D500 and ISO problems

[zombiesniper]

Fully agree with above.

High ISO isn't something to strive for but it also isn't something to be afraid of either.
In some situations it is the only answer.
Having said that if you have the light available to shoot at ISO 100 then there's usually no need to shoot any higher

 

[astroNikon]

more modern cameras with their High ISO gives the photographer greater flexibility.

I was at wonders when I used my d600 next to my d7000, which was much better than the d70.
And the d750 is even better than the d600.
Each camera is different. And the older the Nikon bodies the lower the ISO you want to use (in general). But these latest FF and DX are getting better and better with every iteration. It's all about learning how to use it for a proper exposure.