Solved: vray rendering problem

Anonymous · ‎04-22-2017

my question is why material like this? the black part on the top. how to erase black color? is my shader is wrong? help me please. i'm a beginner. thank you!

Alfred.DeFlaminis · ‎04-24-2017

Hello @Anonymous,

I have moved your post out of the tips and tricks thread, please make a new thread if you have a Max question and I will do what I can to help. It's better to direct Vray questions to Chaosgroup since Autodesk doesn't make Vray, but the reason you are getting a black area on top is because your environment color is black. Use an HDRI or something in your environment slot or in the reflection override slot in your Vray environment settings to remove this black area. Since your world is black, it's reflecting and refracting black.

Please hit the "Accept as Solution" button if my post solves your issue or answers your question. This lets me know that I was effective in helping you, and thank you for doing so.

Best Regards,

Alfred.DeFlaminis · ‎04-25-2017

Hello @Anonymous,

I just wanted to follow up here, any progress on this issue?

Best Regards,

kgokhangurbuz · ‎04-26-2017

Hi;

There's nothing wrong with your material. It's the background (Environment / space) color of 3ds Max which is black, being reflected by your glossy material. (You can confirm this by changing your environment color to red and re-rendering the scene, you'll see what i mean).

Regards;

Anonymous · ‎05-04-2017

my problem is still not solved yet. i use the chrome material. but it's not my expected. what's wrong with it. i try everything. but it's not working. so i try to get some help in here. waiting for the exact answer.

MarcoG67 · ‎05-04-2017

Hi,

I don't see problems. I see a black background. You should learn how materials react on real world before .

The black part depends on the background. Your background is black (or dark), then you material can't reflect something else....

First of all you should ask to yourself:

What kind of material i need to obtain? What kind of metal?

Metal materials simply reflect the world around. You need to create something to reflect....

You have two ways:

1) model something around (... what can i say.. a simple interior?) ... but could be complicated.

2) use an HDRI images to simulate a real ambient (exterior or interior) with real reflections and lighting.

To start learning materials from scratch... second way is better

a) Create a Vraylight, set "DOME" as type.

b) find a free hdri image... for example from here (free samples)

https://www.hdri-hub.com/free-hdri-environments-for-download

c) put a VrayHDRI map on the material editor and use one of those image.. remeber to set mapping type to SPHERICAL.
Drag and drop that Vrayhdri to the dome Vraylight under "texture" on the main vraylight tab (where you see... "no map")

Refer to the vray manual to get more information.

then... you will be able to set up a generic material:

For example.. for a pure reflective metal.

1) Black diffuse

2) 255,255,255 reflection color

3) BRDF: Microfacet GTR ... better quality shader

4) Fresnel should be deactivated in most cases (your 16 value is not correct)

5) Glossiness depends on the material... you should use some referring image to understand better (let start with 0.98 - 0,95 - 0,85 and see what happens like images below)

This just to help you at least to start....

Have fun.

Marco

Alfred.DeFlaminis · ‎05-04-2017

Hello @Anonymous,

I am happy to help here, but I do think your problem is solved. You can see in the image named 201705042203.png that you are using only a half HDRI. The bottom half is black, as shown in the image below. This is the area that is reflecting in your first post. Either use a full spherical HDRI for reflections (or enable it on your light) or post a scene file so I can show you how. My guess is that your HDRI is half black and half an HDRI, it shows in your reflections. Since this is a Vray question this should be directed at Chaosgroup.

Best Regards,

Anonymous · ‎05-05-2017

sorry, i'm a beginner with the vray. but i use the hdr map on the light. i upload a scene file for you. i want to know why. maybe you can help me find the issues.

Alfred.DeFlaminis · ‎05-05-2017

Hello @Anonymous,

No need to apologize, I'm sorry if I made you feel that you needed to. I'm here for you to help in any way I can. I checked your scene and this entire issue comes down to simply a checkbox on the VrayLight. I have a screenshot below. Can you please try that for me? It really is better to address Vray questions to the good folks at Chaosgroup, but since neither of knew for sure that it was a Vray problem until I looked in the file I was happy to help here. I also stood the phone up and put the chrome on the whole thing and rendered... that black is now showing the brown from the HDRI. 🙂

Best Regards,

MarcoG67 · ‎05-08-2017

Hi,

I confirm that i don't see real problems on your file. i would suggest those little changes :

1) To avoid that "black line" on hdri reflections, alfred showed you on his last post, just click "Spherical (full dome)" under "dome light" tab (as Alfred showed you)

2) if you want to show your hdri as background (now is completely black) UNCHECK the flag "invisible" on options tab.

3) as i told you i think you could have better metal results using Microfacet GTR (GGX) shader without any fresnel that is not physically correct.

NOTE: condition (1) is indipendent from (2). Just try ckeck and uncheck invisible flag to see what happens.

... if you are using Vray3.50 i would suggest IPR (Interactive Rendering) to have real time changes of the scene during the setup.

Have fun!

Marco

Anonymous · ‎05-09-2017

@MarcoG67hello, i use the vray 3.4 for 3ds max 2017. the metal highlight on your picture is i wanted. can i ask you that how to erase the highlight of the vray retangle light? maybe i can try to change the angle of the hdri map to get the highlight. that picture is best of my rendering. can you give me a tutorial's detail about the metal shader. i used my way to try but it's hardly to control it.

Anonymous · ‎05-09-2017

so sorry, i'm too busy recently and my 3ds max can't run correctly. so i need to repaire it. but the problem still unsolved. and finally i'm reinstall the operation system. download the 3ds max againt and restalling it. forgive me that i can't response you quickly. you help me a lot. thank you so much. the model stand up is perfect reflecting. but lay it down still have lighting issues. i'm learning vray rendering from forum and youtube online. the chaogrup's forum is no one answer my question until now. maybe people use maya and mentalray or vray for maya be more.

Alfred.DeFlaminis · ‎05-09-2017

Hello @Anonymous,

Not to worry. I am here for you for any problem that I can help with. I think the original question was solved and you have some follow up questions which is totally fine. Just because a solution is found doesn't mean I abandon the thread though, so if you post in here I will get an email notification and I'll be here to reply. I'm not going anywhere.

Can I help with your Max repair issues? What is happening? What are the symptoms? (Happy to help.)

I am happy to help with Max issues and even general lighting questions, but please keep in mind that I can't do a lot of Vray Q&A because Autodesk doesn't make Vray. It does put me in a tough spot, though I do want to help. For each Vray light, you can choose what it contributes to. If you uncheck Affect Reflections, the reflection of the light won't be there, and so on and so forth. Please try that for me.

Best Regards,

Anonymous · ‎05-15-2017

it's been a long time. although the effect is not really good. but i want to share it to you. thanks for your help. can i ask you one more question? are you a designer? what's your job?

Alfred.DeFlaminis · ‎05-15-2017

Hello @Anonymous,

Happy to help.

Before this I was a TD, college instructor for 3D, a VFX artist, and a cg supe. I specialized in rendering and texturing. I'm also one of seven people in the US certified with Vray for 3ds Max. However, since Autodesk doesn't make Vray I don't feel right answering too many Vray things in the forums.

Best Regards,