To get a better idea of what is going on, you may also want to change your honing direction between the 8k and the 16k, so that you can better see when the 8k scratches are gone. Make a crisscross pattern and stop when you can't see the 8k scratches anymore.
You will see more scratches per inch with a 16k than with an 8k because there is more grit per inch in the 16k than the 8k.
The 16k scratches should be narrower than the 8k scratches due to a smaller grit.
The 16k scratches should be shallower than the 8k scratches as well, but it is hard to judge the depth of cut in a picture.