Animation Light Cache Setings

[gary_weller]

Hi. I have just upgraded from VRay 2.5 to 6. Historically, when rendering fly-through animations I would use irradiance map multi-frame incremental for primary and fly-through light cache for secondary. Saving the files for use with network rendering. VRay 6 has the same irradiance settings but the 'fly-through' for light cache is no longer listed. Is there an equivalent setting?

[^Lele^]

Welcome, Gary!

Those technologies have been phased out as they generated a few recurring, and unavoidable issues, and prevented the implementation of advanced methods that since then have been researched.
Notice that while the IRMap is still present, it's there only for the sake of compatibility, and the log prints a warning about it being on.

Render controls, including the GI ones, are now optimised by default, and we strongly suggest to change the least possible: simply changing the Lightcache preset from "Still" to "Animation" will take care of calculating flicker-free GI for sequences, regardless of what changed frame by frame (lighting, geo, cameras.).
Changing noise threshold alone will make renders go quicker, and noisier, or slower, and cleaner: subdivs tweaking on shaders and lights is gone.

To save time, instead, you'll want to look into denoising, the lightmix, adaptive lights and adaptive dome, and the adaptive sampler, among others.

You have quite a bit to catch up to since the days of 2.5, I envy you a bit.

[gary_weller]

Hi Lele, thanks for your reply

Yes, I'm a bit behind the curve, a lot to re-learn.

What would recommend as primary GI engine? I mainly do stills (usually 5500 x 3889) but sometimes fairly complex animations (1080p).

thanks

Gary

[^Lele^]

The defaults are already optimal in this sense: Brute Force as primary for pixel-sized, worry-free detail, and the LightCache to do all the heavy secondary lifting: it provides for 100 light bounces, it accelerates the BF calculations substantially (premultiplied light-cache) and as of 6.1 also for sample training for the Intel PGL, which when useful (it's scene-dependent) can be really useful.

For animations, simply change the LC preset to "Animation", and the LC will have more samples cast (to stabilise the solution across frames.) and the retracing (for when a sample isn't perfect) will be more aggressive (to avoid light leaks and the likes.).

Anything not working off defaults is then likely a bug, or scene-setup issue.

Speed is then controlled from one place only: the noise threshold in the sampler settings. Higher values will result in noisier quicker renders, and conversely for lower values.
Denoising then will take care of cleaning up the image.