Black lines on hair skull cap [Solved]

rames44

Iray render, using the Rochelle ponytail.  All of a sudden in a new render, this black stuff is showing up.  Same figure and hair I've used in plenty of other renders without this happening.  

I've tried removing and re-applying the hair, and also deleting and re-importing the figure I've been using into the scene.

Any idea what's causing this and how I fix it? 

EDIT: A friend told me that this is an issue of the skull cap incorrectly interacting with the figure's head, and that it can be solved by using adjustments on the hair.  In my case, I discovered that if I changed Hair > Actor > Adjust-CheekR and Adjust-ForeheadDepth to a few percent negative, the issue went away.  Only thing I don't understand is why it just suddenly showed up, but, well, I guess that's Iray... lol

mindsong

I believe there's a tweak with the smoothing modifier that can help with that too. Perhaps it's enabled on some items and not others?

--ms

rames44

Nothing like digging up an ancient thread, but this is frequently caused by having your figure well away from the (0,0) world point.  The infamous iRay bug...

FenixPhoenix

I suddenly started to have this issue as well. I didn't before, but it seems half the hairs I try end up with skull-cap problems. Tweaking the settings (depth to negative) does help, but I wonder what is causing it. Because hairs I never had problems with before, suddenly are showing this issue. OOT's hairs are especially bad with this and require quite a lot of tweaking now.

Anyone has any ideas?

ZippyGuitar

I've had this occassionally and the OOT hairs were the worst. Sometimes a couple of RedzStudio's hairs. Fixable in post work, but I would prefer not having to do it. While trying to find a fix, I changed the smoothing from Base Shape to Generic and it fixed my black line issues. Haven't had a problem since. Some of the newer hairs don't having a smoothing modifer and I still noticed the black jagged lines so what I did was apply a smoothing modifier and set the Smoothing Type to Generic, Smoothing Iterations to 1 and the Collision Iterations to 2. It all worked for me and I haven't noticed a problem since.

FenixPhoenix

GlenWebb said:

I've had this occassionally and the OOT hairs were the worst. Sometimes a couple of RedzStudio's hairs. Fixable in post work, but I would prefer not having to do it. While trying to find a fix, I changed the smoothing from Base Shape to Generic and it fixed my black line issues. Haven't had a problem since. Some of the newer hairs don't having a smoothing modifer and I still noticed the black jagged lines so what I did was apply a smoothing modifier and set the Smoothing Type to Generic, Smoothing Iterations to 1 and the Collision Iterations to 2. It all worked for me and I haven't noticed a problem since.

Thank you for the advice, Glen! Will use that when next I encounter the problem. Hopefully it'll work for me as well!

ZippyGuitar

FenixPhoenix said:

GlenWebb said:

I've had this occassionally and the OOT hairs were the worst. Sometimes a couple of RedzStudio's hairs. Fixable in post work, but I would prefer not having to do it. While trying to find a fix, I changed the smoothing from Base Shape to Generic and it fixed my black line issues. Haven't had a problem since. Some of the newer hairs don't having a smoothing modifer and I still noticed the black jagged lines so what I did was apply a smoothing modifier and set the Smoothing Type to Generic, Smoothing Iterations to 1 and the Collision Iterations to 2. It all worked for me and I haven't noticed a problem since.

Thank you for the advice, Glen! Will use that when next I encounter the problem. Hopefully it'll work for me as well!

I'm curious to see if this works for you and hope it does. I certainly haven't had an issue since trying this method.

FenixPhoenix

GlenWebb said:

FenixPhoenix said:

GlenWebb said:

I've had this occassionally and the OOT hairs were the worst. Sometimes a couple of RedzStudio's hairs. Fixable in post work, but I would prefer not having to do it. While trying to find a fix, I changed the smoothing from Base Shape to Generic and it fixed my black line issues. Haven't had a problem since. Some of the newer hairs don't having a smoothing modifer and I still noticed the black jagged lines so what I did was apply a smoothing modifier and set the Smoothing Type to Generic, Smoothing Iterations to 1 and the Collision Iterations to 2. It all worked for me and I haven't noticed a problem since.

Thank you for the advice, Glen! Will use that when next I encounter the problem. Hopefully it'll work for me as well!

 

I'm curious to see if this works for you and hope it does. I certainly haven't had an issue since trying this method.

I'd hope to test it out today, but I haven't finished some renders I need to do. I'll try to test it tomorrow and post my results here!

FenixPhoenix

GlenWebb said:

FenixPhoenix said:

GlenWebb said:

I've had this occassionally and the OOT hairs were the worst. Sometimes a couple of RedzStudio's hairs. Fixable in post work, but I would prefer not having to do it. While trying to find a fix, I changed the smoothing from Base Shape to Generic and it fixed my black line issues. Haven't had a problem since. Some of the newer hairs don't having a smoothing modifer and I still noticed the black jagged lines so what I did was apply a smoothing modifier and set the Smoothing Type to Generic, Smoothing Iterations to 1 and the Collision Iterations to 2. It all worked for me and I haven't noticed a problem since.

Thank you for the advice, Glen! Will use that when next I encounter the problem. Hopefully it'll work for me as well!

 

I'm curious to see if this works for you and hope it does. I certainly haven't had an issue since trying this method.

Ok, I had a recent problem with Sloane Hair where black lines showed when trying to apply it to a G8 figure.

As it happens, when I checked the smoothing modifier I realized it didn't have one! The solution was simply to add it! I'm going to start keeping an eye out for this. It's just strange because many of the hairs I had problems with, I didn't use to have said problems before!

 

But at the very least I'm happy that you've helped me find a solution! As much as I like doing post-work, some hairs were impossible. Like the OOT's corn braids (don't remember the name). I had a render using them and ended up changing the hair because it would require too much post-work to fix the showing skull cap.

ZippyGuitar

That's awesome! One thing I want to add, some hairs don't do so well with a smoothing modifier. I don't usually have issues, but when I do I dial the smoothing iterations down to 1 and collision iterations down to 2. I'm really glad that fixed your problem. I know how frustrating the issue can be.

FenixPhoenix

GlenWebb said:

That's awesome! One thing I want to add, some hairs don't do so well with a smoothing modifier. I don't usually have issues, but when I do I dial the smoothing iterations down to 1 and collision iterations down to 2. I'm really glad that fixed your problem. I know how frustrating the issue can be.

Yeah, I do believe the "corn braids" hair I tried to use before (I think it was OOT's, but I might've purchased it @ rendo) looked worse with the smoothing modifier (because in my desperation I tried to use that). Using the integrated morphs to pull the skull cap back also messed with how the braids met the head. I'll try revisiting the hair using your advice regarding smoothing iterations and collision. I think I didn't try adjusting collision at all, so there might be something there for sure!

henryqproductionsllc

I was using Caprice Hair for Genesis 8 and I had those damn black squiggly lines on my character's skull cap. With the Caprice Hair selected, I raised the Adjust Head size under SHAPING>ACTOR>ADJUSTING>Adjust-HeadSize. Problem solved.  =)

I added glowing eyes to the character also.

efron_24

what is a smoothing modifier

and where to find it

 

felis

Select the object in the scene tab, and click on the burger menu (the 3 horizontal line in the top left corner of the scene tab).

In there Edit > Geometry > Add smoothing modifier.

You can find the parameters in the parameters tab.

Richard Haseltine

felis said:

Select the object in the scene tab, and click on the burger menu (the 3 horizontal line in the top left corner of the scene tab).

In there Edit > Geometry > Add smoothing modifier.

You can find the parameters in the parameters tab.

Edit>Figure or Object>Geometry>Add Smoothing Modifier.

ChallyII

FWIW, I got around this issue by increasing the head size of the hair model by 10%

Darkend

ChallyII said:

FWIW, I got around this issue by increasing the head size of the hair model by 10%

I hate to keep bumping old threads, but I found that 2-3% on forehead depth adjust (most hairs include this) and possibly head width will usually do it. Failing that, scaling the hair works too.