R16 Reflectance render times?


#1

Has anyone heard any info how the new reflectance is going to effect render times?

I hope this info isn’t in some obvious place proving I’m blind.


#2

GSG said it increases render times slightly. Though if you aren’t using a Mac with dual Xeons it will be far less slight I guessing.


#3

And if you are using a pentium 2 it would be far less less far slight…?

What an odd way to answer that question. So many double negatives I actually am not sure what you meant?! :slight_smile:


#4

I think he’s saying that it’s not very noticeable on a Dual Xeon rig because it’s already very fast, whereas on slower chips (or fewer cores) it’s going to be more noticeable. Perception is subjective of course, and since Reflectance has no predecessor in C4D, it’s going to be hard to get any objective benchmarks to compare to.

I’ve heard it’s worse than slight, but we won’t know until we get hold of it. I suppose that’s to be expected when adding complexity, in general, things take longer.

cheers
brasc


#5

I’d hazard a guess that when using a single reflection layer with one of the new reflection models, it will be similar to the old reflections.

As you stack them up, feed more maps into them etc of course you’ll pay the price with render times. Similar to how you do with VRay or other renderers. In fact, I occasionally would use 1 blurred reflective material & 1 un-blurred reflective material, blended with an alpha under R15 to simulate variable blurriness & render times went up quite a bit.

Finally, if you go so far as to make even your diffuse materials in the reflection channel, then you’ll pay a high price in rendering time, more like using Maxwell or something. But this isn’t really going to be a recommended way to work most of the time.


#6

Rendering single reflection layer setups don’t differ much between R15 and R16 speed wise. Although for blurry reflections there are some differences because the sampler has been optimized for multiple layers. That means rendering two layers for instance will not double render times etc.

All in all I’m sure you will find the slight increase in render times for multi layer setups quite acceptable.


#7

Granted I’ve not used the r16 reflects nice but I’d assume if done right you shouldn’t need to layer two shaders for sharp and rough but a single with roughness driven by a map.


#8

Yes, that’s possible with the new Reflectance channel. You can drive almost every parameter with a map.


#9

" Rendering single reflection layer setups don’t differ much between R15 and R16 speed wise. Although for blurry reflections there are some differences because the sampler has been optimized for multiple layers. That means rendering two layers for instance will not double render times"

So blurred reflections and blurred transparencies aren’t fixed . . …
That sort of defeat the idea of reflectance.


#10

I don’t think it’s the matter of fixing it.
It was never broken, but was lacking of functionality like roughness map.
The other story is blurry reflections and transparency speed. It was always painfully slow compared to other rendering engines.
I was hoping that this time it will be at least 25-30% faster but it seems that it is now even slower, so my excitement about reflectance channel is brought down by it’s speed.
I won’t even star discussion abut nodal material system.


#11

What is broken? Are you talking about speed?


#12

Or rather debilitating lack of speed.
If you need to render a frosted bottle with blurred transparencies and reflections on a large part of your render you’re out of luck. Hopefully you don’t have to animate it.
If I remember correctly Vray isn’t handicapped that way.


#13

That`s true… And try getting rid of noise this side of hell freezing over :slight_smile:

[edit] I was referring to previous versions of C4D just to clarify.


#14

Just finished doing some stuff for the new Kate Bush show which makes decent use of the reflectance channel, worked perfectly acceptably for me. Speed-wise, it’s about the same as flipping on blurriness for a surface, but so long as youre not throwing in blurry surfaces reflecting in blurry surfaces and every other button you can think of to slow it down, it works perfectly fine.


#15

How bad is GGX render time wise?


#16

What is up with people and render times?

Like seriously, it’s not like it’s going to take 8 days to render or something.


#17

If you’re not concerned about render times, then good for you :thumbsup:
When people are trying to get a high quality product out and it costs them just +10% longer per frame, that’s potentially a big hit and less time to refine and overall, squeezes the schedule.

cheers
brasc


#18

Er…Depends how many Frames you are rendering… My last job involved 9 separate render passes. About 30 channels in total. About 20,000 frames…

Then it matters. I got my renders down from 45 mins for the main pass to about 6… Saved the company I was working for about 10K in render farming… did I get any thanks… Feck no.


#19

I’ve had plenty of jobs that run into week+ long renders.

Regarding GGX, theres very little difference in the render times compared to normal ones, but it is very much down to the settings you dial in. The more changes which blur or add grain to the image, the longer it will take to resolve them.


#20

Will your Architectural Interiors be updated to reflect the changes in R16? Or have an added video referring to those areas in the main video that could use the new functionality?