[Solved] Dark Areas on Model - Clean Mesh and Normals - what have I missed?

I’m working on a model, and the mesh is plagued with dark spots as seen here.

First thought was reversed normals, and yes, the whole hand was reversed, did a recalculation and the normals flipped, but the problem persisted. Normals as seen are all pointed outward.

Second thought, Non-manifold mesh, Edge mode, selected non-manifold mesh, the only edges selected was the edge loop at the opening to the glove to the arm, nothing else.

Third thought, over sharp edges, applied an edge modifier, and changing the value in the modifier merely moved the dark spots around. Setting the mesh to Flat in both edit and object modes, pronounces the Tris, Setting Smooth, the dark areas persist.

Forth thought, Doubles or orphan verts, searched for loose geometry, nothing found. Did a remove doubles, 0 verts removed.

Have I missed some other setting to try or can someone think of a reason why this is happening?


Using Blender Render, Light is set to Hemi to light the entire scene for the pictures.

Never mind, found the problem, Normals Auto Smooth was turned on under the Objects tab of the Property panel on the object … (Doh!! the one thing I didn’t check!!)

(I believe this creates custom normals, I still don’t understand its function)

Not cancelling the post as it may help others.

Thanks Gang.

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Full interface screenshots, example .blend, and you would’ve saved yourself writing most of that, and wouldn’t be holding a guess-fest.

Doubt it. I think the problem is custom normals.

Thanks JA12, I was in the middle of posting the screen shot.

Auto smooth cuts shading above the set angle, unless custom normals override the angle. Turning it off doesn’t mean it was the source of the problem.

Can’t check that here since you didn’t post an example .blend. You haven’t posted a screenshot, it’s a cropshot, which I very much hate seeing in starting posts. It’s like asking what’s wrong with your car based on a picture of its logo.

There’s no objects tab of the property panel. What you refer to is object data properties in the properties editor, auto smooth option in the normals panel. They’re not tabs but context buttons, but no one calls them that.

Thanks JA12,
I appreciate your responses. I understand your level of frustration, as I too assist others. Please understand, I’m not trying to be snarky in this particular reply, I really do appreciate your responses, but keep in mind that a lot of us are mere hobbyists who are asking questions here and really don’t know what things are called officially in Blender but, in response to your last post…

First, I’m in the middle of the project and I’m not willing to release the .blend file at this point. I know that this is one of the things asked for when trouble shooting, I do it myself when helping others. But only when I can’t solved the problem after looking at picture provided by or that I request from the user needing help.

Second, because of all the various screens available in Blender, releasing a “Screen Shot” of the entire workspace is redundant as I may not have the panels required exposed. When I assist in troubleshooting, if I need to see a certain set of panels in a shot in order to help, in my response to the user asking for help, I ask for shots exposing panels “I” think are required. This cuts down on the number of shots (“cropped” or “full workspace”) being uploaded to the website.

As far as the “tabs/context buttons” are concerned (you, yourself, say no one calls them that), yes, I should have said the “Under the Object Data Context Button in the Normals panel, the Auto Smooth Checkbox was turned on” vice the “Normals under the Object Tab of the Properties Panel” if I wanted to be exact however, I think ppl (or people) would understand what I meant by looking at the cropped picture I posted.

Thank you for your explanation of the Auto Smooth check box. I still don’t understand the principals or the purpose of custom normals yet and at this point in modelling for me, it is not a concern. The fix I described cleared the issue for me on this particular model. However at some point of using this program, I will have to dig in and do some research on the topic, I’m sure.

Again, thanks for your responses, I hope that some will find them useful and assist them when requesting help here.

Smooth shading gets averaged based on the vertex normals of the model. When the face angle of the edges is too high, the shading looks bad, which can be fixed by cutting the shading on such edges.

Auto smooth uses split normals to do that without creating extra geometry. Edge split modifier splits the edges, so there are two unconnected vertices at the same location, again having two different normals. There’s also custom normals which comes either in the imported file, or you can change the normals yourself with various ways, controlling the shading.

Custom normals work with the auto smooth option enabled, overriding the angle. If there are custom normals, button to clear them is in object data properties -> geometry data: clear custom split normals data. That’s not there if there are unapplied modifiers in the stack that change the normals.

I do understand the reply, thanks for understanding mine and noticing it comes from frustration.

Common misconception. No one wants your work or whole project file. You can still prepare one for troubleshooting, and only include enough geometry to contain an example of it. The file will still include the cause of the problem when you make sure it’s still visible in it. In this case, few polygons would likely be enough.

Yes, could request a file, which would mean that at least half of my posts would be file requests, and some percentage of those would come back with “I can’t share the file”, which in turn would mean giving an extended description of what sharing an example file means, and why it’s important, and why bug reporting instructions tell to do that, why they should post one in the starting post.

I’ve already done a tutorial on that, and also requested similar instructions in the template here as they have on the bug tracker.

I don’t request files because it’s not my problem and I don’t need it, it’s much faster to close the tab. Requesting files on each that I might be interested in would be a huge waste of time. One moderator did that for years and has 3x more posts.

After answering around 10k Blender support questions here and elsewhere, and after writing a tutorial to help people work with the community instead of just talking at them, I think I’ve done enough. People are very creative with art and have attention to detail, but when it comes to communicating a problem, all of that gets usually forgotten.

Doesn’t matter if it’s a beginner user or an expert posting, they can be as clueless about posting, and the result is the same. With beginner questions there are many possible causes, and with experienced user posting, the answer won’t be obvious - either way, need an example .blend to not waste time guessing, and not to waste time starting something from scratch just to get visuals for posting.

When you include the whole interface, it tells which blender version you’re using, the render engine and viewport settings from the header which affect what you’re showing, and whatever else is left can be seen without you saying anything, which could hint to the direction of the cause. Hiding that information means redundant writing from you, and from others if they need to know by requesting that information you could’ve easily left in the shot and not write a word.

Someone just posted a good example Textures weird and fuzzy in material mode

Cropshots are ok when replying with answers, provided the cropping is done so that it provides context where to look, but not when asking for answers.

It’s still not a substitute for an example .blend, which will contain the cause of the problem. Or in case it’s a problem in Blender, it gets tested on multiple systems and the same file can be included in the bug report, just as the instructions say.

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