For a long time now I have been using a textures on my characters ensuring the ScatterGroup is in different on adjacent materials.  I continued using the same figures after updating to 13.1.469 and the lines are back.

The fix for me is to make sure adjacent materials are now the same.  

I accept my skin texture is probably well out of date but I need some consistency for the story line I use the character for and do not want to update all my previous renders.  This present fix if fine for me but I did wonder about the change.

using "poser unimesh" under skinning method fixed that for me on most all V4 textures.

There was a change in Poser 12 that caused this with certain shader setups. Try changing the skinning method to unimesh.

You don't have to change the subdivision, just change the skinning method to Poser Unimesh, and the lines should vanish.

Changing to Unimesh did not work for me, I tried in the hope that it would, it was only when I changed the ScatterGroup did they disappear.  It only seems to have happened since I updated to 13.1.469 before then all was well. It is not a major issue for me, I just wondered if anything had changed.

Could this be the reason?

Poser 13: A World of Possibilities - Poser - 3D Rendering & Animation Software (posersoftware.com)
Quote:
"Poser 13 is almost here, and we're excited to share with you some of the new features and improvements that will be included in this latest release. Unfortunately, end-to-end support for unimesh figures will not be included in the initial Poser 13 release. We understand that this is not ideal for content creators looking to seamlessly interchange data with other 3D design tools. To help with this, we have been working to improve Poser's design tools to simplify tasks such as creating clothing for figures. Fortunately, end-users creating scenes, rendering images and producing animations will not be affected and will find plenty of cool new features in this release."

Nevertrumper posted at 12:51 AM Tue, 10 October 2023 - #4476063

Could this be the reason?

Poser 13: A World of Possibilities - Poser - 3D Rendering & Animation Software (posersoftware.com)
Quote:
"Poser 13 is almost here, and we're excited to share with you some of the new features and improvements that will be included in this latest release. Unfortunately, end-to-end support for unimesh figures will not be included in the initial Poser 13 release. We understand that this is not ideal for content creators looking to seamlessly interchange data with other 3D design tools. To help with this, we have been working to improve Poser's design tools to simplify tasks such as creating clothing for figures. Fortunately, end-users creating scenes, rendering images and producing animations will not be affected and will find plenty of cool new features in this release."

Cloud be, it certainly shows some work was done in that area.

I think that is a texture image filtering effect

If you share the file, maybe we can test and figure out a solution together... or at the very least submit more bug reports if it's a bug that has copped up in the latest build.

CobraBlade posted at 11:19 PM Sun, 15 October 2023 - #4476327

If you share the file, maybe we can test and figure out a solution together... or at the very least submit more bug reports if it's a bug that has copped up in the latest build.

That could be difficult as it is a custom character incorporating a lot of commercial content such as the image maps.  I am not sure it is worth sure it worth raising a bug report as this thread suggests I may be the only one seeing or being bothered by it.

I don't know it that's the case or not for your character, but I've seen that effect, from time to time, when some parts of the topology were too near, for example between the breasts when they're too near, but: it appeared only once, on one character.
It that concerns different parts of the body, you may try different scatter group IDs,

Y-Phil posted at 4:06 PM Mon, 16 October 2023 - #4476360

I don't know it that's the case or not for your character, but I've seen that effect, from time to time, when some parts of the topology were too near, for example between the breasts when they're too near, but: it appeared only once, on one character.
It that concerns different parts of the body, you may try different scatter group IDs,

The whole issue started way back when Sub Surface Scattering was first introduced and the lines were noticed on adjacent groups such as arm and hands or shoulder and body and the recognised solution was to make sure adjacent group were in different scatter groups.   As I have been using my character for sometime, to tell stories, my character follows that convention and has not shown the lines for a long period of time, at least up until the latest issue of Poser 13 when they reappeared.  I tried using Unimesh as a skinning method but the lines remained then, in sort of poke and hope testing technique, I changed all the scatter groups to the same group and the line disappeared.

As I have a solution it is not really and issue for me and all I have to remember is to do the change if I return to an older scene to do an update.  The reason I started the Thread was two fold, first to highlight the problem in case anyone was seeing the issue and had not found the fix and secondly, as a matter of interest, to see if anyone knew why the issue had re-appeared in the latest release.  As I have a simple solution and no one seems to have the same issue I really don't see it worth making an bug report, particularly when I have a suspicion, based on my years spent as a field trial manager testing software releases, that the whole situation may well appear in a future release.  

hornet3d posted at 12:10 AM Tue, 17 October 2023 - #4476378

Y-Phil posted at 4:06 PM Mon, 16 October 2023 - #4476360

I don't know it that's the case or not for your character, but I've seen that effect, from time to time, when some parts of the topology were too near, for example between the breasts when they're too near, but: it appeared only once, on one character.
It that concerns different parts of the body, you may try different scatter group IDs,

The whole issue started way back when Sub Surface Scattering was first introduced and the lines were noticed on adjacent groups such as arm and hands or shoulder and body and the recognised solution was to make sure adjacent group were in different scatter groups.   As I have been using my character for sometime, to tell stories, my character follows that convention and has not shown the lines for a long period of time, at least up until the latest issue of Poser 13 when they reappeared.  I tried using Unimesh as a skinning method but the lines remained then, in sort of poke and hope testing technique, I changed all the scatter groups to the same group and the line disappeared.

As I have a solution it is not really and issue for me and all I have to remember is to do the change if I return to an older scene to do an update.  The reason I started the Thread was two fold, first to highlight the problem in case anyone was seeing the issue and had not found the fix and secondly, as a matter of interest, to see if anyone knew why the issue had re-appeared in the latest release.  As I have a simple solution and no one seems to have the same issue I really don't see it worth making an bug report, particularly when I have a suspicion, based on my years spent as a field trial manager testing software releases, that the whole situation may well appear in a future release.  

Now that you're saying that, I've remarked some subtle differences in my way of using the PrincipledBSD node, in particular the Legacy Scatter checkmark and the SSS Method parameter, but as I haven't run any specific test, I can't be sure if it's related or not.

Y-Phil posted at 1:18 AM Tue, 17 October 2023 - #4476379

hornet3d posted at 12:10 AM Tue, 17 October 2023 - #4476378

Y-Phil posted at 4:06 PM Mon, 16 October 2023 - #4476360

I don't know it that's the case or not for your character, but I've seen that effect, from time to time, when some parts of the topology were too near, for example between the breasts when they're too near, but: it appeared only once, on one character.
It that concerns different parts of the body, you may try different scatter group IDs,

The whole issue started way back when Sub Surface Scattering was first introduced and the lines were noticed on adjacent groups such as arm and hands or shoulder and body and the recognised solution was to make sure adjacent group were in different scatter groups.   As I have been using my character for sometime, to tell stories, my character follows that convention and has not shown the lines for a long period of time, at least up until the latest issue of Poser 13 when they reappeared.  I tried using Unimesh as a skinning method but the lines remained then, in sort of poke and hope testing technique, I changed all the scatter groups to the same group and the line disappeared.

As I have a solution it is not really and issue for me and all I have to remember is to do the change if I return to an older scene to do an update.  The reason I started the Thread was two fold, first to highlight the problem in case anyone was seeing the issue and had not found the fix and secondly, as a matter of interest, to see if anyone knew why the issue had re-appeared in the latest release.  As I have a simple solution and no one seems to have the same issue I really don't see it worth making an bug report, particularly when I have a suspicion, based on my years spent as a field trial manager testing software releases, that the whole situation may well appear in a future release.  

Now that you're saying that, I've remarked some subtle differences in my way of using the PrincipledBSD node, in particular the Legacy Scatter checkmark and the SSS Method parameter, but as I haven't run any specific test, I can't be sure if it's related or not.

That is part of the point really, changes could be made that work quite happily if you are building a figure/scene from scratch but there may be an issue when using figures that have an existing SSS setup from an early version of Poser.  That is the cost of change and progress I suppose but for story tellers that want consistency throughout a story the need to be able to use  existing figures is important.  It is one of the reasons I do not immediately jump to a new figure when it is released as i have to go back and recreate existing scenes with the new figure.

How simplified could you get the scene while still getting this issue? Perhaps you could save a new scene, and take out anything unneeded to replicate this.

CobraBlade posted at 8:53 PM Tue, 17 October 2023 - #4476435

How simplified could you get the scene while still getting this issue? Perhaps you could save a new scene, and take out anything unneeded to replicate this.

I could make the scene very simple by just having the figure in the scene and it is very easy to duplicate the problem, all I need to do is change the scatter group on any part of the figure to be different to an adjacent body part.  The issue is that the figure I am using is a customised version of Dawn SE created by a using morphs from a couple of commercial morph packs and commercial Image packs.  This being the case I cannot see how I can share the figure for someone else to do the testing.  

What I have done is used the base Dawn SE with the basic SSS skin and there are no signs of any blue lines which points to my skin setup for my character.  On the other other hand I have not changed the character in any way and the lines do not appear on any render in the previous version of Poser 13 but they do on every render using the latest version.  That said, it is an easy fix and I do not need to go back to the earlier renders and update them.

Due to it only being a recent issue, it could all come down to needing to file a bug report.
Even so, if you use your skin on the standard Dawn SE, do you still get the blue seams? If so, could just save that and share the scene.