OCDS vs IRAY render speed (and feature) comparison Tweet

[DrHemulen]

I've been playing a bit with Iray, and it's been really hard to figure out how it compares to OCDS, as looking at renders is a very subjective thing. I sat down and thought about it, and came up with the following method:

1: Render OCDS image to 500 samples and note time use
2: Render Iray image for the same time
3: Compare images

The render time is chosen so there's still a lot of noise. Then there are actual noise levels to compare. This is more informative, than comparing two "finished" images and looking at how long they took to render.
Here's the setup. I know it's comparing apples to oranges, but at least I'm trying to use apple sized oranges and orange coloured apples
Rendered on a 2 gig GTX 970

Scene:
DAZ V7
Vigilante Boots
Krayon Hair
Dance studio
Barcelona Rooftops HDRI
Single plane meshlight.

Prep:
Octane:
Model settings as default
All V7 textures resized to 1/4
All textures autogenerated. V7 model assigned custom themplate with D.Ordiales skin. Basic diffuse/specular mix material I found really good and "cheap" on render time and VRAM.
No displacement
PCM kernel
Octane reports ~1 mio triangles in final scene.
Render time 707 seconds in "final" mode.

IRAY:
Default textures (All V7 textures resized to 1/4)
Subdiv at rendering set at 1 for all models to match OCDS (defualted at 3 for V7, scene was over 20 mio triangles).
Default settings for Iray photorealistic.
No displacement
Octane reports ~1 mio triangles in final scene
Render time 707 seconds.

Results
OCDS


Iray


Conclusion
The Iray renderer seems a lot faster, at least on my setup. The image is very close to the default convergance criteria. The OCDS image still has a lot of noise in it at this point.
VRAM management is a LOT easier in OCDS. In Iray you basically can only see if it fails to fit everything i VRAM when you run. You have no idea how much space everything takes up. As the default subdiv level at rendertime is at 3 for G3 figures, this takes up quite a bit of ram when using Iray, and it can be hard to figure out how relevant each model is for VRAM optimization. You manually have to resize textures.

I know the OCDS image is colder, didn't notice the meshlight was at different temps when I ran them. I tried to change it in OCDS but then the window frame started glowing, and the window turned solid without any noticable changes to the materials, so I just called it a day.

[face_off]

It looks like there is some shadow noise in the Octane render. Reducing the Kernel->Path Termination Power may clean this up significantly faster.

Paul

[face_off]

Also - if the render is running for 7 mins, increase the Kernel->Coherent Ratio (try 0.5?). And PT might be a better kernel for that scene.

Paul

[Spectralis]

My experience with certain scenes is that sometimes IRAY is faster and at other times OcDS wins. What I find difficult about IRAY is the slow viewport update compared to OcDS. But then if you use presets for lighting and materials then IRAY has the edge. Also OcDS lighting seems more versatile, especially with HDRI. For those of us with OcDS I don't see much point in IRAY, especially once we have a final release but if I didn't have OcDS there seems little point in buying OcDS now that IRAY is here.

[DrHemulen]

Once we get a fully functioning plugin I'd agree with you (assuming we don't have to pay a couple of hundred to upgrade to O3 to get it), but right now the time spent on frustrations of disappearing materials on load, weird stuff (like the windowframe material starting to glow) and crashes just means that it doesn't matter which is faster on rendering time.
I really want to go with OCDS, I think the render also has a more real, less flashy quality than the Iray renders.

Face_off: To me that image is noisy all over, not just in the shadows PT gives me a lot of fireflies on the skin materials I use, so I almost always use PMC. I'll try fiddeling with the parameters you mention and try again. All these little things is why comparison is so hard. Render time is 707 seconds ~ 12 mins.

[DrHemulen]

Redid the image with the suggested changes in PT:



Looks a lot better, 1000 iterations in the same timefreame. Glow is just reflected light it turns out.
Hair opacity went crazy unfortunatly.

[face_off]

Hair opacity went crazy unfortunatly.

You need to lower the ray epsilon to fix that.

Paul

[linvanchene]

I realize that this thread was ment to compare render speeds but since other users are adding their statement it seems important to me to provide a counter argument to present Otoy with other opinions.

For those of us with OcDS I don't see much point in IRAY, especially once we have a final release but if I didn't have OcDS there seems little point in buying OcDS now that IRAY is here.

IRAY is currently a great option for all those people who want to purchase licensed content, place it in the scene and hitting render without editing any materials.

Nevertheless for all those who are interested in advanced material editing in a production ready time to quality relationship the DS version of Iray is not an viable option.

The very moment you actually want to create your own materials you are faced with the same limitations the 3Delight implementation in DAZ Studio had:

Shader Builder and Shader Mixer are far inferior to the OctaneRender NGE.
DAZ3D may be interested in selling shader products and may not be motivated to actually provide a render solution with all the advanced features so the users can fully customize their scenes with ease.

Have a look at this:

V7 Iray Head surface shader mixer layout.

While the standalone OctaneRender NGE does a great job of organizing all the countless nodes to a manageable group the DAZ Studio Shader mixer creates nodes for every little parameter without giving any advanced options to group and combine nodes in a reasonable time frame.

- - -

Unfortunately the OcDS advantage in material editing has been completly ruined by the latest BETA version of OcDS in which the autoconversion creates mix materials instead of the simple default material layout it did in all previous versions.

The key of a great autoconversion is to provide either

- a simple default conversion that then can be fine tuned with more advanced features by the user
or
- a truely detailed autoconversion that uses a complex system of rules to deceide in which cases which node combinations are used to recreate to 3Delight or Iray material versions.

- - -

From a business perspective OcDS could have a very bright future if Otoy finally would concentrate on the core strenghts of OcaneRender and build around it:

The NGE is a great way to customize scenes.

But unfortunately only a few plugins actually have a version of the NGE that is comparable to the standalone NGE.

And then sadly while the standalone has a fully functional NGE it was not found important enough to actually add a timeline to the standalone to make full use of the NGE.
To me it seems that Otoy has not even realized the full potential the NGE could have combined with animation.

- - -

Bottom line:
The DAZ Studio forum is full of people who ask for

- basic render features OctaneRender has implemented allready and are simply missing in Iray
- advanced tools like batch and cloud rendering
- advanced animation features with a versatile timeline and keyframe system

In general OctaneRender could have the advantage of delivering a full pipeline in which users can use the same render engine in many different software packages.
As far as I am aware there are no Iray versions announced for AfterEffects, Photoshop or Zbrush.

OctaneRender could provide all those advanced features that are needed to work in a professional environment creating CG images and videos in a reasonable time to quality relationship.

[DrHemulen]

The idea of the thread is simply to make a rational, objective comparison. Speed is only a part of that

I agree completely with what you said about the node editor, I took one look at the IRay node tree and gave up immediately.

Can you do batch renedering with OCDS now? How does that work? I tried exporting to the standalone and render there via the command line, but I wasn't able to figure out how to use the camera i had in DAZ?

Hair opacity went crazy unfortunatly.

You need to lower the ray epsilon to fix that.

Paul

It wasn't there on the render before, and it disappeard when I pressed render again. Exactly the same setting, without touching rayepsilon. Wouldn't you expect consistent errrors if rayepsilon was wrong?

[gaazsi]

Hair opacity went crazy unfortunatly.

You need to lower the ray epsilon to fix that.

Paul

is it possible to hand out some kind of... tutorial or guideline with tips and hints like that for new users? i spent days and weeks testing things like that by myself and i bet i dont even know the half of the possiblities of octane until now

even without all those little bugs remaining ocds is so much better than iray in its current state. but... nvidia is a huge corp meanwhile, if they just dump enough money into their project... iray is more or less brand new