I think that all of you, dear professors, are not familiar with the concept of "Stress Test".
It's pretty simple, you test something in an exagerated way to see how far you can go before it breaks, think about helmet or crash tests for example, they push to the extreme to see how far they can go, to determinate the limit of an object. That's exactly what I've done, is strange that all of you, shining minds, can't catch it.
As I said already, vertical pattern noise is present all over the image in ANY LIGHT CONDITION at iso 1600, more visible in the shadows or underexposed images of course, still there at iso 800 on my camera, but less pronounced. I've just pushed to show it more clearly, seems obvious to me.
And this is not normal at all! Normal is noise at high iso, not a full grid of vertical lines, my test is to point out the problem, should be clear even for the luminaries of this forum.
Here's someone less professor and more smart!