the ''4 meters'' render issue

[lef]

hello guys !
I need to make a huge exterior render for a 4 meters poster (it will be printed)!
the model is about 11 million polys (6core i7 6850k & 32 gigs of ram), I have no crushes but the process is
(obviously) ultra slow !

At the beginning I thought that 72dpi it would be ok for the printed poster  so the width of the render came about 11500 pixels, the initial render pass took like for ever and I have to cancel
the process and now I am rendering 9000 pixels (56 dpi) but the initial pass  already took 3 hours and it's not yet finished , maybe needs one hour or so to finish ...

what can I do to make the render process faster ? It's about the polys ? if I make some proxies it will be faster ? or is the size that causing this delay ?

thanks in advance !

[lef]

I know it's English .. :p

[FrostKiwi]

Show your RAM usage.
The mega resolution is probably killing your RAM and as it pages to disk your speed is gone.


You can use Backburner's Strip rendering to render the Image in 1000px thick strips.
Then the exported EXR can be fed into the corona image editor to do your glare and stuff.

Although denoise and lightmix won't work afaik.

[lef]

Thank you SairesArt for the reply!
currently I am trying to reduce the polygons as much as possible (proxies)
and I will try the 'strips' method you recommend !

[lef]

with alot of proxies , a reached the 350.000 polys in total (vertices 3 million)!
but nothing changed , everything runs very slow ! and the ram usage is 90-95% !

the strip method is very slow too ... damn, I hate the tight deadlines ...

[romullus]

Try to minimize number of unnecessary render elements - those can be real RAM eaters at big resolutions.
Also, there's 37M triangles in your scene and whooping 10M instances. Most likely, that means that your grass is scatterred as single blades, not sure about RAM consumption, but i think it's hurting scene parsing times and overall performance too. You'd better attach grass blades in to bigger clumps, so that number of instances would be more manageable.

[lef]

thanks romulus I ' ll try that too !

[maru]

Check this guide out: https://coronarenderer.freshdesk.com/support/solutions/articles/12000023310

[lef]

so...I deleted all the elements and all the proxies not visible in the scene and reduced the ones that remained
and I can see an increase of speed like 60-70 % !!! now I am rendering in 12k !

thank you very much for the tips , God bless you all ! :)