Last month Bloodborne's 1.04 patch added a new feature wherein players could play together regardless of their level so long as they used a password to connect to one another. This was a major boon for friends getting into From's latest at different times, as originally you could only play with those near the same level as you.
In the next version 1.05 update the guest's level will be adjusted to match that of the host if the difference is large, Sony noted on its Japanese PlayStation site. This should even things out a lot, so you don't have one player at level 20 doing negligible damage while their level 130 friend cuts through beasts like butter.
Furthermore, it will be made more apparent that a password is in use when initiating co-op via the Beckoning Bell or Small Resonant Bell.
The 1.05 patch should go live around 13th July after a maintenance update.
For now, enjoy this footage of Sony Worldwide Studios president Shuhei Yoshida kicking ass at Bloodborne.