OTOY Forums

Hi guys,
Trying out the latest 2.52. A test with hdri+mesh emitters

hola acelis, buen principio, practica el octanerender, es lo que te puedo decir
saludos

Gracias mil, en eso ando

The following points I succest you to improve/ test:
-Put only warm lights in the scene
-Make the windowsglass more reflective (use a glossy material with zero roughness and about 20% opacity) to see more reflections of the environment in it
-Put some warm lights into the interiors
-Use a HDRI with more saturation. Your HDRI has to mutch dark (black) colors which makes the hole image dark and "colorless"
-Some materials look very flat... give them a Bump or a slight reflection texture to make them "alive" or bevel (about 1cm) the edges of the geometries


Kind regards
Alain

Thanks a lot Alain!

Your recommendations are very valuable, I appreciate them. Will start testing them asap.

Kind regards,
Alvaro

Edit: Alain, one question. I'm getting a lot of fireflies that won't ever go away using a specular material for glass , with your glossy material setting for glass will they decrease a bit?

Alain, I tried your suggestions out. I added some emitters for the windows, changed the lights to a warmer temperature, added bump to several materials (though it's still not noticeable), and changed the hdri image I was using. I also changed to the path tracing kernel, and light's bouncing a lot more now. The result so far is this:

I like the effect, which is more accurate, but I'm also worried about the fireflies. Will they ever clean up, or is there a way to reduce them?


Thanks for any help in advance
cheers,
Alvaro

OK, things are looking better this morning

I'm a bit concerned because of the picture dimensions, In this small version (717x1024) the noise is reduced a lot, but the original version is 2645x3780 (almost 70cmx100) and will be printed, and noise is noticeable at that picture size. Though it's alot cleaner than the previous method I was using before, I hope it cleans the fireflies considerably.

cheers,
Alvaro

It looks mutch better now

In a scene of mine I found out that if you use a Glossymaterial for glass then you result in a stronger reflection as if you would use just a specular one.
I'm not sure about the fireflies, I guess in the newest Beta 2.52 fireflies are almost gone anyway.

Have look at some windows glass in your building. I looks like the glass is emitting light ? This looks wrong because at night if light is tunred on in a room you can see inside the room. So maybe you have to build a room behind those windows ?
Kind regards
Alain

Fantastic! Thanks a lot Alain, for taking the time to check and correct my image.
You have a sharp eye! I forgot to separate the back light of the car into another material so they're both white! lol. I hadn't even noticed that one!
About the windows, it's not that the glass is emitting light, I was checking some buildings at night and I noticed that even when they had their shades down, and the light inside was on, the effect is as if the shade became a mesh emitter (SSS?), so that's what I tried to mimick here; I placed several mesh-emitting planes randomly throughout (behind) the windows to achieve such effect. The problem was that I already had lights (by lights you mean mesh-emitting materials, right?) inside the apartments, and they're fully modeled (walls-wise) but they didn't fully illuminate the space inside, check the windows without a mesh emitter and you'll see what I mean. About turning some more off, I know there's a lot of activity going on at the same time there, lol, but I'm a bit concerned that if I turn many of them off the effect won't be as noticeable I'll make the suggestion to the client but I'll let him make the final decision.
About nowhereland (lol), what is usually done here? Model some boxes at different heights resembling buildings in the background? I'm gonna check some reference renderings on that one.

A quick question on the glossy material for glass (or better said, 2 questions). Does this material allow the passing-through of sunlight inside? And 2, the glasses in this project have a greenish tint in them that was possible using the specular material, can it also be obtained in the glossy material?

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

Once more, thanks a lot, it's always great to find a guiding/helping hand.

regards,
ALvaro

You should use a couple of hours in photoshop with an Object ID pass as your best friend to spice this up.
It looks very raw rendered.