Quote - I read about people working at extreme resolutions of 5000x5000 and up.

Is this more for printing purposes? Or do you get a better image using those resolutions... in the end when the picture is displayed it has to be reduced down to 1024x768 or 1280x1024 so dont you lose a lot of that detail?

 

It's to give you wiggle room to make corrections. You can painstakingly draw a human hair one pixel at a time or you can blow it up 5X and use the airbrush then reduce it back down. Charles Schultz used to draw Peanuts on huge newsprint sheets with a big square tipped marker. It lets you go fast and the reduction hides and smooths most of your errors.