Cycles, maximum 30min Interiors, 1080p, GTX 465

– Beginning of Rant —
So I was afraid of using cycles because I thought it was a slow render engine. I have seen threads where people “cook” renders for 10 hours or more. Also I got an Octane license a while back when it was in early beta, but got rather disappointment when I understood that it was not in fact a “fast” render engine as advertised.

I have been using Blender Internal because what I am looking for are fast interior renders for architectural projects, 1080p images in maximum 30 mins is my limit. I simply do not have more time for rendering, and using a renderfarm service is not an option.

However I got curious if I could indeed use Cycles to produce 30min interior renders at 1920 x 1080. Mainly because I noticed that Blender Internal got very slow when you add reflections to complex interiors.

I discovered that Cycles does not have to be slow, the rendertime is proportional to the amount of samples you use. And with my old Nvidia ENGTX465 some 1000 samples renders in about 20-35 min. I can add glossy materials and textures as I like, the rendertime does not change unlike with Blender Internal. The only problem is noise. And I think I have found ways to reduce the noise to an acceptable degree.

I use emission planes in the windows, with a high emission value but dark color. And clamping at 8 also smooth out the noise. And also you can apply some selective gaussian blur in Gimp but I do not think it is necessary.

My option is to use Blender Internal that is basically noise free, but the trade off is reflections and some lack in realism because the faked indirect lighting, also interior lights does not produce the nice effects. I think these renders are good enough for printing as fold in views on presentation sheets, that is some 20-30cm wide on paper.

– End of Rant –

So now the question is, do you think these renders have an acceptable amount of noise?

31min render. No post processing. DOF rendered with Cycles.


24 min render. Selective gaussian blur added in Gimp.


20 min Blender Internal comparison.


While looking at your pictures, i played a bit and stumbled upon something out of pure trial and error…
you might give it a try it does away with non caustic noise, and perhaps improves it also on places where you still got it.
its done in compositing mode; make sure to use backdrop and all the nodes as displayed (and then press render button).


pls write back if you find this usefull for your scenes

That is indeed interesting, however, blur filters in any form wash out details in textures, but these might be overlayed with a grayscale simple render… have to take a look at this in more depth!

What about this one? I had to lower to 500 samples for a 27 min rendertime, since I used experimental mode for rendering the carpet. I added some Ambient Occlusion, 0.1, 3m for some extra fake light that I think removed some of the noise.

Cycles 27 min render.


Clamp lowered to 3,0 and Ambient Occlusion set to 0,2 with 3m distnace. It did wash out the interior lighting to much, but the render is very clean att 500 samples.

27 min render.


Ah, but you can render the direct lighting in Blender Internal as a clay render and overlay it! :smiley:



and using a renderfarm service is not an option

may ask why? I render FullHD frame, in 3000 samples and it cost me 2$ with is acctualy free

250 Samples. Clamp 2,0. No AO (Discovered that AO increase renderspeed with 30% adn wash out colors).

10min Render. Added Blender Internal clay direct light render in Gimp as a Dodge layer.


Well at the moment I am working on my Diploma project, so I do not have a budget for renderfarms. And I am planning on starting an architecture business later this year, but then I would be selling designs and drawings. Renders are a good way of presenting your design but not actually the primary commodity that you are producing. So for me it is secondary. Renderfarms would be an option if I do not have time to render myself, or it would make sense economically.

2$ for one render, but after 100 renders you could buy an used GTX 580, and so on.

Short answer, 2$ for each render will be alot of money after a while.

19 min. 500 Samples. Clamp 2,0. No AO.
1 second render in Blender Internal with direct lighting.
Drag and pull to gimp and change the blend mode to Dodge and export. 5 seconds.

I think this is clean enough, for straight forward architural design presentations.
[ATTACH=CONFIG]279094[/ATTACH]

And with a Overlay of a 2min Blender Internal render.



14 min Cycles + 2 min Blender Internal. And some adjustment of the levels of the BI overlay in Gimp to get the right highlights.


BTW i checked one doesnt loose that much detail in textures it all depends on how you set it up; i got fair results using cycles and only 15 difuse 15 glossy 9 AA samples (non quadratic!!); the trick is to add more layers; combine the layers to get differences in object (or even plain collor as from textures) and then use that blurring method. the effect is less with high sampled renders (100+ or so) but then you probaply dont need it. I think its a way to reduce; a good movie to start with to get yourself familiar
with it is

Dough one can do it in multiple ways; for example combine all low noise layers (check’m with the viewer node), and combine those layers and next do that bilaterl blur … or … for each layer have different bilateral blur settings and finally combine them.
In fact i like this (to me) new method more then the defocus node.

OH ps for your last image, notice the chair wood textures, at some parts og to edit mode select areas then go to UV editing mode, and turn 90 degrees. BTW those renders are quite nice; i wonder what hardware you have that it requires you to do 15 minute renders for it.

There are also some renderfarms that allow for a single (final) render p day for free…

An old Nvidia GTX465, so I have pretty shitty hardware. Basically it is the Clamp that cleans the speckles up.

Tjena Martin,

Didn’t you use V-ray before, and wouldn’t it be faster and cleaner for this kind of render?

Cheers

Tjena Jakerlund :wink:

Yes it would be faster, but it is not open source :wink:

Although, adding to much glossy reflections Vray gets slower and slower. I think 1hour render for an complex interior scene is pretty common. With Cycles you can add as much reflections you want, it does not get that much slower, only noisier.

But with time, I think GPU rendering will be faster than CPU, I do suspect that a Titan with Cycles would be faster than a i7 with Vray, using the right technique.

Very interesting thread and the overlay from BI is an interesting technique! Thanks for sharing that.

I think you can’t compare it this way. Cycles will need more samples to eliminate the noise and then it will also take longer.

Hm, I don’t know much about vRay. Can there be cases, when a CPU render is faster then a GPU render?

Yes, but the increase in rendertime is not as drastic as with Blender Internal or Vray.

Renderengines using CPU is generally faster than the Unbiased ones that works well with GPU. So actually the CPU in itself is not faster, but the software is.

So, is this to noisy or is it acceptable?

22 min Cycles + 2 min Blender Internal Direct Light + 3 Seconds Blender Internal Sunlight. I did also a test with AO, rendered at 29 min, but the 22min render was better. Also the BI pass helps to define shapes.