KeyShot Forum

Technical discussions => Materials => Topic started by: ramizramo on January 08, 2018, 01:17:39 AM

Title: still could not find a good diamond material like the photo
Post by: ramizramo on January 08, 2018, 01:17:39 AM
Hi Guys, I am tyring to create diaomond material like the photo but I could not, I really like matrix stones material but I could not create like that. Can you help me for this? If you have material for haveing this quality I will thankful for that.

I am also added file if you can do something for having this quality, that will be perfect.

Ramo
Title: Re: still could not find a good diamond material like the photo
Post by: Frody on January 08, 2018, 06:23:01 AM
Hello ramizramo!
This is an old problem
Once I also asked myself a similar question.
At my request, the developer a lot improved the old diamond material
https://www.keyshot.com/forum/index.php?topic=10396.msg49599#msg49599
But still this material is not brought to the proper level.
I was just tired and did not at that time insist on further improvements in the material.
I tried to make a diamond like the picture you showed.
But I can not.
On your photo there is only pure blue blue black and green color.
All of them are clean and not mixed.
On my render, the colors look dirty. It is brown, dark yellow.
If you make a diamond separately and use HDR with blue and green, it can look like a foto. But then the metals will also be blue.
Sorry friend on me it seems that in Keyshot it will not be possible to do it. ((
A little frustrating that the Keyshot is positioned as a renderer for jewelry is why it is so difficult to make a beautiful diamond.

I attached a file with a ring.
Maybe I do not know how.
But someone will get it and he will tell us how to do it.
Title: Re: still could not find a good diamond material like the photo
Post by: Frody on January 08, 2018, 09:06:57 AM
The problem of the Gem material  is the wrong color reproduction with a low number of ABBE. If the HDR is black and white color then is a spontaneous mixing of colors among themselves and a dirty color is obtained. As a result of this mixing, brown dirty yellow and reddish shades begin to predominate
Title: Re: still could not find a good diamond material like the photo
Post by: KeyShot on January 08, 2018, 09:48:18 AM
You can see color mixing on photographs of actual diamonds as well. E.g.

http://www.epicmind.com/blog/2011/01/photographing-a-diamond-on-black

The lighting is key and camera angle is important to get clean dispersion. I recommend starting out with a simpler shape and no metallic parts to work on the lighting and and camera angle of the actual diamond.
Title: Re: still could not find a good diamond material like the photo
Post by: ramizramo on January 08, 2018, 09:55:23 AM

this answer was not helpful enough
there is no one who can get the ksp file we sent as photographed here please please
Title: Re: still could not find a good diamond material like the photo
Post by: Frody on January 08, 2018, 10:37:19 AM
@KeyShot greetings to you!
How to achieve that when using a black-and-white HDR map, in the diamond was dominated by shades of blue (without dirty brown dirty yellow and dirty red) ?
Title: Re: still could not find a good diamond material like the photo
Post by: Frody on January 08, 2018, 12:16:29 PM
A long time passed.
I did not follow it and could not respond in time.
Now it is closed and I can not write there.
I do not know whether I rightly publish my belated answer here ..
I think my answer will be relevant here.
If not, then moderator, please correct me.

https://www.keyshot.com/forum/index.php?topic=10396.msg52340#msg52340

Quote@Frody

Would it be possible to share your KeyShot renderings?
Can you share the model you used to render in Bunkspeed?

It would be great if you could help us match your results as close as possible. :)

I did some quick test rendering in KeyShot 6.
What do you think?

Dries

Hi Dries!
The material has become much better than it was in the previous versions.
But still needs to be finalized

All the same, there is a certain amount of turbidity and lack of detail.
At a low ABBE The colors mix with each other incorrectly. They do not correspond to the laws of physics.
Herein lies the main problem of not realism.

Below I am attaching two projects of the same product in different programs (Bunkspeed is now SOLIDWORKS Visualize) project in this program.
The material is configured the same. To see the problem at a low level, I lowered the number of ABBE to 5. The same HDR.

In the KS renderer, you can see that the blending of colors does not match the color spectrum. Hence all the problems follow. For example, between blue and red flowers there is dark purple (very dark almost black).
This does not happen in reality. This error is always present.
In SV there is no such problem. Colors are mixed correctly according to the color spectrum.
At any ABBE, the diamond always looks right. For any ABBE diamod always is clean. No dirty yellow and dirty brown.

Title: Re: still could not find a good diamond material like the photo
Post by: Frody on January 08, 2018, 12:43:23 PM
BS old
Title: Re: still could not find a good diamond material like the photo
Post by: KeyShot on January 08, 2018, 04:36:33 PM
We do of course use the correct spectrum for dispersion. I am not sure where you get your wrong spectrum idea from? I can see that you use multiple parallel linear lights in your environment, so overlapping spectra is to be expected.
Title: Re: still could not find a good diamond material like the photo
Post by: Frody on January 08, 2018, 07:42:31 PM
Maybe not a spectrum. Maybe it's something else.
How should I know? Just it looks awful and that's it.
I dont know what can influence the appearance for dirty colored.
But something influences.
Do not need be a great aesthete to understand. it's obvious.

I made two renders with both programs.
The same settings. Specially Low number ABBE.
The same map of the surrounding world.
I am attaching both projects.

Title: Re: still could not find a good diamond material like the photo
Post by: Frody on January 08, 2018, 08:05:59 PM
Here are photos of real diamonds. This is not a render.
It becomes obvious that SW render is quite capable of photorealistic. All the same colors and the same gamma.
Over the years, I've been trying to convince the Keyshot team of this...
Title: Re: still could not find a good diamond material like the photo
Post by: ramizramo on January 08, 2018, 09:33:39 PM

I believe that this problem can only be resolved in the following way
there is no one who can render the keyshot files we uploaded to the clipboard as pure and clear diamonds?
or we are pure and clean diamonds reder how do we say
Title: Re: still could not find a good diamond material like the photo
Post by: chicongds on January 09, 2018, 02:45:15 AM
This is render by vray in Gemvision matrix. It's not same keyshot
you can try do it by matrix software but can't render same in keyshot.

Thank you.
Title: Re: still could not find a good diamond material like the photo
Post by: ramizramo on January 09, 2018, 03:39:57 AM


I think KeyShot is a better render program, but KeyShot programmers have to help us
Title: Re: still could not find a good diamond material like the photo
Post by: KeyShot on January 09, 2018, 07:20:52 AM
Frody,

Thank  you for your feedback.

I took a look at your file, and I found a few issues that I think will help improve your rendering.

1) The environment map contains fairly large light sources, including one which has a brownish color?
    -> if you make the light sources (pins) significantly smaller and make them white you will see a cleaner spectrum

2) The background color in the scene is gray. This color is reflected in the diamond, which gives it a grayish tint.
    -> make the background black if you want to emphasize the dispersion

3) The diamond is rather large (10-11mm). It is perfectly white (no absorption) and with 24 bounces you will see a lot of overlapping spectra.
   -> To go for higher realism you may want to add some absorption (use the transmission color). You could for example lower the red and green a bit to get more bluish transmission if that is what you are looking for. The reason the default diamond in KeyShot is white is, so that it will easily work with geometry of varying sizes. We may customize this further to support for example yellow and pink diamonds.

These are just a few starting points. If you would like to further analyze dispersion in KeyShot then I would recommend to simplify the scene to a prism and a small light. For a prism the spectral output can be computed analytically and this can be used to verify the correctness of a given rendering.

KeyShot does use the actual physics to compute the dispersion. It uses a quadratic approximation of the variation in the index of refraction to compute the dispersion of light. This is the standard method for dispersion in the physics literature. The method is fully spectral (not just rgb, which would limit the colors to pure red, green and blue). The mapping from the spectrum to the monitor uses srgb, which does put some constraints on the available gamut, but I do not think this is an issue here.

Title: Re: still could not find a good diamond material like the photo
Post by: DriesV on January 09, 2018, 08:37:01 AM
Hi Frody,

Firstly, an Abbe number of 5 is very low. I don't know any material that has such a low Abbe number. A value between 20 and 30 is the lowest I know for glasses and plastics.

Secondly, which real-world references are you using for evaluating diamonds? Do you have actual physical diamonds to compare with?
It appears that many real and high-grade diamonds look quite muddy as well under normal lighting conditions.

Attached is an image of the priceless Koh-i-Noor diamond, one of the largest diamonds in the world.
You could easily achieve this in KeyShot.

Dries
Title: Re: still could not find a good diamond material like the photo
Post by: DriesV on January 09, 2018, 08:44:00 AM
If you really want high dispersion from your gemstones, then the lighting is very important.
You will want to use a high contrast HDRI, with multiple small light sources, without any color. Blurring the HDRI (in order to create a falloff for the light sources) will help as well.

Dries
Title: Re: still could not find a good diamond material like the photo
Post by: Frody on January 09, 2018, 09:20:43 AM
@KeyShot
Thanks for your detailed reply.
What you said is probably correct, but this long way.
Can you create additional diamond material? Conditionally, we call it "fake diamond".
Let in this deceitful material there will be such characteristics:

1.
Any environment map that contains yellow, brown or other colored sources. For the dispersion of this material will be converted into a monochrome black-and-white map. Let this material does not catch RGB from the HDR map.
Then we will exclude the appearance of dirt. We will only have pure spectrum colors.

Reflections from objects and from the outside world, let them be ordinary as they are now
Otherwise our diamond will not be realistic

2.
Let in this material there will be an additional option that would allow to regulate the power of the spectrum.( hue and saturation)
not excluding abbe number

3.
Let in this material there will be an additional option, to strengthen or muffle the colors separately.
Separately blue, separately green, separately red and yellow.

This will solve the problem that the topic starter said.
He needs the colors of the spectrum in the blue range and a little green

4.
Maybe it's worth thinking about the additional possibility of lighting an individual HDR for this material.
Let the environment settings be available.
Contrast, brightness, size, height.

Sometimes have to do two renderings for a single product.
Separately, render and customize the metal and separately already another diamond another HDR
Then combine the two renderings in Photoshop

Maybe this material will give impetus to the development of new materials with more advanced settings.

If you can implement these simple options.
Then Keyshot will not be equal in the market.
You are will find yourself beyond competition.
To visualize diamonds accurately.
Title: Re: still could not find a good diamond material like the photo
Post by: Frody on January 09, 2018, 09:34:06 AM
Hi Dries.
For a long time I worked at a jewelry factory
I worked with Yakut diamonds weighing up to 17 carats and I know what I'm talking about.
Yakut diamonds of the highest quality and color and lack of inclusions. Characteristics 1 1 is the highest quality. Transparent Without dregs.
In sunlight, it shimmers with all the colors of the rainbow. That's very beautiful. As if you have a multicolored flashlight in your hand
Title: Re: still could not find a good diamond material like the photo
Post by: ramizramo on January 09, 2018, 10:12:27 AM
Frody
you are super
Title: Re: still could not find a good diamond material like the photo
Post by: ramizramo on January 09, 2018, 10:15:52 AM
KeyShot and Dries, Frody is right; We belive that keyshot can take this quality render, just waiting exactly result from you as material. If you check matrix gem materials they all perfect!

We are waiting you from the same material for haveing same quality! I hope more than Matrix maybe!

Title: Re: still could not find a good diamond material like the photo
Post by: KeyShot on January 09, 2018, 01:40:32 PM
Frody,

We will consider your suggestions. I can see that an artistic approach could simplify the process when you are trying to achieve a specific look.
Title: Re: still could not find a good diamond material like the photo
Post by: Frody on January 09, 2018, 03:49:50 PM
Thank you.
I will hope that you will succeed.
And probably the new material will be called GemArt :)
Title: Re: still could not find a good diamond material like the photo
Post by: ramizramo on January 10, 2018, 05:30:36 AM
if you create a new material from the graph, we would like you to download this recently refurbished material here.
Title: Re: still could not find a good diamond material like the photo
Post by: ramizramo on January 10, 2018, 09:44:10 AM
I still coulndt understand, experts and modarator say that you can take this render . I am saying that please take for us and upload in here as ksp file. We need just matierial and hdr for that. If is possible please show us.
If not say us please, sorry its not possible and we stoped to spend our time ....
Title: Re: still could not find a good diamond material like the photo
Post by: ramizramo on January 12, 2018, 12:47:56 AM

If I were the owner of the keyshot, I would have kicked out the entire management team.
no one helps
What a pity
Title: Re: still could not find a good diamond material like the photo
Post by: Esben Oxholm on January 12, 2018, 04:28:53 AM
Quote from: ramizramo on January 12, 2018, 12:47:56 AM
If I were the owner of the keyshot, I would have kicked out the entire management team.
no one helps
What a pity
Lol. Way to appreciate the time people are using trying to help you. I was about to look into possible ways to achieve this specific look that you are after, but now not so much. Based on your reply here, I feel that if the result isn't giving you an exact ready-to-go solution, you'll see it as unhelpful. This attitude will get you no where on this forum.

Cheers,
Title: Re: still could not find a good diamond material like the photo
Post by: ramizramo on January 12, 2018, 06:03:43 AM
esben
KeyShot needs to provide us with a service
Instead of offering me the solution directly
they would say
and the recommendations they give do not work
we want the result
Title: Re: still could not find a good diamond material like the photo
Post by: mattjgerard on January 12, 2018, 06:14:24 AM
Quote from: ramizramo on January 12, 2018, 06:03:43 AM
esben
KeyShot needs to provide us with a service
Instead of offering me the solution directly
they would say
and the recommendations they give do not work
we want the result

And the result that you want is a result of the work that you put into it. There is no turn-key one button solution to your challenge. If they have the answer to your problem, then they say it. The Keyshot team has never held back solutions for any reason, they go out of their way to help their clients achieve what they need. I've seen it happen dozens of times. Throughout this whole thing your attitude has been combative, accusatory and downright disrespectful. Its been embarrassing to watch, frankly. I applaud Dries and the rest of the team who have actually been trying to explain and help.  Since you aren't getting the answers you want, instead of just understanding that the software may not be giving you exactly what you desire maybe you can be looking for a software that will.

I also know that my renders are rarely done 100% in keyshot. I'm certainly no expert in this area, and I'm not sure if this is the answer, but Any other image you see out there from a 3D program used in marketing and advertising has not come clean out of the rendering package and onto a brochure, billboard or website. They all get massaged in photoshop. Might that be an option for you? I've learned a ton about color manipulation in PS from my time on this forum.

Anyway, good luck to you, I sincerely hope that you find the answers you are looking for, but I will be following Esben out the door.
Title: Re: still could not find a good diamond material like the photo
Post by: mattjgerard on January 12, 2018, 06:16:11 AM
Quote from: ramizramo on January 10, 2018, 09:44:10 AM
I still coulndt understand, experts and modarator say that you can take this render . I am saying that please take for us and upload in here as ksp file. We need just matierial and hdr for that. If is possible please show us.
If not say us please, sorry its not possible and we stoped to spend our time ....

And that large diamond looks fake as hell, to be honest. really  subtracts from the look of the rest of the piece in the wider pictures. the straight on closup looks like it was done in illustrator.
Title: Re: still could not find a good diamond material like the photo
Post by: Frody on January 12, 2018, 01:08:47 PM
ramizramo
Indeed, why are you so?
It was necessary just to have patience and be a little more polite. And maybe someone would be able to do what you are interested with based existing material.