Render Speeds. Tips on Speeding things Up

[wardy_mk]

Hi everyone.
We have to churn out a lot of renders here. Are there any tips you people can suggest to help me and my colleagues speed things up at all? Materials / Render settings etc? Other than going out and buying new computers of course...
Any suggestions would be greatly appreciated.
Thanks in advance

[Beanzvision]

What kind of images are you expected to churn out? Do they contain displacement, SSS, hair, volumetrics? These are things that can increase render times for example.

[maru]

Here are some things you can do to get faster rendering at the cost of quality and realism:
- Enable denoising - https://support.chaos.com/hc/en-us/articles/4528591107729-How-to-use-denoising-C4D
- GIvsAA balance - lower value = better anti-aliasing but more noise; higher value = worse anti-aliasing but less noise within the same given time
- Light Samples Multiplier - lower values = faster rendering but more noise in direct lighting
- Max Sample Intensity - lower values = faster rendering but darker GI
- Max Ray Depth - lower values - slightly faster rendering but less reflections, refractions, and GI bounces
- Disable the caustics solver
- Enable the Dof Highlights Solver if you are using DOF
- Highlight Clamping - 0 means disabled. Low values = darker but faster rendering. This removes high dynamic range from your output so never use this if you care about high dynamic range (things like saving images to 32-bit files).

Just keep in mind that we don't recommend changing render settings from defaults, and definitely do not use extremely high or low values. I would halving them (for example try with Light Samples Multiplier set to 1 instead of the default 2).

[wardy_mk]

@BEANZ
They're retail displays mostly. For fragrances. Sometimes displacement, most times not. Actually rather simple stuff. Very little SSS or hair. ...

For a 210x297mm @200dpi image it's taking a minimum of 3.5 mins per frame.
Does that sound slow? (obviously this is a 'how long is a piece of string" comment).
Attached is an OLD render done in normal standard render. Will show you the kinds of things we do though...we've moved on technically and creatively since these were done (more than 8 years ago)....

:)

[TomG]

dpi and image size are irrelevant for renders, only pixel dimensions. So do you mean you are rendering 1,654 x 2,339 pixels? (which is what https://pixelcalculator.com/en says those mm dimensions and 200 dpi would be in pixels).

[wardy_mk]

Well it's simple maths isn't it? 200dpi at A4 size gives you an amount of pixels...

[TomG]

Right, so what IS the pixel dimension you are rendering to, as that is what determines render speed :)

[Beanzvision]

From this test render and a noise level limit of 4%, it was roughly the same. Other than what my colleagues have mentioned, you could also use Corona bitmaps to reduce render times.



As for DPI, this video is handy:

[wardy_mk]

Oh no worries, I'm 100% all good with resolution and whatnot. I've been involved with digital design for 29 years! I don't know what the resolution is off the top of my head- I just use the box on C4D. We used to render them out at 150 and upped it to 200 recently that's all. In case someone wants to print one off. :)

[maru]

Just to solve the mystery: the resolution is printed at the top of the VFB window :)

[wardy_mk]

Handy!

[TomG]

Aha mystery solved :) It does sound reasonable as a time-per-frame in that case - though would need to know what CPU and RAM the machine has to say for sure.

[wardy_mk]

No worries! My computer is a Mac Studio with an Apple M1 Ultra in it with 64GB Ram,. :)

[TomG]

TY! Does indeed sound like reasonable times to me in that case - as in, nothing is broken there. Might always be room for some scene-specific tweaks for a little improvement but overall everything on track!

[wardy_mk]

Thank you sir!