Very strange problem with ambient light in Poser 12. I have only found it in one particular product and have not been able to reproduce it in any other scene. With the Polygon City center product on 2nd world I noticed some strange behavior in SuperFly renders. After some research i isolated the problem to a single setting in a material.

With Ambient set to any value other than 0.

I have a nearly black render. All light rays are sucked in by the material.

When I set the ambient to 0 the render behaves as expected.

FYI I left only a single building visible in Raytracing and set all other parts to invisible and invisible in Raytracing. I did try this ambient setting on primitives and in other products and did NOT find the same problems. I'm not able to figure out what makes this situation unique. If anybody can recreate this problem with free products please tell us so we can try to get to the bottom of the problem. Thanks.

As if the ambient light was a negative one: kind of "eating" the outside lights.... Here is a test with 2 boxes, the left one with ambient, and in front of it a point light with a negative intensity:

if it only happens with this one model then it's probably normals.

Building on this idea I tried using a negative value for Ambient. To my great surprise the preview showed all black for the impacted areas but the rendering worked perfectly.

Tried this in Poser 11 and setting a negative value on ambient had the same effect on the preview but did not suck out all the light (the ambient simply didn't work).

Again trying this out on a primitive (positive and negative value for ambient) showed the same result for Poser 11 and Poser 12.

Conclusion: Under some unknown conditions a negative value for ambient shows as expected in preview (all black) but works perfectly in a render while a positive value also works as expected in preview (brightly lit) but works as a light suck in a render. Something is wrong here.

I'm not opposed to some material setting sucking in some light but having something sucking in all light regardless of the size and the value is a bit over the top. I did try this with a tiny value and it sucked in all light.

That IS weird. Do you have an envirosphere on that scene? Just curious.

Keeping it very simple. So no envirosphere, just a single infinite light, the problematic object, and a character (to show the effect). Works in Poser 11 and in Firefly (both 11 and 12).

What happens when you set your Diffuse-Value to zero?

Setting the Diffuse value to 0 doesn't make any difference.

I tried using different Firefly and Superfly materials and when setting the Emission value to any positive value the same problem occurred.

I've experienced this problem too. once when I loaded a scene from the library manager it had the same weird 'black light' behavior, but when i loaded the same scene as a save file it worked fine.

Just installed 12.0.289.

I had high hopes as it is supposed to fix "Emissive materials now render in SuperFly correctly. They no longer render invisible" but this particular problem isn't fixed.

Still hoping for a fix someday.

have you tried using cycles nodes only?