I can't seem to get rid of these splotchy artifacts that are coming from the indirect lighting in the scene. The diffuse and SSS work fine on the actual(red) light in the scene, but the hall lights are light casting objects and indirect light are causing these. I bumped the indirect quality up to 100% and it did reduce it some but I can't get rid of it. It would be very difficult to re-create the hall lights effects with actual lights.

Try adding some low intensity point lights near where the splotches are happening. It might help to minimize their appearance. It's an old problem with Firefly IDL. You most commonly see it at intersections and corners of interior sets. It's not a problem in Superfly.

Though the splotches you're seeing might actually be something else... so there's that.

Check the texture maps for any mottle patterns, they may have been baked in.  In a scene like this, SSS will not play a significant factor, your figure is too far away to make a difference.  You will see the glowing effect only by ramping the scale on the node.  This might be an SSS artifact but it is hard to tell without seeing the texture first.

Is this a Firefly or Superfly render?  I am assuming Firefly because you mention indirect lighting.

It's a Firefly render... There are no splotches in the texture, but I am using SSS. I'm only seeing the artifacts on surfaces with SSS, it's some conflict with SSS and indirect lighting. I've used this skin shader in hundreds of renders and it hasn't been a problem before now.. But I usually avoid indirect lighting...

Which node are you using for SSS?

Here is my Shader setup for the face...

Seeing some unusual things going on. Uncheck reflection_light_mult. That's a  hack that's contributing nothing, probably to the shader's detriment, especially with GI.

It's also unusual that a bump, displacement, AND normal is going on. There's no math subtract modifying the displacement.

The shader looks like a scatter blinn setup, something that bagginsbill came up with and led to EZSkin.

Also looks a bit like it has both an image map mask AND a procedural mask modifying the specular. And both specular inputs are being used.

The scale value on the scatter is REALLY low, I'd be surprised if you weren't having blue tinting artifacts near areas of mesh in close proximity such as lips, nostrils etc. That's a very translucent setting.

Kind of a hodgepodge.

I'm far from a shader guru but even I can see some things wrong here... just from looking at various scatter blinn set ups and experimenting with them over the years. You might consider changing your set up to a straight EZSkin formula.

I leave it to folks more knowledgeable, just doesn't look like something I would use.

Here's a link to a pdf that explains what's going on in your shader set up. Some of it's outdated, it's pre introduction of scatter groups (which is a solution that's touch and go in itself, at least from my experience), but it's still useful if you're curious about the basics of scatter blinn...

http://www.penultimateharn.com/3dgallery/SubsurfaceScattering01.pdf

I would suggest to run that whole thing through EZSkin's Firefly shader setup, then render again. Refl_light_mult as stated above is an ancient hack from pre-Poser 8 days.

Also, would be good to know light setup and render settings.

With my more usual lighting setups I think my shader works pretty good? But always looking to improve it. I'm using bump, displacement, and normal for different things in the shader. Bump has the skin surface texture, Displacement has the veins, moles etc,... I don't normally use a normal map on my skin shader but was trying it here. It has evolved over time into what it is now and I'm sure there are some things that are now superfluous or unneccesary...  

I hate to break it to you, your scatter is not working.  You cannot connect a scatter node to an HVS node, they do not work together.  Notice the dashed connector wires between those two nodes, they're incompatible.  The Scatter node must be connected directly to Alt. Diffuse on the PoserSurface.  Your arrangement should look like this:

The Blinn is also broken, same lashed connector leading from it.  Your specular highlights are coming from the white chip above which is too bright for the setup in conjunction with the Alt. Specular.  You cannot use both the Blinn and specular nodes in the same channel.  The Blinn node is selfish, it also needs to be connected directly to the PoserSurface.  

The entire skin shaders really need to be reworked, there are major problems with the arrangement.  I could never run this in Superfly, the renders would be a disaster.  Believe me, I have done my share of problem-solving with this type of layout.

Great catch, my old eyes missed the dashed lines. I still suggest to run this through EZSkin, that will fix the dashed lines on all materials on figure automatically for Firefly.

I agree that running the entire shader through EZSkin will correct any existing problems.  However, the OP needs to understand why the connections are made and how they work, and the only way to learn this is to spend a little time in the material room and play with the nodes.  The screencap below is a very simplified node arrangement, I removed all the deadends and redundant nodes, essentially cleaning up the workspace.  This will work in Firefly with the right maps in place and a few more nodes but it will not flag errors in the log.

Judging by the images posted above I would say scatter is definitely active, too much actually but that a subjective thing. There's a lot of blue happening in the hands etc. And the SSS translucency is clear as day. If this is the same shader in use, as OP states, I think you may want to re-evaluate your diagnosis hborre. Additionally I believe that the dashed lines to connectors indicate Superfly incompatibility... as this is a Firefly render I'm pretty certain the presence of the dashed connectors is moot. Not trying to be contrarian here...

...

But yeah. Run it through EZSkin for Firefly. All in agreement.

Here's a scatter blinn that I use quite a bit in Firefly. I believe it works in Superfly but perhaps not optimally. Haven't tested it. It's not EZskin but basically the same thing... very similar to what hborre posted.

I disagree.  Node incompatibility can happen in both Firefly and Superfly according to the Poser manual, it's just that Firefly is more forgiving.  For the second set of images, I don't know what the lighting conditions are to make a complete assessment.  I do know that the specularity on the skin is very high, but that's my personal opinion.

...

It's all good hborre. I do mostly unrealistic toon stuff and morphing. Dial stuff. Rendering is a necessary evil lol. Just wanted to point it out. 

Didn't mean to step on toes.

Hborre, totally. If someone messes around making their own shaders, understanding node arrangements and functions beyond the novice level is needed. Thank you for taking the time to lay it out clearly.

Thanks for all the feedback! I realize There may be some weirdness in my shader setup, but primorge is correct in that the Scatter is definitely working.I'm not looking to redo my shader setup as I am pretty satisfied with how it normally renders in Firefly. I think my skin has decent depth and detail. I never render in Superfly because I've yet to see something rendered in it that didn't look either flat or grainy... I also don't use the Gamma correction in Firefly as I feel like it also flattens out the contours of the figure by washing out the shadows..... It just my preference. I am willing to look into what is and isn't working in my shader because of those Indirect lighting splotchy artifacts that I've been getting on my current renders...But, here is a very basic Scatter setup, still showing the splotchy artifacts......

Here's a more normal light set up with my shader...

I can't really add more than I have as I'm already knee deep in a personal project. I will note that the 2 identical texture maps into the blender running into hsv into scatter is nonsensical, at least to my eyes. Blenders are more resource heavy than a 1x1 multiply, in particular if they're not actually doing anything. So there's that. I would get rid of the additional image map and the blender, run the image map into the scatter color (and the preview diffuse at 0) and the scatter into the hsv to the alt diffuse... which seems to be a typical set up.

And get rid of the reflect_light_multiply (again). 

Have you tried the point light trick I mentioned earlier?

I take my leave.

Saying a shader is good because it works with some render settings is not entirely accurate. Different settings affect different things. But way deep in the archives of my memory where thoughts are unlabeled, coated in dust, and strewn every which way, I seem to recall that this issue might actually be caused by the irradiance caching. That might be too low or may need to be turned off altogether. However, if you turn it off, it may kill your render times.

IDL in Poser has always had problems.  For the most part it works for most people as they tend to do stills.  however, as RedPhantom says the issue is with the Irradiance caching.  

30 Second commercial by Richard60 (renderosity.com)

In the above video at about 15 seconds in look at the lower right corner of the image and you will see a black blob appears and disappear.  We edited the video to remove most of the blob by zooming in the area that was good (using our video editing software) and leaving out the bad part.   The blob is caused by the Irradiance cache making guesses as to what the lighting should be.  It uses a random number to determine how much and where to sample. The biggest problem is that each processing thread gets a different random number and sometimes you end up with a blob.  Only two ways to deal with it are 1:) render with a single thread and hope you get a random number that won't produce the blob, or 2:) turn off Irradiance caching this will lead to Poser examining each pixel which will take a very long time.

By changing the camera angle a tiny bit will produce another random number which might work well for what you are doing.

Thanks for the tips! I had a feeling it might be the irradiance caching.... Incidentally, If you look closely, you'll notice that the 2 diffuse maps are not the same. One has red lips, and one has natural lips. I was blending the two to have a slightly red lip....

Let's be scientific a bit if I may.

You say your shader works *under your very specifically set up lighting with render settings you have*.

You changed a variable i.e. the lights for a scene that is different.

The shader on your figure presented with those black blotches.

You asked why.

Very knowledgeable people offered suggestions here (I just dabble, not referring to myself). Very clear suggestions were made why your shader behaves the way it is, what specific nodes are not working or unnecessary, and suggested what you can try.

As was pointed out above, just because a construct works under one specific circumstance does not mean it is viable. As soon as you change one variable, it ceases to work--meaning you can only ever use it one specific way. That, for me, kills the joy of doing art (to go back from science to art a bit).

The way light reflects on a surface, the way changing that light changes that reflection, is, on our computers, becomes science again with the help of nodes, back from mystery--the more advanced the software we use becomes, the simpler it seems to be. Keeping up with those changes as Poser, in our case, is developed, is not easy and I still struggle with the way Superfly evolves and changes--in most of the cases, delightfully simplifying the way we do renders now.

I think it's a super valuable thing to have explained and dissected on these forums, and worth trying and working with.

Good luck with whatever you decide to you and thanks for all who shared their thoughts.

Richard60 posted at 10:15 AM Sat, 16 July 2022 - #4441372

IDL in Poser has always had problems.  For the most part it works for most people as they tend to do stills.  however, as RedPhantom says the issue is with the Irradiance caching.  

30 Second commercial by Richard60 (renderosity.com)

In the above video at about 15 seconds in look at the lower right corner of the image and you will see a black blob appears and disappear.  We edited the video to remove most of the blob by zooming in the area that was good (using our video editing software) and leaving out the bad part.   The blob is caused by the Irradiance cache making guesses as to what the lighting should be.  It uses a random number to determine how much and where to sample. The biggest problem is that each processing thread gets a different random number and sometimes you end up with a blob.  Only two ways to deal with it are 1:) render with a single thread and hope you get a random number that won't produce the blob, or 2:) turn off Irradiance caching this will lead to Poser examining each pixel which will take a very long time.

By changing the camera angle a tiny bit will produce another random number which might work well for what you are doing.

I haven't really run into a terrible amount of splotches with IDL. The occasional in room interiors which I fix with point lights or post. I use these settings quite a bit... obviously there's no one size fits all but I get IMO decent quality with this range. I mostly do OpenGL Preview stuff lately. Occasionally Superfly just to stay, from afar, in the loop...

I think I should clear up a few things... One, I do appreciate everyone who responded. You took the time to weigh in and try to help me out, so thank you! Second, my shader does not just work for me in one specific lighting or environment. It works like 90% of the time, which is why I was confused when I got these splotchy artifacts in the first place. I don't have, or know what 'EZskin' is. If you look at post 22 you'll see that I did try a simple Scatter setup based on suggestions but still got the same artifacts. I also tried to render just a small 1" square of the scene with Irradiance Caching turned off, but after 2 hours (as Richard60 predicted) I had to cancel it because it had not even finished the precalculations so I guess that isn't really a viable strategy... I just tried primorges suggestion of adding a low intensity point light (below render). It did minimize the splotchyness some but did not eliminate it, and also changes the scene lighting away from what I was originally after. It's somewhat disappointing because I was really liking the lighting in the hall before I added a figure. I used a half cylinder with the front half set as a light emitter around each of the hall lights, I don't know how I would achieve that same effect using real lights. I could probably simulate it with 3 spotlights apiece but that would add 24 lights to the scene....

If I were having the problem and really wanted to narrow down the culprit, I would eliminate the volumetrics and test and then eliminate the emitters and test. This changes the atmosphere and lighting but might reveal the culprit, if it's not the shader. This would just be curiosity.

I'll try and track down a link to an older version of EZSkin, but it might take a while. Prior commitments. Maybe someone else has a link handy?

At this point I don't think it's the shader. Seems like a lighting thing. And the irradiance cache route doesn't seem like a path you want to pursue...

EZSkin is a script based shader system by Snarlygribbly, free from his site (which I don't have to hand but someone will).  Download, install, run.  It's simple to use and once you have it, you'll be a lot happier.

Snarly's  scripts: https://cobrablade.net/snarlygribbly/poser.html

Will that script run in Poser 12? Python 3 unfortunately tanked a lot of good scripts....

There's versions of Snarlygribbly's scripts for P12 on the linked page.

Yes, the P12 version of EZSkin 3 is verifiedly works on P12 and is on that page.

why struggle with FF when SF will do ID light all day and night?

Yes that does look nice. But on the whole, so far people have looked terrible in Superfly.... Do you have any exaples with characters in it that look good? I did a quick render of my hall scene in SF, but even the stone walls looked bad. I would need to redesign all the materials for SF.

Forgive the nudity, Superfly render.

Hey thanks! That skin looks pretty good! It's a little dark to see it well, but I get that that's the mood you were going for. My problem with SF is the grainyness. Does that go away if you render longer? A lot of images I see rendered in SF are grainy like this..

Yes that does look nice. But on the whole, so far people have looked terrible in Superfly.... Do you have any exaples with characters in it that look good? I did a quick render of my hall scene in SF, but even the stone walls looked bad. I would need to redesign all the materials for SF.

Yes, It's a new workflow but after you figure it out all that stuff you want FF to do will happen without any pain.

shameless plug

https://www.renderosity.com/rr/mod/bcs/?uid=23947

In most cases, I trash the Firefly shaders and create a new Superfly shader from the ground up.  I've developed a workflow incorporating SSS in all my character renders, a system I created to optimize their skin textures.  The creature below is an example of that.

The following image is a reworked OBJ set freebie I picked up from ShareCG.  Everything has Superfly shaders that I created.  The dotted curtains, lampshades, and comforter are all procedural materials.

shameless plug

https://www.renderosity.com/rr/mod/bcs/?uid=23947

Here:

Sorry (or not...) but I couldn't resist to associate ghostship2's "shameless plug" with hborre's character somewhat... astonished
given the fact that  plug, well, look over at renderotica for the other, less official meaning... (or not)

@Y-Phil No b***t-plugs in my runtime. lol

I would say to use Bagginsbill's GenIBL to create an IBL map for your scene, and render in Firefly using IBL rather than IDL.  However, BB's downloads seem to have vanished into the aether... :sad:

Hmmmm... Does anyone else have it?

@Y-Phil No b***t-plugs in my runtime. lol