comparing flakes from stochastic and axf scan of carpaint

I thought i would bring this up for discussion, i love the control of stochastic flakes to build a car paint material however i have recently installed AXF plugin and been given a scanned paint material, the difference in flake is night and day when comparing scanned shader vs trying to build it again with stochastic material. I have always been a little frustrated with stochastic and flakes when rendering a whole car the flakes are either too big and slightly blurred, make them any smaller and they disapear or just become noise. I can never get a flake to be a sparkly bright single pixel.

Is this just a limiation with stochastic and or maya, what are other peopls thoughts? anyone else done a comparism or got close to a scanned material?

Im rendering in maya 2022 and vray 5.2

left stochastic , right axf scan

thoughts and discussions welcome

thanks

matt

My results also look like the render on the left. I have managed to match a photo of car paint on a close up swatch, but never gotten the sparkle variation on wider shots. Also that level of clarity of the flake on the right side render looks great.

The VRayCarpaint2 material should be able to produce similar results to AXF, but I’m not sure about the stochastic flakes material tbh. If you post a scene with just a sphere under some suitable lighting and rendered with both AxF and stochastic flakes/VRayCarpaint2, then we can try to match them.

Best regards,
Vlado

You need to layer multiple Stochastic flakes materials for best results, I usually use 2 or 3
the topmost layer is smaller flakes, less in distribution..

https://cdn.discordapp.com/attachmen…mage_58420.jpg
https://cdn.discordapp.com/attachmen…lakes_001.jpeg
https://cdn.discordapp.com/attachmen…lakes_001.jpeg

The first render is carpaint 2 material with these settings


I still prefer stochastic flakes for the color variation controls

Best,
Muhammed

@Muhammed_Hamed

thanks for posting, What are your AA filter type and size set to in those renders im having some success lowering my filter size to 1.5

@vlado

i have made a simplified scene but cant make it public as AXF Material is under NDA , where should i send it to

thanks

matt

I updated my screenshot above, for VrayCarpaint2 Flake glossiness of .9 to .95 will give you the needed sharpness
There is no need to use AA filter to get sharper flakes

For Stochastic Flakes, here is an example setup, you need at least 2 layers of flakes in a blend material. They are different in Blur Angle
I also added color variation to the smaller flakes

If you are using Maya, you can download both my examples here

@Mattheo999 please submit a request here
Or send it to my Email, muhammed.hamed@chaos.com

Best,
Muhammed

Hi @Muhammed_Hamed ill get you a test tile that i have been playing with over email asap, just runing some comparism renders, vray carpaint 2 vs axf vs stochastic.

thanks

matt

What are the results?

sorry got bogged down in work and didnt send a file to muhammed have done now

cheers

matt

Sorry to piggyback this tread - but I’m trying to import an Axf file in to V-ray 6 - but the plugin I’ve been given only works on older versions. How are you managing to import the AXF?

I’m on vray 5.2 no idea if it works in 6. Sorry

Thank you for the scene file @matthew999

We are looking into this now