Originally Posted by mascior
My display exhibits the same behavior. With the eeColor box on, 18 and up flash. However, on bypass I can get 17 and up to flash. A Pure power gamma 2.22 I set black offset to 98% and can get 17 to flash. However, with bt.1886 17 flashes?!?
It's hard off hand to know if the first step above black should be visible or not, since it depends on a lot of factors. A power curve is extremely shallow near zero, and there is no surprise if a pure power curve is being used, that the first step is invisible. For an input offset (BT.1886) style curve, it depends on the power and what the offset is. If the black point is quite dark, then again the step might be too small to see, even if it is being displayed correctly.
For instance, let's say you have a black of 0 and a white of 200 cd/m^2 and a gamma of 2.3.
The first step is (1/220)^2.3 * 200 = 0.000004 cd/m^2.
I suspect you would have trouble distinguishing that step, or even several above it, even
if it was displayed accurately.
Let's look at an input offset/BT.1886 case: Black 0.02 cd/m^2, white 200 cd/m^2, gamma 2.4.
Input offset to match the black will be 0.022018
The first step will be ((1/220 + 0.022018)/1.022018)^2.4 * 200 = 0.03138, a step of about 0.01 cd/m^2.
I guess this may be visible under good circumstances, but it's hard to be sure - having patches > 10 cd/m^2 in your view may make this impossible - i.e. this step may only be visible if you just display the first few steps in isolation on an otherwise black screen. Against full white, its's a ratio of 0.01/200 = 20000:1, which may be beyond human capability - internal glare in our eyes limits our static contrast range to about 1000:1.
With manual control and a sharp enough transition to adjust, then you can force 17 to flash - but being visible doesn't make it correct.