Specularity maps in 2.8

Texturing with Bump, Specularity, and Displacement.blend (794.6 KB)

I’m trying to teach my students to use Bump, Specularity, and Displacement maps for realistic texturing in 2.8. I’m using the workflow from Andrew Price’s tutorial, https://www.youtube.com/watch?v=rzXNZkEoTAk

  1. I can’t figure out what I’m doing wring with the Specularity map. I have a hunch the problem is in the level adjustments I’m making in Photoshop. I can’t get rid of that awful white haze on top of the plane.
  2. Is this workflow obsolete in 2.8? If so, what is the best process for including bump, specularity, and displacement maps?

Thanks for any help you can offer me and my students.

Your file doesn’t have textures packed.

Before anything else-- I’m not an expert, but I’ll share what I’ve gathered from my reading. If people contradict me, you should listen to them.

Price isn’t doing stuff remotely realistically, or even traditionally. For one thing, he’s ignoring Fresnel. I’d suspect that’s what your haze is-- glossy reflections from someplace that shouldn’t really be reflecting because the surface is oriented toward the camera.

The traditional way to use a specular map is to use it to modulate specular-- ie, calculate specular, multiply it by your specular texture lookup, add that to your diffuse. This would be more akin to Price plugging a specular texture into the color input of the glossy node than using it as a mix factor.

But it’s not really designed for raytracers (although of course, you can create a texture to control any input you want.) If somebody wanted something that was specular mapped, I think the right place to demo that would be with Eevee, using a Specular node as your output. Again, the right place for the specular texture lookup is as an input into specular color.

Note that principled shader’s specular input doesn’t work the same. You can plug a texture into it, but not the same texture that you’d plug into a specular’s specular color. Principled’s specular is really just a remapped IOR for purposes of Fresnel.

Any real treatment of specular can’t be demonstrated with a flat plane, btw. It’s a bad test bed. You need variation in normals to really see what you’re doing.

spec has to do with light reflected from glossy surface by local light sources
so depends on how many light sources and angles between camera object’s faces and light sources location.

normally you don’t have to use such a map in a normal blender scene
unless you want to fake it with such a spec map !

happy bl

Texturing with Bump, Specularity, and Displacement.blend (1.8 MB)

The file should be packed. Thanks!

as bandages and RickyBlender sayed,the specular value, in the principled shader, are a simplyfied value of the IOR value the material has.

see this document that explanes the math.
https://docs.blender.org/manual/en/latest/render/shader_nodes/shader/principled.html

for glossyness you have to use the roughness input.how rough your glossy material should be (0-1)

and to make things clear about metallic input.this is used for masking. if you material is dielectric or a conductor.
input goes from (0-1).and 1 represent conductor mat /metal.this way cycles uses another math for better metal reflection.

and back to specular if you use a single material (plastic for example) then you dont need a map for the specular,because the whole material itself is made of plastic and has a IOR around 1.5 this is around 0.5 the basic specular value in the principled shader.

if you have the need for different IOR values,because maybe you have masked your material with two or more materials (mostly used then metal and a nonmetal material are masked)then you could feed the specular input for this aera with different specular/IOR values,if that makes sence.

hope this helps

edit,if you want to reduce the reflection even more or completly then set specular to 0

and the clearcoat you have only to use if you make a carpaint or similar that represent a glossy layer on top of your mat,otherwise at material creation first set the clear coat to 0.

Specular maps are kind of deprecated since PBR, except in a specular PBR workflow. It still has some artistic value. I use it frequently to simulate shadow gaps in flat geometry (0 specular with very dark color and high roughness); think floor boards with spacing between then, but done with a single flat plane. You should also lower the specular if you’re using builtin (buggy and feature lacking) or custom top coat, but maybe not to the point where you’d be using a map for it. In some cases, if normal/bump maps are costly to calculate, you may get away with applying a specular map and removing/reduce the bump calculation. Of course this won’t look like changed normals, but still improves the render.

Typically, you’d get a glowy edges phenomena if you use default fresnel to mix between diffuse and glossy for rough glossy, as in PBR the fresnel output also reacts to roughness. I can’t check your file right now.

or if you need,you can use moonys microroughness shader, to reduce the halo effect as workaround.

Words. I don’t have any words.

The math on the specular bsdf page, and the math on the principled bsdf don’t match, if you look at the examples.
The forumla and examples on the principled bsdf match, the formula and examples for the specular bsdf are not.
Or the math is wrong, or the examples are wrong. Both pages show the same example values, but different formulas. :wink:

oops you are right,i have corrected the link to principled shader

i am not sure, maybe these documents are not updated.afaik the math from the principled shader link is used.but the fresnel math from the specular is basicly the right fresnel math without the /0.08

and afaik the principled specular math is from the disney shader papers.

here the principled shader source code,see line 109
https://developer.blender.org/diffusion/B/browse/master/intern/cycles/kernel/shaders/node_principled_bsdf.osl

Hi Stan,

I really don’t appreciate this negative post. I’m here asking for help on how to create realistic looking textures in 2.8.

I’ve been teaching high school students age 14-18 how to use blender for 10 years. 3D modeling wasn’t invented when I went to art school, so I think I’ve been doing a really good job getting my students up to speed in the 40 minutes I see them each day for 180 days.

I’ve found Andrew Price’s cycles tutorial series to be the easiest, most effective way to let students learn by tutorial. The alternative is for the entire class to move click by click with me through the year. This is agonizing for advanced students who get it right away.

That being said, if you or anyone else here knows a good, free, and accessible resource for helping my students please offer that up, for I have spent countless hours on the internet looking for good resources and there just aren’t that many out there that go deeper than beginner level for texturing.

In my 3D Modeling course, I start students off with the Blender Basics classroom tutorial book by James Chronister. I think this resource provides a great overview of the Blender workflow. https://www.cdschools.org/cms/lib04/PA09000075/Centricity/Domain/81/BlenderBasics_4thEdition2011.pdf Chapter 4 covers textures, but it doesn’t get us to realism. We used to create the lighthouse scene in Blender Render. Since Mr. Chronister has no plans to update the book for 2.8, I’m looking for new resources.

Then I move into cycles shaders, using Price’s Donut tutorial series. But now that is also obsolete since the update to 2.8. Has has made a new series, but it doesn’t cover shaders as extensively as the series from around 2015.

After that, I ask students to create a food model scene of their choice. I’ve been pleased with the outcome of these artworks.

Next, we move into Hard Surface Modeling, again we follow a few tutorials on subsurf and mean creases to create a low poly car, then I ask students to do visual research to select and create a hard surface model of their own. Again, I’ve been very pleased with the results.

Later in the course, we move into low poly character modeling. I ask students to modify the tutorial example to make it their own.

We finish out the year with curves and NURBS.

I have a great program going. My students have been very successful. One of my students currently works for Pixar, since she transferred from Disney Animation Studios in Burbank, CA.

I think I have a good handle on modeling. The second level course is animation in blender. I’m good there as well.

WHAT I NEED HELP WITH: is realistic texturing in Cycles and Evee. I cannot find reliable resource that are easy to follow. Does anyone here know of a place I can find that? I’d prefer a tutorial series so that my students can follow along at their own pace, and I can facilitate, again, to eliminate the click by click problem.

I’ve been posting questions on this forum for about 9 years, and I have received countless valuable bits of knowledge that I have passed on to my students. Never have I encountered the unhelpful and rude feed back that you have posted here, Stan, This ain’t facebook. We’re here to help one another.
I was not expecting a troll here.

Thank you!

Thank You!

Thanks this does help.

Thanks You!

https://www.youtube.com/watch?v=IyUgHPs86XM
https://www.youtube.com/watch?v=j-A0mwsJRmk
You should have your students go through the above videos before even starting with shading and texturing in Blender. Not as a deep study, but to get some basic knowledge they can look back to if they need to.

here some good tutorials




there are plenty more,i think its a good start

Thanks, All. After watching through all of this, I’ve decided to start using the principled shader for most material setups. I’ve attached two screenshots for a wood table node setup. Does this look like I’m moving in the right direction?

For glass, should I use a glass shader or Principled? Same question for chrome.

Is there a lookup chart for common materials such as interior walls or should my students just “eyeball” the roughness settings?
Thanks.

Same, specular workflow is also harder to understand. I was tought on Max with the equivalent of blender internal and then a metallic/roughness workflow, but since both were so different I got super confused.
For me I would go with principled BSDF and metallic/roughness from the start.

the setup looks ok.for better result use a pbr setup and of course pbr materials/textures.which means to use seperate roughness normal or bumpmap and albedo for each material.this gives much better realistic results.

here a good pbr texture site

and about glass look at this

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