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Sebasvideo
02-16-2014, 09:49 PM
I was wondering if anybody tried exactly the same scene rendered with Octane vs CPU only but on more than one computer. If I remember correctly, scenes meant to be rendered in Octane need special shader items that are not the ones in Lightwave, correct? Maybe I got that wrong, but still, I'm digging in the forums here and reading lots of posts on Octane but I don't get much in concrete. Yes, it's fast, that much I gather, but how much faster for the same exact scene, even if it needs specific shaders?

I'm contemplating two options, with absolutely no rush since I couldn't afford either right now anyway: 1) to spend $465.18 in the Octane combo for Lightwave, and then spend a still undetermined amount in the plugin for Modo when it comes out, which would put the cost of Octane for me around $600. I have a GTX770 with 4 GB of RAM and 1536 CUDA cores, so I think I would get fairly decent rendering times with it. Or:

2) To use those $600, add a little more money, and build a basic machine, good 6 core Intel CPU, 32 GB of RAM, a decent motherboard and a cheap hard drive, since it would only be used as a render node. I already have another computer with an AMD 1090T, a laptop with a Dual Core i5, and two 2.66 Ghz Quad Cores from 2008, one of which I still have to assemble, but today I was rendering a frame that took about 25 minutes just by pressing F9 in my main computer, a 3930k with 32 GB of RAM, and when I rendered the same frame split among the 3930k, the 1090T, the i5 laptop and one of the Quad Cores (using Amleto with a 4x4 split) it went down to 11 minutes. That's more than twice the speed, with one good CPU, one decent one, and two crappy ones. If I had a 4930k to add to the mix that render time would go way down.

I've read lots of posts on Octane, and obviously it's fast, but I still have to read a post where one or more people rendered the same exact scene and frame in both and wrote down the times, along with the hardware specs.

Since I started reading about Octane my impression was that it was several times faster than the CPU, but I was trying out renders in Blender yesterday and it made me doubt. Before you say anything, yes, I admit that Blender has nothing to do with Lightwave or Octane. However, it gave me a starting point because it comes with a renderer where you can simply choose between CPU and GPU and see the difference. While using the equivalent of VPR in Blender it's easy to tell that the GPU is faster. However, when I rendered a frame that while it wasn't specially loaded it had a fluid simulation with water overflowing a tank, so there were two items that had transparency, reflection, glossiness, refraction at different values, and taking up a fair amount of the frame. I can't find the paper where I wrote down the render times, but I do remember that the GPU was faster but not even twice as fast as the CPU. Now, I barely know Blender so I can't for now do any network rendering with it, but still I don't plan on doing much with it besides fluid simulations. But that kind of gave me the idea that maybe another render node, along with what I already have, would give me better rendering times than only relying on Octane.

Besides, I don't know about Octane, but if it's anything like the Blender GPU renderer, when it's rendering you can't use the computer, it just doesn't respond. To a certain extent that also happens with the CPU, but it's worse with the GPU. You can't do anything, everything moves in slow motion or with a long delay.

Any thoughts?

m.d.
02-16-2014, 10:45 PM
The speed increase of course depends on the relative speed of the CPU vs the gpu used....

In my case my renders would be up to 10 times faster with a 590 and 2 470's vs a 6 core i7.....


But you cannot do a direct comparison, as they do use different shaders....different rendering algorithms...AA ect ect..

The only way to judge is to render to a certain quality by eye and compare the speeds....

Remember octane can not currently do hair or volumetrics...and is not a complete rendering solution, unless you are just doing architectural, or non fx rendering.

The real performance boost in octane comes from the ability to add more cards, and or update your cards...

A CPU can at best be updated in a motherboard for maybe 3 generations with an AMD setup and 2 or often only 1 with an intel setup. An upgrade in CPU will usually result in a new motherboard and fresh OS at the least...and every 2 years RAM will likely be outdated.
With GPU's you can just throw the newest ones you can buy, even into a 5 year old system. So far all versions of PCIx are backwards compatible going all the way back to 2003...

Sebasvideo
02-16-2014, 11:03 PM
Remember octane can not currently do hair or volumetrics...and is not a complete rendering solution, unless you are just doing architectural, or non fx rendering.

Actually I didn't know that, and it makes it easier for me because if I can't do volumetrics then the new CPU is a better choice.

erikals
02-17-2014, 12:59 AM
what you could do is to render most of the scenes with Octane, then render the FFX / volumetrics using the LightWave render.

Octane renders also look better, depending.

also see GPU price chart >
http://forums.newtek.com/showthread.php?131666-Octane-render-for-Lightwave&p=1365254&viewfull=1#post1365254

buy a used GTX 590

Danner
02-17-2014, 01:42 AM
Octane is fast and gorgeous, but not always faster. In my case, it's slower. Most of my renders are slow moving cameras on interiors, and after I set up the scene for speed (using cache'd shadowmapped lights and a locked radiosity cache) Lightwave renders in around 2 minutes per frame in HD. And these are not simple scenes, average is about 40 lights around a million polygons with lots of reflections and some refraction. I cannot get Octane to be noise free in less than 5 minutes on any of the scenes I've tried. Admittedly my machine favors CPU over GPU but I also have access to a 10 machine renderfarm that I don't need to pay an octane licence for each. It does use different shading system, not necessarly a bad thing, but you have to get used to that too.

erikals
02-17-2014, 01:48 AM
to get rid of Octane noise you can use Neat Video.

seems to work great... http://erikalstad.com/backup/misc.php_files/smile.gif

Danner
02-17-2014, 01:55 AM
About the unresponsiveness while rendering, it is recommended that while you are setting up scenes in Octane you use two video cards, leave the slowest out of the rendering so it's for display only.

Danner
02-17-2014, 02:00 AM
I have used Neat video, I had it at the last place I worked, it saved my bacon a few times when using Fprime. Still it didn't always work, things with fine detail could get confused for noise. (wood grain, clouds, rug textures things like that)

erikals
02-17-2014, 02:10 AM
yeah, i need to experiment a bit with using masks etc... and some other tricks

Sebasvideo
02-17-2014, 09:18 AM
Seems to me that for now adding another computer makes more sense. I can't add another graphics card because the GTX770 takes up two spaces like most cards these days, and I have two other cards, so I don't have space for it. Meaning that while using Octane I couldn't use my computer. Getting another computer means that I can leave the rest rendering while I use my main computer and then add it when I'm done.

Besides, I don't like being constrained to what types of scenes I can do with it. I mean, I wouldn't mind if it didn't mean spending over $600, but for that price it doesn't make sense to me. Besides, if it takes longer to render to get rid of extra noise, I'm not sure how much faster it would be. I do have NeatVideo but only for Premiere. I'm not going to spend money in the license for After Effects, besides, rendering something noisy and then trying to patch it afterwards is not something I would like. While it's great to clean up video sometimes, it also makes the picture a bit muddy.

m.d.
02-17-2014, 11:54 AM
Octane doesn't have to be noisy....it can be on some scenes, but that doesn't mean it is on all renders.

Danner is talking about using a moving camera with a locked radiosity cache....something that LW render can do very fast...
With a locked cache, you only are calculating the radiosity once(per field of view maybe? Not quite sure)

Try running animated objects and lights with radiosity, where you can't cache it,and you will see noise and splotches like crazy with lightwave, and where octane noise looks like film grain....radiosity splotches look hideous and cannot be removed.

In this type of scene octane will excel above LW render in performance....
They are 2 completely different render engines.....
LW has the advantage of things like a radiosity cache, which can be very helpful on interiors....and interpolated radiosity.
Kray has the speed advantage of photon mapping....

Octane has its own advantages....not always better or faster....but since I have been using the beta plugin, I have only used native lightwave 3 times in the last 6 months...and I also have kray and frpime, so in my particular renders it has been game changing.

For outdoor scenes with high instances polygon counts....octane will garaunteed beat all other LW renders in speed....
No contest....
For interiors, LW or Kray may be the better choice right now....that may change if octane ever gets surface baking.

While octane may give you a grainy noise....it is impossible to get radiosity splotches from it, which can be very hard to tune out of LW native

They all have pluses and minuses.....you can't directly compare them. It's all based on what you need at the time.
The only one that can currently render all of LW features is of course LW native....the others are to some degree speciality
renders