I was reading about Jean-Loup Sieff's bio, and it appears that he used tri-x developed in d76.

At some point (1975) Kodak changed the formula of d76 so he and a bunch of other photographers had to start making their own developers, according to the old d76's formula.

Then a friend pointed out to me that tri-x has also changed somewhere in 2004.

my (many) questions:

- how different is the new tri-x from the old one: maybe it just does more but the overall look of the pictures os the same, or not?
- can hp5 emulate the old one or maybe a rollei or maybe something else?
- how really different is the old d76 from the new one (this one is for old timers really) ?
- and even re-making the old d76, will it have the same effect on either new tri-x, or the equivalent of the old one...