It's not 'unreal expectations' when I can do it on my D810. Which is my entire point. I *can* shoot 24/1.4 and get zero vignetting in post-processing.
Also I do shoot 35/1.4 (and 85/1.4) if you must know, but I, surprisingly, actually like to use different FOV for different shots. Imagine that!
You don't understand how HTP works - it does nothing to the Raw file when you shoot manual.
And you still don't get it - 5 stop pushes are fine and not 'bad technique' if you're doing it to save highlights. And totally possible with good sensors.
And ultimately, for sensors with little to no read noise, it's almost the same thing as shooting ISO 3200. So if you don't consider it unacceptable to shoot ISO 3200, then you can't say it's unreasonable to shoot ISO 100 & underexpose by 5 stops -- as long as you're doing it for a reason (say to protect highlights).
Unfortunately, I don't think you're going to be able to wrap your head around what I'm saying until you understand how these sensors/cameras work.
And if you must know - I shot multiple exposures & have one shot with 2 stops more exposure where the noise is acceptable in the subjects, but of course the sky is completely blown. My *point* is that I wouldn't have had to with a good sensor.
I get it that the D810 sensor is nifty.
But, why didn't you use a fill flash on that? It would have solved all of your problems, and you should probably have a flash on your camera at all times for outdoor portraits, especially weddings.
Were you just trying to rescue a bad error?
This is a legitimate question. Fill flash for outdoor portraits, pretty standard.