Building - Sunrise

[Alain]

@alvaro
maybe your glass has to mutch roughness (turn it to zero) ? This could be the reason why it looks like a sss material.
Use the PMC kernel and fireflies should go away. Or turn on "Fireflies reduction" in Octane.
23 hours seems to be a very long rendertime, I normaly have better results in a shorter amount of time.

In PMC or PT you can reduce the "Bounces" (can not rememer how it it's called exactly) from 16 to 8. It make the rendertime shorter and quality is still good enough.

There is a Photoshop plugin called Topaz Denoise to reduce noise (fireflies) which should also work for Gimp, see here:
http://www.pentaxforums.com/forums/digi ... -gimp.html

Isn't there a plugin called "citymaker" (or something similar) for Blender ?

I'm always glad when I can help

Kind regards
Alain

[afecelis]

@[gk] Thanks for the info, I'm not a Photoshop user but I'd be interested in reading about the concepts you mention. Do you have any links or tutorials about it?

@Alain: My glass has roughness set to zero, what I meant about SSS was the effect of a curtain behind it receiving light, which is what I have, a mesh emitter the same size as the window behind the glass Unfortunately, I used Pathtracing as kernel and spent almost 30 hours rendering! lol What difference does PMC make over the other kernels?

Thanks a lot for the denoiser plugin for gimp, I'm checking it out right now. And thanks for the city plugin suggestion, it's called suicidator city engine:
http://blenderartists.org/forum/showthr ... -coming%29
I'm also checking that one out.

Gonna run some tests on the PMC kernel to see how things go, obviously on a smaller size.

regards, and thanks for all the comments and help,

Alvaro

[[gk]]

Look up anything regarding mattepainting, that would solve your background, the lack of transition, missing details in interiors. sterile big surfaces.
You have a somewhat nice foundation but you need to work in a 2d app to make it nice and thats not just color calibrations.
Multiplying random bitmaps over surfaces, using masks, using photographs of interiors for the windows etc etc.
Its a whole other game that hacking out pixels from a render, so be prepared to meet a new world, a world that will lift any archvis to a place no render can ever achive.

[afecelis]

Thanks [gk], somehow you make it sound interesting and exciting, yet also a bit intimidating... challenging!
I'll check info on your suggested topics.

regards,
Alvaro

[Alain]

@Alvaro

Put the light emitting plane on the ceiling of the room and not directly behind the windowsglass because this is the old Biased Renderer method .

For my part I have the following definition of the kernels:
Directlightning: Very fast, a very good but not a perfect renderresult.
Pathtracing: A physical correct renderresult, no so fast as Directlightning, fireflies can apear (but I'm not sure if this has been fixed yet).
PMC: A physical correct renderresult, no so fast as Pathtracing, fireflies almost completely disapear.

Kind regards
Alain

[afecelis]

Cool tips Alain, thanks

And cool explanation of each kernel. I'm going to try a version with the mesh emitters on the ceilings and check out the results.
I'm learning a lot through this experience, thanks a lot.

regards,
Alvaro

[StompinTom]

About fireflies, I don't know if it's because I'm using the PT kernel, or because of the glass/glossy material change, but in the previous version the render finalized the 16.000 samples in 23 hours and stopped and it was still noisy, in this version I'm on 8600 samples/32 hours and it's a lot cleaner, and still has samples to go, as if it could dedicate more time and efforts to clean up the noisy parts, funny but lucky

If you're spending over 24 hours rendering a simple scene like this and it's still very noisy, I don't think Path Tracing is the right route to go. It's scenes like this where the 'GPU + Path Tracing' versus 'CPU + Metropolis' tradeoff becomes very apparent, unfortunately... Spending 24 hours on a single image of that resolution defeats the purpose of fast GPU rendering and is unreasonable

[afecelis]

StompinTom, you got a point there. Perhaps a traditional raytracer might have given me quicker/cleaner results, but the physically-correct part of Octane makes it so tempting to use!
Don't know if it would've been as straightforward to achieve the same night ambiance with a raytracer, or if it would've required lots of tricks to succeed. In fact, I made some tests of the same scene with yafaray using its night sky model and results weren't what I expected

Yet it's still ironic to see advantages of cpu vs gpu rendering in some specific tasks.

thanks for commenting,

Cheers,
ALvaro

[[gk]]

its not ironic, its logic

[afecelis]

heheh, yup, you´re right, the ironic part is having 300/400/500 or more cuda cores available and not getting the job done