Daz 3D to Blender, some questions about workflow and memory issues

Vincentus

Hello,
I believe this question has been asked many times, but I need help with my overall Daz to Blender workflow.

I want to create and use Daz characters in environmental or architectural renders made in Blender.
I want to pose them too of course, but I don’t plan to animate them, I’m considering it for the future though. (by using Blender animation tools instead of Daz one’s if possible).
And my goal is to achieve close to realistic renders.

I don’t know Daz 3D very well, barely used it, but I’m wondering if this is possible to :
- create characters in Daz
- use Marvelous Design for fitting clothes “correctly” (I saw this video about this : https://www.youtube.com/watch?v=M9o8skP9kLc)
- then create a scene with a mix of Daz but mostly Blender props/assets
- and then use Blender for overall tinkering and mostly lightning and rendering.

I tried the official Daz to Blender Bridge plugin in order to import Daz character to Blender, but I obtained better result with the Diffeomorphic plugin (v1.5.1).

But here's my main issue right now :
My PC is equipped with 16Gb RAM and an AMD VEGA GPU (8Gb VRAM). Everything seems to work fine with EEVEE renderer, but Blender (v2.90.1) or my whole computer crash with Cycles.
When the PC doesn’t crash, Blender display an “blender split kernel error invalid ray state” or “OpenCL not enough memory” error.

However, CPU rendering with Cycles didn’t crashed, but render time isn’t as quick obviously.
My RAM and VRAM is 100% used, so I believe it’s the issue, but I’m still surprised.

Do I need to upgrade my RAM and GPU, or in other words, does everything require that many memory, or something is off ?

I know I was quite focused on my memory issues, but I’m still interested about finding a good workflow overall.

And I saw this interesting thread which will help me in some area, but I allowed myself to ask here mostly because I’m confused from every threads or videos I saw about this subject, and from all the failed attempt I had as result.
(https://www.daz3d.com/forums/discussion/407006/daz3d-to-blender-workflow).

Sorry for the long message, I made a better draft before, but I loose it because of a browser crash.

If someone have some advices about something that I mentioned, I'll appreciate.
It's about time I ask for help. Thank you.

Krys Kryngle

I think a lot of it depends on what you are creating.  My workflow is almost exactly the same as yours, Daz characters with Blender background and assets, rendered in Blender.  I experienced similar rendering issues as well so I'll share my experience and hope it helps a little.

I started with an older setup like yours and thought I could solve all my problems with a faster graphics card with more memory.  I bought a Gforce RTX 2070 and it was definitely faster in some cases, but it was not the answer.  The new Optix rendering that was available was wicked fast, but it would run out of memory with larger scenes.  I can use it to do single character renders with no background, but as soon as I add a background and hdri, it runs out of memory.  Then I would switch over to CUDA, which uses both graphics card and processor, and with large scenes I would still run out of memory.  So, even with a faster graphics card I had to resort to cpu only rendering, which was slow.  My solution was to upgrade my processor to an AMD 12 core and install more RAM.  Now I can use Optix to refine individual aspects of my scene and CUDA (gpu+cpu) to render huge scenes.  I have not had any memory issues since upgrading.

If upgrading is not an option, I think using smaller textures will help with the memory issues.  Diffeomorphic has an option to resize textures which may help.  All of those 4k character textures take a huge amount of resources.  Also using basic light sources instead of hdri's might help.  Once you get everything looking the way you want, then maybe bump up the texture sizes to get the level of detail you want and let it render on the cpu overnight.  I have not tried this approach, just a suggestion if upgrading is not currenlty an option.  Another easier option might be to use Blender's 'Simplify' panel to lower subdivisions and texture sizes until final render.

Vincentus

Hello, Thank you for your answer and sorry for my late answer.
You kinda confirm my thoughts about all of this. I knew that I will most likely need to upgrade, and I planned this for quite a time in the end.
I plan to purchase the upcoming 12 cores AMD Ryzen 5900X + their 16Gb VRAM GPU + 32Gb Ram, early next year.
That will most likely be overkill for some games and half of my 3D works, and quite an expensive upgrade for just a "hobby" and "video games" - but at least I won't need to upgrade before a few years at least.

Also, I tried to play a bit more with the Diffeomorphic plugin, and I definitely achieved better AND faster results with it compared to the current official DAZ to Blender Bridge one.
But I'm still surprised that just a character alone literally eats up all my RAM and VRAM in Blender Cycles.
But I managed to get some results in CPU only mode that I find "good enough", especially with the use of Denoiser.
With my current 6700K CPU (4 Cores at 4.4GHz) I managed to render a character only in less than an hour at 1080p.

So even IF a 16Gb VRAM GPU won't be enough, a 12 Cores CPU should be more than okay.
At worse, I believe that rendering environments with GPU and characters with CPU will be possible and kinda effective.

Well, again, thanks for your answer.

camilo

I'm not completely sure but I think Nvidia GPUs works better with Blender, although it has less memory than AMD GPUs. If you have some budget, try this plugin instead of hdri https://blendermarket.com/products/pro-lighting-skies. I can't guarantee that it will solve your problems because I haven't used it yet (it's on my wishlist) but according to the developer, it uses less memory. Try also reducing mesh size for characters in the background or render them separately and join the images in post.

My current setup is an Nvidia 1070, 16G ram and i7. I'm just starting, but I'll report here later if I have any useful tip.