Question about PBR textures

Hi guys. I’m currently learning about PBR textures, however, I am still confused many questions, I looked up online, there are too many various answers and they are not very clear. Here are my questions:
What does a Albedo map do? How do I use it in UE4?
If a Albedo map is about reflectivity, then doesnt it against a Reflectivity map?
What does a Microsurface map do? How do I use it in UE4?
What is a Mask map for? How do I use it in UE4?
And above all, Is there a way to create them in Photoshop software like Gimp? Because I don’t have the money to purchase 3DO,Ddo or Substance painter, so I’m looking for a alternative method to create them.

I know it’s a lot of questions, sorry, but I’m really just trying to figure this out, and learn to create and use them in the engine, please help me, thank you!


Albedo - is a clear color, exclude shadows, highlights, reflection and other.

Microsurface or Glossiness - is level of blurring reflection. In UE4 for blur reflection use Roughness, but data is opposite to Microsurface or Glossiness. For full reflect you need Microsurface or Glossiness set to 1, and Roughness - to 0.

Another features of UE4 shader is Metallic. It means, that you can use one shader for two shading model - Metall and Dielectric (wood, plastic, stown etc). 0 - Dielectric, 1 - Metall.

Apps like nDo, dDO, Substance can automatic extract all needed texture from photos. Or you can use Substance Painter for manually paint texture from scratch with real time preview in PBR mode.

You can read all about BPR in this links.

I got it. So basically I must use software like Ddo or Substance to achieve PBR result. Thank you!