This is a repair job we did. There had been a leak  from an upstairs shower that damaged the ceiling in the
living room. While we were there the homeowner decided to fix some other problems from previous bad
hanging and finishing.
The long bands are because the ceilings are nine foot and instead of using 54" drywall they cut a one foot
rip, and then the finishers didn't float out the joints properly.
There were also several places in the ceiling that apparently never got sanded. So we skimmed over them to
hide them.
Here is a before and after. This ceiling was only nailed, no screws, they also left big gaps in the angles. The
finishers just taped the angles instead of packing them with setting type joint compound to prevent the
cracking you see. We ripped all the old tape off, packed the cracks properly, and retaped.
On the left is a crack under a window, which we screwed off properly, and retaped. On the right is where the
patch was the plumbers cut out to fix the leak.