Facade

[Robert G]

Hello all,

I’m working on this façade.
I’m getting close to what I want, but as you can see there are some problems.

http://download.video-for-pearls.nl/CompSmall20-11artifacts%20copy.jpg

Any idea what is causing these dark “clouds”?
Tried many things without success.

Thanks

Robert

[glass.use]

increase the values of the IR
Hemi subdv, and Inter samples to higher value.

or use the very high quality preset and see.

or maybe the brick texture have this spots? make the texture default white and see.

[Robert G]

Thanks glass.use.
Well its exactly what I did, without any improvement.
I'm trying again, I used 70, 30. Maybe not enough.

Thanks for now.

Robert

[glass.use]

use 100 - 55 :wink: and show me the result. :wink:

[Robert G]

Thanks glass.use. So it seems I did not use high enough values.
Much better already with 100,50.
This is rendered at 1022*768, the final image will be rendered three times as large, am I correct thinking that I can use smaller values in that case?
Thanks again.


Robert

http://download.video-for-pearls.nl/CompSmall20-11artifacts.jpg

[glass.use]

better now but im 100% sure that the texture itself have some black spots. and it looks natural no brick is clean.

[Nico]

I think it's not black spots but it's a noise bump. If Robert G decrease the scale off the bump it will more real, even if the noise bump is erase.

[osergios]

cool man !!!
can you show me some directions about how to integrate
a real picture in my scene ? like yours ?

[Robert G]

The magic word is,.............. Photomatch a plug that calibrates your camera to the picture, there are some nice tuts aswell explaining all you need to know.

Kind regards, Robert

[Robert G]

I made a little update, with new setting its much better, but as you can see,.. still some problems.

http://download.video-for-pearls.nl/Comp3.jpg

HemspSubD. 180, Interpolated Samples 100.
This seems quite high to me already, do I need to change the various thresholds?


Thanks in advance, Robert

[osergios]

many thanks robert ...
and by the way i think the solution for yor problem is to use lower hemispheric subdiv than interpolated samples
something like 70 /80 or so
in order to reduce the artifacts try increasing only interpolated samples
the hemispheric subs are enough ....
hope i've helped.

[ZuluQ]

Robert G, i dont know exactly what u want to achieve, but honestly for me was hard to tell what is a model and what is not, great texturing, great integration with the environment, great lightining.

I'll work a little more is the saturation of the couple in front of the building, they dont look like they were covered by the shadow, and the purple colour of the skylights, i think that dont match the rest of the composition, but its only a matter of taste.

Nice work!

[Fluffy]

If you increase the interpolated samples too much, you will lose all GI definition in your render (the GI samples are smoothed and interpolated together, which means less artefacts, but more "blurry" GI).
I think you should lower that value, increase the hemispheric samples (number of samples shot for each light source and bounce), and increase the sampling rate.
What is your secondary engine? Increase the number of samples as well.

Very natural light and great integration, otherwise. I don't like the windows on the roof, though, they stand out too much and need their materials tweaked (glass and purple color as well).

[Robert G]

Thanks Osergios, are you sure you don’t mean it the other way around, higher hemispheric subdivisions and less interpolated samples?

Yes you’re right zuluQ, they don’t match, actually I tried something like you suggested, but it did not work very well. Maybe I should give it another go.

Fluffy I tried what you suggested, I now have HS 250, IS 70.
Still I got this result.

http://download.video-for-pearls.nl/test0063.jpg


Seems a little better but still unacceptable.
What do you mean with increasing the number of samples, the Max rate in the image sampler?
Secondary engine is LC.
I agree with you on the roof windows, will try to change it if I have time enough.

Thanks guys for your comments and help so far.

Kind regards, Robert

[Fluffy]

Yes, I meant the min and max rate of samples.
This will increase the number of samples placed on each surface, and will get rid of artefacts, especially where geometry is close together or intersecting, as it will place more samples in these areas.
It's sometimes tough to find the proper balance of GI samples and smoothing to get a good result without too much of an increase in render times.

If this still not helps, try a completely opposite solution : lower your GI solution a lot, and smooth the hell out of it. Then turn On the details enhancements of the IR map. That way, you will get your smooth GIs that will render blazing fast, but the details enhancements will add a sort of AO pass and increase details where objects are close together.

[osergios]

no i meant what i 've said try it and you will see.

[Robert G]

Well things became a little better, it helped quite a lot to fix some intersections of the doors.

http://download.video-for-pearls.nl/test4.jpg

I still have some nasty distortions as you can see, seems AA problems to me: because if I zoom in on that area, it looks good.
I raised the value’s of the Adaptive Subdivision to -2/ 8.
Did not help at all, so it must be something else.
Any suggestions what to try next?

Thanks in advance,

Robert

[Fluffy]

Do not undersample. Use a Min value of 0 or 1 at first, and see if it fixes things. Lower the threshold if you still haven't got staisfying results with these values.

P.S: I think these are still GI artefacts. You might want to activate Details enhancements and lower your GI settings as well (details enhancements does a sort of AO pass, but it also takes into consideration light diffusion).

PS2: Why lose too much time fixing such tiny artefacts? Just brush it up in Photoshop. 10 minutes, done.

[Robert G]

Thanks Fluffy,

Will try you suggestions.
Yes, Photoshop is a good option, might end up doing that.
But its also because I want to understand whats going on with Vray.

Thanks again, Robert