Would be most grateful if someone could point me in the right direction regarding this matter, if you look at the attached picture you se that I get a very weird looking phenomena with GC enabled.

The only thing that differs in the render settings are GC.

Light = 1 point light

your shader is not set up to work with gamma correction...  there is some math involved..  I think (specular + Diffuse < 1)  when using GC & IDL.  

Shaders designed for older versions of poser dont look good with IDL and GC however if you look into snarlygribbly's scene fixer it can correct some of the cludges that were used in earlier version of poser that are no longer necessary and now produce undesireable results

Hi MeatSim and thank for your input!

The shader is not my work im afraid, its created by a vendor here at the marketplace.

I have snarlygribbly's scene fixer so i follwed your advice and tested various configurations but no luck.

Disabled Indirect light, but it still looks weird.

I do suspect the "gradient bump" and "gradient mode" nodes but dont understand enough of it to fix it.

I dont think an ambient value should be there either...  what does it look like with ambient value 0?

what does it look like with difuse 0.7 and specular 0.3?

reflection colour white?   

just spitballing.. I am so not qualified to troubleshoot anyones shaders!!

Quote - Hi!

Would be most grateful if someone could point me in the right direction regarding this matter, if you look at the attached picture you se that I get a very weird looking phenomena with GC enabled.

The only thing that differs in the render settings are GC.

Light = 1 point light

Strange, looking at the background alone shows the "With-GC" background being grey, while the "Without-GC" background being white. GC alone should never turn any grey into white, so there must be something wrong going on in your background shader.

For your material: Usually you do not GC normal maps, unless you created them that way (e.g. using some more esoteric software like gegl). At least that is the case for the usual image formats (png & such). I am not sure about PSD files but i guess they should not have GC neither. I.e. set the "Custom gamma value" in the image_map to 1, not to "use gamma value from render settings" and that should help with the plastic skin.

Would you be willing to give more information about that light, please?

Also, for the gradient_bump texture map, you want to have the Custom gamma value set to 1: this applies for all non-colour-information maps when using renderer GC.

That Gradient Bump Value should be 1.  Varying that value will not change the bump setting at all.

My background with gamma do look weird too now that you mention it :-)

I use Ambient oclusion on my render cube and my point light looks like this.

So the Gradient bump value is only on/off (0/1), thats good to now.

With PP2012, I would forget about ambient occlusion if rendered with IDL.  IDL essentially shuts down AO.  And AO is predominantly associated with Diffuse IBL.  Again, with earlier Poser versions, this workflow would be more appropriate, but IDL has changed this scenario significantly.

With IDL on you should not need or want AO at all...   IDL does what AO trys to fake.

Cant live without IDL anymore, better skip AO instead :-)

Thanks, you have helped me a lot!

When the materials are set up properly, GC should effect shadowing and highlighting only.

GC for transparency, bump, displacement and gradient bump should be 1, there is a Scripts menu option doing this.

Diffuse + Ambient should be less then 0.8, but the 50% grey establishes this.

Reflections > 0.1 are rare for non-metals, even diamonds don't reach 0.25. And specularity is a form of reflection, so count that one in as well. With this respect, the shader might be tuned a bit.

AO is meant for Diffuse IBL lights only.