Nurbs Circle Extruded along path render issues

[Anonymous]

I have extruded a nurbs circle along a path in a scene to create an extending cable. I began exporting the scene yesterday. When I came back to view the render progress 17 hours later, it had only rendered 27 out of the just  over 200 frames, and the extruded nurbs circle was not even visible in the shot. Just to test, I canceled the render and rendered only the current frame, and the extruded geometry of the cable was there, but it was badly deformed and not aligned with the connector on the end of the cable. None of these artifacts are evident in the viewport

So I essentially have 2 questions here:

1) Why is the render taking so long?

2) Why does the extruded surface show up and extrude fine in the viewport, show up distorted in a single frame render, but not at all in final a sequence render?

I am at a loss.

I have attached a sample of the single frame render and the first 27 frames of the sequence render that does not show the extruded nurbs circle geometry.  I have also attached the ASCII file as well if anyone would be willing to look at it.

RENDER SETTINGS

Viewport

Distorted/Misaligned Single Frame Render:

Absolutely nothing in final render (Originally EXR beauty sequence converted to .mp4) - Attatched

[sean.heasley]

Hi @Anonymous

Thanks for attaching your files!

It's possible this is a GPU issue. What GPU are you using and is the driver version the same as our certified hardware list?

You can find our certified hardware list here!

I did a quick test render and was able to see the cable:

Also, if you scrub the timeline does the cable appear in the viewport and just not when you render or is it not appearing in the viewport either?

[Anonymous]

Hey thanks for taking a look at it!

The cable appears and extrudes properly throughout the timeline in the viewport.

Also, doesn't Arnold only use the CPU to render and not the GPU?

[Anonymous]

Also I forgot to mention that the cable also extrudes properly in the Arnold live renderview, but is distorted when I preform a single frame render, and is completely missing when I  preform a sequence render.

PC Specs:

Intel Xeon E3-1240 v5 @ 3.50 GHz

AMD FirePro W2100 Graphics Adapter

32GB RAM

OS: Windows 10 Pro

[sean.heasley]

Hi @Anonymous

Yes Arnold is CPU based but GPU issues can cause issues like this sometimes.

I tried a sequence render as well for about 10 frames and I am able to see the cable fine so it looks like its something on your end.

A quick test you could do is to export everything as an fbx and import that into a fresh new Maya scene and see if the same issue occurs.

[Anonymous]

Okay, I will give that a shot. Much thanks!

Also, do you have any suggestions as to how I could speed up the render? This has to be rendered out at 1080P. How long did it take to render out the 10 frames on your end? What resolution was it set to?

[sean.heasley]

Hi @Anonymous

I had it set to the standard HD resolution which is pretty low quality and it took a solid 30 mins to render the frames.

The render time taking a while is most likely due to the amount of polygons, materials, lighting and animation that are occurring.

It's also hardware dependent, I personally have an Intel Xeon e5-2650 12 core which helps a good bit with the render time.

While your render will take a while regardless, this video does a pretty solid job breaking down how to optimize a render.

[sean.heasley]

Hi @Anonymous

I'm just checking in again to see if you need more help with this. Did the suggestion I provided yesterday work for you?

If so, please click Accept as Solution on the posts that helped you so others in the community can find them easily.

[mspeer]

Hi!

I don't think it's a problem of render settings or the GPU.

The problem may be caused be the changing topology of your cable.

I highly recommend to update your Maya to the latest version (and also Arnold) to see if that solves your problem.

To reduce render time lower polygon count in the scene and quality (samples) in Render Settings.

(Also optimize materials and lights)

[Anonymous]

Hey, I just adjusted the scale of the NURBS circle that was extruding along the curve slightly and it seems to have worked. HOWEVER, this scene is still taking an excruciatingly long time to render (approx: 20 hours to render 15-20 frames.) I've gone through the tutorial mentioned earlier in this thread, adjusted the  samples and Ray Depth of each parameter while viewing the corresponding AOV. Nothing seems to help. People have mentioned to me that programs like Lightwave render scenes much more quickly (abeit the end product always looking like something straight out of  a late 90's/early 00's direct to VHS sci-fi film). However, every scene I've rendered with Maya so far takes anywhere from days to weeks to render. Is this just the nature of Arnold compared to other rendering engines? Is it just more advanced than Lightwave's renderer, thus takes longer? It seems to handle indirect illumination much better by comparison, but the render times are 100X longer. Would converting my smooth mesh previews to polygons help at all? There must be a more efficient way to render or even construct the scene. Please feel free to download the attached project file and critique my process. It would be greatly appreciated.

[sean.heasley]

Hi @Anonymous

Render times come down to quality/size of a scene and hardware.

My machine here at Autodesk has a powerful Intel(r)Xeon(r) cpu e5-2650 v4 @ 2.20ghz and it still took about 30 minutes to render like 7-10ish frames of your scene. If I were to render your entire scene on my machine it would probably take a solid 10 hours or more.

Like @mspeer mentioned, you would need to lower some poly counts and optimize your materials. Aside from this, purchasing more powerful hardware will also result in faster render times.

If you think there is a serious issue with your machine render times you could try setting up much simpler/cleaner scenes and try rendering those to see how long they take to make sure there isn't a drastic difference.

[mspeer]

Hi!

The render settings are far away from optimum.

I was able to make rendering about 5 times faster with some minor changes for render settings and lights.

With further optimization you might be able to decrease render time by a factor of 10 or more.

[sean.heasley]

Hi @Anonymous

I'm just checking in to see if you need more help with this. Did the suggestion that @mspeer provided work for you?

If so, please click Accept as Solution on the posts that helped you so others in the community can find them easily.