Chaos Corona Forum

Chaos Corona for Cinema 4D => [C4D] I need help! => Topic started by: 3dkobi on 2019-06-26, 05:51:14

Title: Very slow render + velocity pass not working
Post by: 3dkobi on 2019-06-26, 05:51:14
Hi guys,
So I made a scene with many screws + 1 HDRI light.
Gi solver is UHD cache, noise level set to 7%. The render is 1920*1080 pixels.
The problem is that each frame takes 2.5 hours on my machine (AMD threadtripper 1950X 16 cores\32 threads) - Does that sounds normal ? Maybe something wrong in my setup ??

and another thing - when I activate the velocity pass in order to make MB in post - the pass is completely black....

Peace,
Kobi
Title: Re: Very slow render + velocity pass not working
Post by: romullus on 2019-06-26, 10:28:15
I quickly threw similar scene just to look what would be estimated time. As you can see from screenshot, i got pretty similar time, but... this is on i7 4771, at least 4 times slower machine than yours. On threadripper i would expect 10-12 minutes for this scene. Maybe there's something wrong with your setup or materials?
Title: Re: Very slow render + velocity pass not working
Post by: 3dkobi on 2019-06-26, 10:55:46
I quickly threw similar scene just to look what would be estimated time. As you can see from screenshot, i got pretty similar time, but... this is on i7 4771, at least 4 times slower machine than yours. On threadripper i would expect 10-12 minutes for this scene. Maybe there's something wrong with your setup or materials?

Strange - in your scene you have about 1.1 million rays, and your noise level after the 6th pass is 23%
I had 2.2 million rays, now after disabling the bump map on the screws it's up to 5.5 million rays, but I have 63% noise after 6 passes...
I'm using only HDRI as light, and when replacing it with different HDRI i have the same render times. If I don't use hdri and just light mat on the sky object I get 10% faster rendering
The material of the screws is just dark gray diffuse and a layer shader with 2 textures for the reflections
Title: Re: Very slow render + velocity pass not working
Post by: 3dkobi on 2019-06-26, 11:04:33
Oh, another thing - my scene was pretty dark - yours is very bright - it takes much longer for noise to clean in dark places.
when my scene is more bright, and without the bump map on the screws I get estimated render time of 35 minuets per frame (it was 2.5 hours before)
Title: Re: Very slow render + velocity pass not working
Post by: romullus on 2019-06-26, 11:21:54
Bump always adds to render time, albeit 5 times sounds like way too much, but do you really need bump in this scene. I think glossy map should be enough, especially if it can save so much time. As for brightness, you can render the scene much brighter and change exposure afterwards. Again, if it helps to save time, then why not.
Title: Re: Very slow render + velocity pass not working
Post by: 3dkobi on 2019-06-26, 11:33:51
cheers
Title: Re: Very slow render + velocity pass not working
Post by: TomG on 2019-06-27, 14:37:48
Velocity Pass is not yet working in Corona for C4D, known issue, sorry. You can reference internal ID 217716749 if you want to follow up on progress at any point.
Title: Re: Very slow render + velocity pass not working
Post by: 3dkobi on 2019-06-28, 09:26:36
Velocity Pass is not yet working in Corona for C4D, known issue, sorry. You can reference internal ID 217716749 if you want to follow up on progress at any point.

Hi TomG - Wow, this is a big issue...It's a very important pass, without it we can't make good MB in post...I think you should put it very high on the priority list.
About the internal reference, where can I view this ?
Title: Re: Very slow render + velocity pass not working
Post by: TomG on 2019-07-08, 16:20:32
You can't view the internal tracking, but if you contact us about the issue, you can give that number so that we can pull up the information about it straight away. Thanks!