Ok , I am going back quite a bit here so bear with me.

I got turned on to Pyro by Gordon Hutchings early 90's, at that time I had a small shop in Toronto printing for commercial photographers , before photoshop so there was big budgets and lots of film, I was using a lot of graded paper at the time and experimenting with split printing.

I do not believe everything I read or hear, so when people were boasting of the benifits of pyro I was curious.

so I did a lot of testing, and I mean a lot, included were some pretty good fine art photographers who were working only in BW.
We secured tons of films and did basically the one light source or high lighting range situation with different films and developers, we underexposed, normal exposed, overexposed with different times , under normal and push.
Then we made prints to 20 x24 to look at the results.

I followed Gordon Hutchings notes to a tee, and included this new to me developer into the mix.

In every case where strong lighting conditions were the source, myself and each photographer picked the pyro negs.. that were overexposed and drop developed as per Hutchings notes.
In every case the highlights were better defined and so too were the shadows.
This was with graded paper and all efforts were made to match the overall print.

Later came split printing which is not part of this thread, but it too opened more doors.

I think that each and everyone watching this thread should do this test, and see what their eyes are telling them, Pyro or Pyrocat vs Xtol or D76- same scene and pump up the lighting contrast.
Put the negatives and make prints, try to match and see which one works for you.

Michael I only can say that in every situation where there is strong lighting I recommend a staining/tannin/hardening developer with overexposure and under dev.
I am printing a show right now , 8x10 tri x in Pyro, indoor with window light only no flash and extreme long exposures to get the image.
I am absolutely certain that if we used D76 , the prints would not have the range that I am pulling out of them.
When you are at the extremes and trying to make a full tone print, there is a point of no return, blacks block up , highlights bloom and flare and go soft no matter how hard you try to burn in.

Remember the days of 7 to 8 stop burn ins on graded paper to bring in detail?
People resorting to hot water and finger development, muddy highlights.
Highlights not coming in no matter wtf you did.

When I brought Pyro into our workflow and split printing on VC paper those days are gone.
Probably dosen't answer you well but I am believing my eyes , rather than scientific proof or what is written, remember I did not immediately believe what Hutchings had to say.
Fred Picker wrote a lot about printing, I have all his notes, and books, his best advice was to test for yourself and see the results.

Quote Originally Posted by Michael R 1974 View Post
No no. I mean silver does not migrate. That's only one effect. There are still other things that enhance accutance and value discrimination in the tanned negative, like less halation and irradiation, and a lower probability of infectious development. I'm just suggesting people not go nuts thinking a stained negative will show massively different highlights than a well exposed/processed negative using a non-staining developer. I'd also add if exposure is heavy with Pyro/Cat, which several people on this thread have said they prefer, the enhancements pretty much go out the window. Sandy King has written alot about this stuff in other forums etc. For what it's worth I've done alot of my own experiments.

I'm curious though about your flared-out D76 comment. Why does it have to be so? I agree there can be *slightly* more "bloom" around such objects with a sulfite developer than a staining developer, but the value differences and detail can be just as good, albeit harder to print in some cases. Can you explain?