Positive opk

I have had two days of very strong positives and today they are dark but definitely fading (I have a fade in fade out affect with OPKs) my question is I know we typically ovulate 12-36 hours after so if my test has faded today does that mean I ovulated yesterday or am ovulating today? Does an Opk catch the surge right up until ovulation or do we continue to surge even while ovulating? My temp only went down by .23 last night so I wasn’t sure if that could signify an ovulation dip.

Thanks for the help :)