Micro-scratches with vrscans

[MANUEL_MOUSIOL]

Hi,

I am working on car visual right now and would like to bring in some subtle micro-scratches to the surface for added realism.
Now with a normal vray material I would add several layers with different IORs on top of my car material that have these scratches in the bump slot, so they are only visible at the right angles and lighting. These add to the clearcoat obviously, which wouldnt be a big problem with a normal material since I can just switch off or dial down the clearcoat underneath.
But with vrscans there is already the bump included in the clearcoat, which I obviously like to use. But if I layer the scratched materials on top the coat is too strong and the vrscan bump will loose its weight.
Putting the scratches into a bump material is not possible since the car will look too damaged.
Is there a possibility for my endeavour?

[Ivaylo Katev]

The "strength" parameter of the clear coat allows mapping, however is not yet in the UI.
But it's not a bump, it makes the clear coat reflection to be less or more pronounced, i think the real scratch is more complicated, since it can look white under certain view, so may be you have to disable the embedded clear coat and to prepare you own layer with all the bumps you need.

[MANUEL_MOUSIOL]

yeah, I thought so. But it would be great to plug in the bump of the scan into my own material, so I dont loose that. wouldnt that be possible in general?

[Ivaylo Katev]

You mean the clear coat bump? Because we have separate clear coat and base bump.
Btw what if you just put the vrscan material in a vray bump material? I think for scratches you need very thin bump, that will not affect the base material, so it can work.

[MANUEL_MOUSIOL]

So the clear coat doesn't have any bump ?
I only want the scratched to be visible around where bright lights are hitting, just seeing the highlights, as you would see in real life .if I put it in bump the car looks very scratchy...

[Ivaylo Katev]

It has separate bump, that's why i asked for confirmation.
Btw what a texture are you using when preparing such scratches using vray mtl? I should say we was considering an idea for scaned material that modifies random surface, sort of highli transparent material that can be put in a blend material (or in some dedicated slot of our material) to achieve the desired effect. The idea came when we had to scan several materials with and without dust on them, the dust has similar appearance on any surface and can be extracted as separate material. Perhaps the same approach can solve your problem too, may be we must try this.

[MANUEL_MOUSIOL]

using the normal map variation of this here.
that idea you proposed sounds great! more flexibility with vrscans would make them even better, especially with surface imperfections. For example I love the rubber material because it already has these imperfections built in.
I think Grant Warwick was talking about that he asked you to scan fingerprints and dust and he is using these. Looked for them in the library, but apparently it is only for him? Maybe you can upload them? Would love to use them! How would you actually combine those with another vrscan?

I am having trouble getting these scratched materials to be less noisy btw. Dont know if I have to blur the map (its pretty highres though) or do something else...having the hope the vrscans would give me a better expierence. see the test rendering attached.

[Ivaylo Katev]

We have scanned some dusty materials for certain customers, but we still have no general purpose dust material, because the scanning technique is a bit tricky.

[MANUEL_MOUSIOL]

so what does it look like? or what seesm to be the problem? tiling? would love to take a look and give feedback if you like

[MANUEL_MOUSIOL]

recently no updates to the vrscans library. any news on what is planned to be scanned? what about those dust materials?

[Ivaylo Katev]

The dust materials are still not implemented, we have to finish some tasks with hogher priority first.
I have no idea what is planned to be added to the library, but if you have some prefferences, tell us, we will try to find samples and scan them.

[MANUEL_MOUSIOL]

Right here, right now? Or shall I write an email for organizing purposes?
A pure hologram (just color, no logos or designs) would be great.
Right now the library is full of "professional" materials, but I would love to see some more natural ones, like the leaf sample. Rocks, natural wood, concrete, different kinds of papers etc...

[Ivaylo Katev]

Yes, here is good, no need to write a mail.
A "pure hologram" is something that i can't even imagine the CD looks like the nearest real example, but it still has anisotropy, can we consider it pure enough?
Rocks - i just collected some samples in the mountain, exactly with the idea to scan them. But i think we have to find bigger samples, these are small and i just want to test the ability to represent sparky materials (the samples are rich of mica).
Natural wood - can you post an image to clarify what it should be?

[MANUEL_MOUSIOL]

A CD would be cool, but I was more thinking about paper:

https://german.alibaba.com/product-d...e1edcZLN2g&s=p
https://naehzauberei.de/out/pictures...-hologramm.jpg
https://de.depositphotos.com/1890100...ram-paper.html

What you have right now are holograms with patterns

https://download.chaosgroup.com/vrsc...ram-100-euro-s

If you could scan a pure holographic paper, then one could introduce a self-made pattern.

for stones here are some examples:

https://de.dreamstime.com/lizenzfrei...-image33506445
https://www.google.com/search?biw=25....0.VDyHqdZYkGc

the sparkles in the stone material would be great!


attached is some wood. something raw but not too raw when compared to a living tree for example.


BTW, what exactly is the highes resolution you can scan?

[Ivaylo Katev]

Heh! First time seeing such a paper, the item is described as "for gifts", so hopefully we can find some pieces in the dedicated stores
Well, i will talk with Mitko who is in charge to see what kind of materials we can find and scan. The resolution limit is 850 dpi,in the most cases we scan in half resolution in order to have lower file size.