der-photofreund wrote
: Hi Mirko,
Thanks for your comments. Are you out and about late at night as well, or . . .?
No, we’re currently travelling with a 9-hour time difference ;-)
As far as shelf life is concerned, you have to distinguish between powder chemistry and liquid chemistry in exactly the same way.
With both, there are good and bad examples. The active substances oxidise or tend to react in other ways if you don’t prevent them from doing so.
As you rightly observed, we vacuum-seal them lightly and use high-quality bags. We even make these by hand, as we haven’t found anything better off the shelf so far.
On top of that, we do a bit of secret voodoo to keep our powder chemistry stable, so that we can confidently guarantee the two-year shelf life. Of course, that doesn’t mean it won’t last longer.
XT-3 is Xtol, and this developer has never been known for having an indefinite shelf life. It is a fantastic developer: with fine grain and sharpness, it brings out the speed, and it is the most environmentally friendly film developer of all, apart from recipes that cannot be reliably produced on an industrial scale.
XT-3 has exactly the same shelf life as Xtol always has had. The discolouration of the powder is intentional on our part and, so to speak, an indicator of the famous ‘sudden death’ that older Xtol can exhibit. Once Part 1 has discoloured, XT-3 should no longer be used.
When it came to stockpiling, ATOMAL was the first choice. However, due to the borate ban (or more precisely, the current borate limit), we have run into difficulties there too. The result is a three-part packaging, and here too the recommendation is to use it within two years.
Incidentally, this guarantee applies to all manufacturers. They just state it more or less clearly.
What we could do is produce a D-76 with borate within the (still) permitted limits and in a two-part pack. That should last longer.
That would then be, so to speak, a product designed solely for this one application (stockpiling).
I can’t say whether it would be worth it. The two-part packaging would make it more expensive, it would be less environmentally friendly, and the only advantage would be a shelf life of certainly >2 years. What do the others think?
Would you want something like that, and would you be willing to pay more for it?
Of course, all this applies only to developers. All other powder chemicals have a much longer shelf life than the liquid concentrates.
We are constantly improving our products. We have already made progress in the shelf life of the powder developers.
Current batches should already be better than the first ones.
And honestly – even with children – two years is quite a long time ;-)
Two Christmases, several birthdays, two Easter holidays, two Father’s Days, two Germany Days… you’ll easily manage to fill the film :-
Best regards,
Mirko
