: It’s either huge render times, or an ugly and noisy result. This problem has been discussed before, but I’d like to know if there are any solutions for creating animations in Cycles without them taking months to render.

I have an Intel Core i7 920 CPU, with 4 cores and 8 threads. By default it’s 2.66 GHZ, but I clocked it up to 3.15 GHZ. GPU rendering is out of the question, since I stick with ATI and its drivers don’t support OpenCL. The animations I plan to make are 1920 x 1080 @ 60 fps, and some might be as long as 10 minutes or more… meaning 36000 frames.

I reached a somewhat acceptable result at 1 minute per frame… by disabling light bounces and using direct lighting (0 diffuse bounces, 1 glossy), not using any mesh lights and sticking with point / sun / spot lights (less noise and less time), using a Despeckle composite node to hide some of the noise, and using just 16 samples in the Render tab.

Even so, my scene is too noisy and 1 minute per frame is too much! 60 FPS means 1 second per hour, and since I can only render approximately 10 hours a day, I do about a minute per week. This means it would take over 3 months to render an animation, which is a lot.

Are there any less known features and optimizations I could look at, and any sacrifices in regard to lighting quality I can further make, to somehow get a noise free result under 30 seconds per frame? How do people who make animations in Cycles handle the issue of render time overall? Other than using a render farm, which I’m already looking into if all else fails… also don’t suggest that I get a Nvidia card, I like ATI apart from the lack of OpenCL.

2

Let’s see the noise in a frame.

Is 1920 x 1080 100% necessary? Probably not. Save a lot of render time by settling for lesser images.

You can bake the lighting and materials together.

ways to eliminate noise
-Proper lighting for one, use big emit planes
-Use indirect clamp in the render tab
-Composite/blur

I don’t see anyone doing it and call me crazy but I like the idea of a noisy animation. If you make a noisy animation. I’ll watch it if the story and animation are good.

3

I have a single nVidia GPU and while it does help, it does not solve the issue of Cycles takes too long to render. I trade 6 CPU buckets for 1 GPU bucket.

If you have to throw mesh emission out the window and use only direct lighting one has to question what is the point of using Cycles to begin with? The camera features are nice, like DOF.

I face the same problem, as an animator Cycles is just too slow.

Lighting with the world options seems to offer fairly quick and evenly lit scenes. If you use a ‘real’ HRDi image, not just a jpeg, you can get shadows from the HDRi image as well. But then you are stuck with that ‘style’ or look. (You know AO candy coated world)

I have been fussing with this all weekend and ultimately end up ‘specing’ out a new computer. Which really is not in my budget at this time.

Cycles still can not offer up a speedy solution for night time based lighting. I have a scene with multiple cars, each having headlights and there are street lamps in the scene as well. Originally I started off using emission based materials for the headlights and street lamps, but emission lights do not work naturally and the Cycles math is wrong for such lighting attempts. You can’t effectively control the distance that a light travels in Cycles, compared to Blender Internal which has a distance parameter for the light throw and nice decay. You end up with too many firefiles after you turn up the energy too much. So I replaced all the light emission materials with real spotlights. This did improve the look a bit but increased render time to a point where animation is not reasonably possible.

tile_proc_street_lamps-4.jpg1280×720 180 KB

So I decided to give up on night scenes and try a well lit daytime scene. This 25 second animation took over 15 hours to render @1280x720 using mere 180 samples per frame. It still is not good enough for final quality and has a grainy overlay that can be seen throughout the animation. I tried to cover up some of the grain with vector blur which does not work in all cases.

I still play around with Cycles but I face the same challenges as you mention with extremely long render times and grainy output.

Have we reached the point where an animation simply can not be rendered with Blender using a single machine?

Are we expected as end-users to bite the bullet and render our animations on a farm?

4

Hi, for render times < 1 minute a pure pathtracer like Cycles is not the way to go.
There are many things you can optimize but for complex scenes in HD less than 1 minute is not realistic.
For the short movie Caminades 40 minutes per frame was needed on single i7 CPU.
Use a scanline render engine like BI or maybe Yafaray for fastest render times but not photorealistic results.
If you need to use Cycles this is may an alternative:
Take a look to http://raypump.com/ , it is free for 1280x1080 single render at 300 samples for testing.
Raypump render on multiple Tesla 12 GB GPU.

Cheers, mib

5

Thank you for the answers. A resolution lower than 1080p isn’t okay for the final render, although I will use 75% or less quality for all test renders until the very end. As for using Cycles without bounce lighting, I hate having to do that too… but I still think Cycles has better quality than BI even so, plus all models I’ll be making or downloading have Cycles materials set up, while I also need to learn Cycles better and get more used to it.

Baking the lighting is indeed an interesting possibility, but I’m not sure about a few things in its regard. Can all lights be baked per-frame, so this also covers animated objects? Or would some dynamic lights still have to shine on top of lightmap lit surfaces, which isn’t a combination that feels very stable.

Here’s an image from my test render. I took a screenshot so the render time and settings are also visible.

http://oi60.tinypic.com/2ic1cf5.jpg
2ic1cf5.jpg1600×900

6

What I wouldn’t give for a render time per frame like that. I’m working a little completely enclosed project in YafaRay (With Many Area Lights) and it looks like render times will run from 4:30 to 6:30 per frame at 720p.

1080p is out of the question for anything but the simplest animation on my machine regardless of what renderer I use. And, I might bite the bullet and go from 24 fps to 30 since H.264 seems to have a stuttering problem occasionally at 24. Your choice of 60fps interest me since I have no idea why. Also with a moving camera most of us accept a little noise. And, when your camera stops for a shot you can of course clean that up since it’s a copy - paste thing then.

7

Ouch… I’m sorry to hear others have this problem to an even greater extent :frowning: 5 minutes per frame at 720p & 30 FPS sounds like you can only do really short animations. Although I imagine you didn’t do all the compromises I have in my render… such as turning off bounces and mesh lights and only using 8 samples, which I’m aware is pretty ludicrous.

As for why I use 1080p and 60 FPS, it’s because I want my animations to be at today’s quality standards and properly use the monitors they’re being viewed on. Most monitors are full-HD and run at a refresh rate of 60 Hz, so this feels like the sane quality standard of today. 30 FPS is okay too, but I find that in both games and videos the difference between 30 and 60 is quite palpable.

Anyway, I managed to improve things in my test scene even further, and somehow succeeded at getting down to 30 seconds per frame! One additional trick was to set the Min samples to 0, and only leave Max to 4. Another was setting AA samples to 4, and give the little lamp an extra 4 samples (branched path tracing FTW). Using a blur composite node also hides some of the noise, although also a bit of the fine detail.

http://i62.tinypic.com/j63jvm.png
j63jvm.png1600×900

8

One of the problems with Cycles’ noise is that it is static - it doesn’t change from frame to frame and therefore is very prominent in the render. To counter that, you can enter #frame under Sampling > Seed. This will change the noise pattern from frame to frame, making it much less visible (gets more of a film grain feel).

Your 60 fps is much above current standards IMHO. The fact that monitors run at 60Hz has not much to say about the frame rate of the source material. Remember the outcry when Peter Jackson filmed the “Hobbit” at 48 fps instead of the usual 24 fps?

9

Aha… I didn’t know about the #frame trick, thank you! I noticed the seed option, but was initially thinking about keying it and adding a noise modifier to the curve.

As for the FPS, my idea was that if monitors run at 60 Hz, they can display a film at 60 FPS for maximum quality. I can’t say I checked many video files using such a high refresh rate, but I know that in games the difference between 30 and 60 is highly visible.

10

Sorry for being sarcastic, but have you maybe heard about such media like television or cinema?
In cinema films are played @24fps. In TV (at least in Europe) @25fps. America and Japan use 29.97fps.
No one uses 60fps.
Use motion blur and you’ll get nice filmic effect. There’s no motion blur in games, that’s why it looks so bad at low framerates.

11

Hope you don’t mind me jumping into the discussion…

Wouldn’t adding motion blur increase render time?

12

Do not confuse Hz (Frequency) with FPS (Frame rate).
That (60Hz) value is an utility frequency. It used to be very significant for image projection & image transmitting in era of analog Broadcasting TV Systems. Americas have 60Hz vs. EurAsia 50Hz… Google more…
Adding anything xtra (motion blur, AO…) will add to render time.
Good to know what to render raw (+passes) and what to do in post (motion blur, glow, flairs, CC…)

13

Here is a Blender Guru tutorial on Cycles baking.

It seems baking does not allow for animated objects or lights so it really is a tool for the “still” artists or architectural fly-throughs that have no moving lights or objects. Every object in the scene must be UV unwrapped as well. I am not sure how well that fits in with Cycles procedural based materials.

14

@MirceaKitsune, Guy you mention making small animations with Blender Internal. Then suddenly you decide to move on to Cycles and put out a major production of Ten (10) minutes at 1080p rendering on the CPU no less. Yes, a Ten minute animation is a major production for anyone by themselves.

And, there is a German guy with a WIP on this forum and a killer machine who finds 1080p just not realistic using Cycles. And, KILLER MACHINE should have been in quotation marks and Bold font. Not only that but many of these guys will tell you four (4) minutes per frame using Blender Internal and 720p for a output is not uncommon in animation.

So this thread requires watching since maybe you’ve found the Holy Grail of render times. The sure fire silver bullet that has simply eluded the rest of us. Let me ask you one question right up front. Will your camera be moving in this animation?

Please excuse our sarcasm here. When I first read what you were purposing I thought maybe you had a Pixar workstation with V-Ray on the HD. Yeah, without a doubt this thread requires watching. Please keep us posted with maybe bigger screen captures.

15

I face the same problem, as an animator Cycles is just too slow.

Lighting with the world options seems to offer fairly quick and evenly lit scenes. If you use a ‘real’ HRDi image, not just a jpeg, you can get shadows from the HDRi image as well. But then you are stuck with that ‘style’ or look. (You know AO candy coated world)

RIGHT ON ATOM, MAN. The blasé, blasé, Cycles look so often seen with no lighting but a HDR.

16

Render times… Well…
Let me give you the real life example:
In my company some time ago we created fully 3d generated TV commercial 15sec, 25fps, 1920x1080.
It was rendered in Maxwell.
Nothing really special, but we had quite a lot of plants and so on and wanted to get photo realism.
Render times on one machine varied from 1.5hrs to 7hrs per frame.
We had 15secs which at 25fps gave 375 frames.
We used a little farm of 15 computers of very similar specs.
Because we had much more of those difficult frames than those easier ones - we ended up at average render time of 5 hours per frame, so it gave 375 x 5 = 1875 hours. This divided by 15 machines gave 125 hours.
It’s obvious that we had to plan for some errors, some additional passes, pre-renders etc.
That’s why we planned 2 week JUST FOR RENDERING.

Remember that I am talking about 15 seconds…

I give here rather extreme example. Normally when we use CYCLES for simpler things I end up at about 10 to 20 minutes per frame on one machine and use 5 to 10 computers. I still don’t talk about complex scenes… Just pack shots or something similar.

So when I hear somebody complaining about having render time per frame of 1 minute or so… Well… Welcome to real life :slight_smile:

17

Do you know how much it would of costed for a renderfarm to do that job?

18

@theoldghost: So far I made small test animations mostly, but I want to make stuff as long as 5 minutes or more.

That said, this is the first time I really discuss the issue of render times with other Blender users, or the resolution / FPS standards. I am surprised that at this day, 1080p over 720p or 60 FPS over 30 FPS are considered useless, and can’t really agree there either… although I’m less surprised they’re considered a luxury with Cycles.

I don’t have a super computer however… who wouldn’t wish :slight_smile: Like I said I have an Intel i7 920, 4 cores + 8 threads @ 2.66 Ghz (overclocked to 3.15 Ghz). And unlike Nvidia users, I don’t have GPU rendering, which would have probably been very helpful. Blender & Cycles are one of the things that make me most impatient for cheap 8-core + 16-thread processors from Intel though, which I’m hoping will exist by 2016 at most.

And yes, the camera will move all the time. I understand that makes noise even more obvious unfortunately…

19

Render times… Well…

Thanks @BartekSkorupa for the real world examples. Now that was informative.

20

@MirceaKitsune, now hopefully you see why we were wondering where in the hell is this guy coming from.

I give here a rather extreme example. Normally when we use CYCLES for simpler things I end up at about 10 to 20 minutes per frame on one machine and use 5 to 10 computers. I still don’t talk about complex scenes… Just pack shots or something similar.

And, the man pretty well covers his experience with Cycles at work for a SIMPLE animation. My little project was taking every bit that long in Cycles while I was accepting noise he would find unacceptable in his work place. Not to mention the hassle of UV unwrapping to even get there.

And, that is why a Blender Internal (Scanline Renderer) and ‘YafaRay’, using Direct Light, are still valued tools for those of us at home attempting to animate. And, when I say animate I’m talking about a moving camera and not some work around slide show.

You have a decent CPU but no more so then he has at work I suspect. As a matter of fact you might have a CPU which would run through renders in YafaRay with Direct lighting and Caustics like shit through a goose. You do know YafaRay is free don’t you? And, by like shit through a goose I mean maybe 4 1/2 minutes per frame.

You’ll probably look back on this thread and start laughing and we’ve all done it believe me. It was almost like this guy thinks he can do that ‘Pixar Thing’ at home. Well, Pixar has frames that take well OVER A DAY on render farms. And, god only knows what that cost them.

And, by the way my animation won’t be that short. But, if I’m extremely lucky and willing to accept a little noise with a moving camera it might average five minutes a frame. Probably more like five and a half minutes. But, animation isn’t for pussies. The man mentioned two weeks to render with a network of 15 computers and I assume they were working at night. My effort will take way longer then that.

So welcome to the wonderful world of animation on a home computer. A world where compromise is a steady companion. ‘The sheen on that floor looks real nice’ ‘But, cost a minute in render time per frame’ Or, as the man said; ‘…Well… Welcome to real life’

But, I do thank you for the thread, guy. At, my age I need a laugh and believe me your thread here was like a breath of fresh air in that respect. And, once again we’ve all done it. LOL Hell, I’ve done it in spades. Take care and it’s nice to have another animator on here.

You know there was life before Global Illumination and some really nice work being produced. And, this forum is full of work still being produced like that. Once again thanks for this thread. It’s been a hoot.