It's complex but the stone you have is at the very limits of its usefulness on the steels you are sharpening. (the steel is almost as "hard" as the stone)
It's the reason for the different appearance and likely differing levels of sharpness your seeing.
thats odd i wouldn't expect 13c27 to be THAT hard, s30v maybe, it leaves a "bright" finish on my ats-34 but not mirror like the 13c27