problems with caustix.

[tom schuelke]

Well,

i have noticed a bug with caustix and camera perspektive correction (shifter), which the caustix renderpass seems to ignore, so that the caustix get projected on the rendering in the wrong way...

away from this, i dont seem to get good caustix inside of my building.. they still seem to be very very noisy and i cant get them clean and smooth..

any idea what to change ?

ill put a short screenshot of my settings..


greetings Tom

[tom schuelke]

Hallooo...

anyone ? any ideas ? Just dont get it with my caustix.. why are they so noisy, what can i do ?

[Zdravko.Keremidchiev]

http://forums.chaosgroup.com/showthr...g-with-Caustix

Edit:
also to increase the quality of the caustics you need to increase the sun Caustics subdivs. Bit with the size of your scene that might take a lot more subdivs and it will be very expensive to render.

[tom schuelke]

Well this seems to be a small lack in the caustix rendersystem.... my sun allready uses 6000 Photons, which allready leads to loooooong calcultion times.

isnT there any other way to calculate smooth caustix in such big scenes ? I know for a glass of whine vray does a very well job. but for such bigger scenes , caustix doesnt seem to be very usable in production simply because the rendertimes seem to be very long.

never the less, ill look for my sun Caustics subdevis. maybe this will help me..

thank you

[M.Max]

Have you tried this workaround ? :
https://www.youtube.com/watch?v=F2c8cSArXnM
it is quick and give you the best control I guess with a good result
PS. this Sub-forum for "image upload" ,I think you have by mistake posted it here ..You can ask the moderator to move it the right place and you might have more/better suggestions there

[Svetlozar Draganov]

Well this seems to be a small lack in the caustix rendersystem.... my sun allready uses 6000 Photons, which allready leads to loooooong calcultion times.

isnT there any other way to calculate smooth caustix in such big scenes ? I know for a glass of whine vray does a very well job. but for such bigger scenes , caustix doesnt seem to be very usable in production simply because the rendertimes seem to be very long.

never the less, ill look for my sun Caustics subdevis. maybe this will help me..

thank you

6000 Photons are not so much for project with this scale, they might be enough for smaller scenes but for this one you will probably need more Photons in order to get cleaner result.
Caustics unfortunately are not so easy to calculate, their calculation is way more complicated than the regular GI and because of that they just need more render time.

Here are some tips you could try.

1.Set the Sun Photons radius to fit the current Camera View and not much of the details outside of the camera. This will ensure that all the Caustic Photos are fired at visible place instead of wasting time for photos are will never be rendered.

2.Once Caustics are calculated save their map to HDD, then load it and play around with Search Distance and Max Photons parameters. Except the Subdivisions those parameter could be also used in order to smooth out the result and the good thing about them is that they do not require to calculate the caustics from scratch and could work with already saved caustics map.

3.Disable caustics for the lights that should not cast such, they will only increase render time if caustics are enabled.