Kerkythea Rendering System

Hy render dude! I've got a quest for all the expert

Sometimes when i use default glossy, shiny or brushed materials (like metals, mirrors...) on some borders i obtain strange artifacts reflection (see image below). I tried to follow the also know and useful tutorial "sparkles, black and white dots, noise on materials?" without any improvement

Could anyone help me?
Thank's for supporting!

I'm not sure is an artifact as it rather seems a reflection. Could you share the scene to check it?

Grazie 1.000 Tridem
Waiting for your suggestion.
Don't know if would help but I observed that it happen "always" with closed view (even with big re-scaled model) and there is no difference if the faces are perfectly "touched" or separated

ok, guardando più in dettaglio c'è effettivamente un artefatto oltre ai riflessi molto accentuati dovuti al materiale.
Ho comparato diversi metodi e si nota che MLT e BPT risolvono meglio, mentre photon map e path tracing evidenziano le fessure luminose.
Per come la vedo io è un problema di volumi non chiusi capita spessissimo con sketchup, cioè le facce sono perfettamente adiacenti ma vengono comunque viste separate e non unite, infatti ho provato a dare da KT il comando weld vertices e le cose cambiano.

At a deeper look there's indeed an artifact, apart from the very bright reflections which are due to the material.
I compared several methods and you can notice that MLT and BPT can solve better while Photon map and path tracing have those lighted cracks.
IMHO is rather a modeling issue related to unclosed volumes, it happens very often with sketchup to have faces perfectly bordering but actually not united, I tried the operation weld vertices within KT and it seems working good.

Ok grazie ancora! Ma ti chiedo:
1- c'è un procedimento più corretto in SU da seguire per evitare a priori questo problema durante la modellazione?
2- intendi "vertex welding"? come lo si utilizza? funziona on/off o qualche variabile?
A questo punto, volendo applicare una materiale estremamente specchiante (cromo lucido) c'è una tecnica più intelligente per ottenere un risultato più realistico?

Ok, thank's a lot! But:
1- is there a more proper way to model in SU in order to avoid this problem?
2- you mean "vertex welding"? how does the command work?
In this way, i had to use an extremely reflective material (like chrome metal): is there some other tips to obtain a shot more realistic?

I made some other test with different materials... after all, it seems more likely a smoothing issue than of vertex welding
anyway I'm pretty sure it's related to the geometry, the gloss material just emphasise the matter.

I cannot give you advices on how to avoid strange behaviours of the sketchup's model except working very clean without messing the objects

as for improve realism for reflective metals, I think the most important thing is taking care of the details - for example always bevel the edges (as perfectly sharped edges doesn't exist in real world!); rounded edges perhaps would be more accurate but it's quite difficult then to manage the normals and it increases the model dimension - I believe a simple bevel do the work