Why is there such visible banding on my greyscale gradient?

[lflegg]

I'm kinda baffled by this.

I'm working in 8 bit, so have ~16.8m colours at my disposal, right? Apparently beyond what's humanly perceivable.

Yet I see extremely visible (to the point of ugliness) banding on this simple black-to-white gradient:

https://i.imgur.com/jHsBEVM.png

what's with that?
As you can see, there's only one gradation between these 2 very visibly banding shades.

I tried playing with 16 bit but I don't know what I'm doing. Maybe my monitor is only displaying 8 bit anyway?

I literally just want a smooth gradient from black to white. Confused why this is so hard : /

[lflegg]

I guess each gradation is actually 3 gradations different, not 1. Because the red and green AND blue are all increasing by 1 each.

So I wonder if there's a way to make a multi-colour greyscale gradient that goes something like

R: 0
G: 0
B: 0

to

R: 0
G: 0
B: 1

to

R: 0
G: 1
B: 1

to

R: 1
G: 1
B: 1

to

R: 1
G: 1
B: 2

and so on?

[JJMack]

Is your image a grayscale image or an rgb image where all the images color are grays  where R=G=B=X  where X = a 8 bit or 16 bit value. 0 to F or 00 to FF Black to White

16Bit color depth gradients I believe you will find a smoother. 

[D Fosse]

You will get visible banding with 8 bit data. However, those bands will be regular intervals.

Enter your 8 bit display pipeline. This is where it can become ugly, with irregular banding and even color bands.

In short - work with 16 bit data, and you won't have any banding in the file. Any banding you see then, is in your display system.