exporting into obj

1. You need to export a Standard material, not Vray materials.

2. With standard materials you are still limited by the maps you can use in your material. The ones that you cannot export are: Specular Level, Glossiness, Filter Color, Refraction & Displacement. The other texture slots work for obj.

reflection map works with standard materials.

No way to export vray materials to obj.

you can get converters online that convert vray materials to standard materials with varied success (complex materails wont easily convert to standard). PBR is fairly straight forward.

For all my models I always make both standard and vray materials so that they can be used without any render plugins.

A quick correction to the above information - *.obj does support specular information.

Here is a quick description of the *.obj file format specifications. Scroll far down the page to see the possible "material" specifications that can be used for an *.obj file. (https://en.wikipedia.org/wiki/Wavefront_.obj_file).

Answer to the last question is "Yes." I sell models in a lot of different file formats. Many people want to purchase only the *.obj version because they are going to use an independent renderer, such as Maxwell Render. These customers will use the shaders and materials most appropriate for their particular rendering engine. Given the large number of customers like this, it is important to give a good name each material you apply to the different parts of your model that will go into *.obj file format,... so that the customer will be able to figure out the best shader for each part. For example, you may apply just a grey lambert material to the parts that are glass, but you should clearly label the material for that part to be something like "dark green glass". Your customer will be able to quickly apply the most appropriate shaders in his or her rendering engine to your model, and be grateful to you.

FYI obj does support Specular Color, not Specular Level. You can test it yourself otherwise.

You are correct.....

It is very interesting...

obj not support specular map

I'm not sure this is correct. I usually include simple specular maps with my models in *.obj file format, and the *.mtl file does reference them.

By the way, I really like your models, PBRCool!