I want to go back to a previous post on old chemicals and chemical longevity.
Open a bottle of asipirin and sniff it. Leave it for a month or two and sniff it again. Keep doing this for about 6 months. It begins to smell like acetic acid and this smell increases over time.
Now, asipirin is one of the simplest of organic chemicals and most common. It goes bad gradually over several months to a year releasing salicylic acid and acetic acid. Ok, now consider the more complex chemicals used for photography. They go bad as well. We had expiration dates on everything and tested what we called "t" power which measured current activity of a batch of chemicals. The statements about old chemistry above by Ferrania just do not make sense in terms of real quality assurance.
I'm sorry to bring this up, but I think that fresh chemistry should be used, or re-purified chemistry should be used to assure that the first batch of film is acceptable. I'm sorry, but this is my first "negative" post here, but I felt obliged to bring it up after a bit of consideration. Consider the length of time from those post until now......
Sorry.
PE
I tried to make it clear that we are, in fact, producing new chemistry, but maybe I didn't give the full story here in this thread...
It's in the post:
Dead Link Removed - scroll down to the photo of the old bottle and read on.
I totally understand that what I posted is counterintuitive. Organic stuff decays. Entropy and all that. I accept this as fact - so thankfully, I don't need to sniff aspirin for the next six months.
But a bonafide genius, Marco Pagni, got quite excited and more animated than I've ever seen him when he described his somewhat recent discovery of the long-term stability of much of the chemistry we "inherited" from the old buildings. I'm pretty sure Ivano's arrival had something to do with these discoveries. The techniques used were unique to Ferrania, and supposedly one of the big reasons 3M bought them.
Also, way back in March of last year, we posted a piece about the purification process:
Dead Link Removed
Back then, we had little idea about the yield we would get once we started purification. As it turned out - most of the chemistry we tested is viable to a FAR greater degree than we knew when we wrote this post.
So yes,
if we use the old stuff, it must be purified. But for now, our small "kitchen" that you saw in the video about Ivano is perfectly adequate for us to begin production with all new chemistry.