Sorry I'm late to the party. I'm wondering if you misread the sheet in the box, or got the wrong sheet?
Going back to old Kodak data sheets, and to the HC110 Resource Page, that 7.5 minutes time was Kodak's
recommendation for old Tri-X TX ISO
400, not TXP ISO 320.
The questions, as I understand them, are:
1. Has Kodak Tri-X Pan Professional ISO 320 film changed since 1988?
2. Has Kodak HC110 developer been reformulated since 1988?
3. What is the correct development time for 1988-vintage Tri-X Pan Professional ISO 320
film in 2019-vintage HC110 developer (dilution B at 68F/20C)?
The answers, based on quick research on-line and in two books, appear to be:
1. Definitely. And development times for Tri-X decreased.
2. Maybe. But if so, times for HC110 did not change much, if at all.
3. The HC110 Developer Page (not affiliated with Kodak) recommends
for (old) Tri-X Pan Professional ISO 320 in HC110 dilution B
(method and agitation unknown) 5.5 min @68F/20C.
(assuming HC110 has not been reformulated between 2012 and now.)
In 2002 Kodak changed the composition of a number of films to reduce the silver content.
As a result, "Tri-X is now a semi-flat-grain film with color-dye sensitizers" (Steve Anchell,
Darkroom Cookbook, Third Editon, p . 36). The new films have slightly altered
designations and development times for all the films decreased.
The following table is compiled from the HC110 Developer Resource Page
http://www.covingtoninnovations.com/hc110/Development times for Kodak Tri-X Films in HC110 (c. 2012) dilution B:
OLD FILM (before 2002) NEW FILM (2002 and after)
Tri-X Pan (TX) 400 7.5 min* Tri-X Pan (400TX) 400 3.7 min **
Tri-X Pan (TX) 1600 16 min data missing---film no longer made?
Tri-X Pan Prof (TXP) 320 5.5 min Tri-X Pan (320TXP) 320 data missing
* -- author states that this time (ISO 400) was "a bit long" and recommends 6-7 minutes.
**--author states and (and I concur) that 3.7 min is too short to be accurately stopped.
He thinks it's an error, but I think they just didn't want to add a new dilution.
Anyway, he recormmends having the strength of dilution B and developing for
6.5 min. It's academic, since this is for the new film, not the one you have.
The other consideration is the developer. HC110 has definitely been reformulated
at least twice. According to the above page, " The syrup is lighter-colored than it
used to be; for a while, in the 1980s, it was quite yellow." According to
The
Film Developing Cookbook by Stephen G. Anchell and Bill Troop, HC110
contained pyrocatechin for at least one year. That book contains a formula for an
HC110 prototype taken from a Kodak's US Patent #3,522,969 (not 3,522,060 as
given in the book).
With very old film, you can expect a bit more fog. Fortunately, HC110 is very good
at restraining fog. It might be a good idea to pre-soak to soften the old emulsion.
More info on developing old film:
https://www.lomography.com/magazine/169603-expired-film-developing-ancient-black-and-white-filmSorry I can't be more definite, but it sounds like you've made some progress.
Sorry I'm late to the party. I'm wondering if y... (