"ok, some of what you're saying just isn't making sense to me.  5% ambient light should, i would think, mean that if it's lit by nothing else, it should be at 5% lumniance, right?.  and all the way up to 100.  nothing should make 5% ambient light translate to say 20 or 50 % luminance, right?"

Ok, you wrote a lot but its all predicated on this premise. So let's just deal with this one tiny point.

Nobody said 5% ambient light should translate to 5% luminance. It should produce 5% luminance.

Now, on a voltage scale of 0 to 1 volt (1 volt being 100% brightness), how many volts should you send to the monitor, in order to produce a 5% luminance?

Is the answer .05 volts? No it is not.

We've already seen from the GC test image I posted that .68 volts STILL isn't even to produce 50% luminance on your monitor (splat #5).

So how many volts are necessary to produce 5% luminance?

BoP = V ** 2.2

In this case, BoP (brightness of pixel, or luminance as you called it) is supposed to be 5% or .05, right?

.05 = V ** 2.2

.05 ** (1 / 2.2) = V

So the voltage necessary to produce a 5% luminance on your screen is .05 to the power 1/2.2. The resulting voltage is about .256, or roughly 25.6% of the maximum voltage.

So in order to get a 5% luminance, you must send a 25.6% voltage to the screen. What is the RGB value? WIth 8-bit RGB, the maximum is 255, so 25.6% of that gives us RGB(66, 66, 66).

So - when you put RGB(66, 66, 66) onto your screen, it is only visually 5% as bright as RGB(255, 255, 255) on your screen.

Once you grasp the significance of this, you will see why the VSS shader is sending such huge numbers to the screen - that is what gamma correction is.

The other point I'm trying to make is you have trained yourself, through years of dealing with renders, into believing that 5% luminance is RGB(13, 13, 13), which it decidedly is not. That is a 5% voltage, to be sure, sent to your monitor, but it produces a 1.3% luminance. To get a 5% luminance, you must send a 25.6% voltage. As a result, you have also trained yourself to believe that 5% luminance is very very dark, and should barely be perceptible. In reality, it is easily bright enough for you to see things clearly.

You are used to Poser renders, produced in linear space, and viewed on your computer monitor severely darkened. You have accepted it, and now reject the "glowing" ridiculous visibility of a GC'd render.

I have never accepted the dark images, and have worked for two years to find ways to correct what I knew all along did not look like real ambient light. I thought it was Poser's lighting model. It is not Poser's lighting model. It is that we've failed to do what is necessary to encode the final render for the device we intend to see it on.

As I've said before, if you treat your scene as always, you will be disappointed by GC. You will screw up your colors and brightness and lose your dark shadows. But this is not the fault of GC. It is because you've just got too much light in your scene, and you never saw it for what it really was. Once the true amount of light is revealed, it is obviously necessary to start using less light.

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Renderosity forum reply notifications are wonky. If I read a follow-up in a thread, but I don't myself reply, then notifications no longer happen AT ALL on that thread. So if I seem to be ignoring a question, that's why. (Updated September 23, 2019)