Noisy Render

[sdwhitton]

Hi everyone

I've attached a crop of a project we're working on currently - this has been rendered using PT, and to 10,000 samples, but still very noisy,
particularly the glass 'baubles' on the chandeliers - it's lit with an old Dosch HDRI, not too high res, but if I swap this for a flat colour, the noise
is still pretty much there - any ideas?

The glass on the chandeliers is just using the DB clear glass, and then the glass on the entrance door to the left is just a simple glossy material, opacity 40%

And then running on a GTX 470...

Wonder if I should take the glass elements out completely and render them in something else...

Many thanks

Stevo

[Magog]

When you use the HDR lighting and lots of glass is inevitable to have much noise. You miss the lights photometriche, and you have a bingo! For some remedies, try to use the pmc as the kernel, and try not to exaggerate too much with the roughness of the material ..

[sdwhitton]

I was going to do the feature lights separately - the bulbs within the chandelier were also causing too much noise too!

They are just spherical lights anyhow...

Will try PMC, and reduce the glossiness

would be a shame to have to go back to VRay or Mental Ray..

[sdwhitton]

sorted it, or compromised really - removed all glass, now it's quite happy

also, unticked that 'alphashadows' thingy - not even sure what is does, but that seems to give an extra 50% boost, performance wise

now just need to figure out how to render the glass separately.....

[roeland]

"alpha shadows" disables tracing of shadow rays through transparent materials, so a fully transparent material will still throw a shadow. If there are no transparent objects in the scene this will give a small speed boost.

Try putting a portal in the door and windows. This will make Octane render the light from the environment more efficiently. Have you tried PMC?

If you post an image to illustrate noise you should disable hotpixel_removal (set it to 1.0).

--
Roeland

[sdwhitton]

Hi Roeland

point taken about hotpixel removal..

there are portals, and haven't tried PMC as yet (think I would need a faster card...!)

here's the same render with the glass removed - think I must have also mucked about with the path-tracing settings, so I added a new one, and kept the bounces low...

so I think we're in business..!

[sdwhitton]

and then here's work in progress with the glass done in VRay (soz!)

not entirely convincing, and need to work out how to switch them on! But getting there hopefully

(I camera mapped the Octane render back onto the geometry...)

think, with all this glass, this image is obviously a special case, so no reflection (ouch! bad pun) on Octane at all, at all

think it's the best software out there!